DDoS detection Let s assume we want to detect DDoS targeting our customers. As an example, we consider a DDoS attack as a collection of flows over one minute targeting a single customer IP address, from a single source port and matching one of these conditions:

• an average bandwidth of 1 Gbps,
• an average bandwidth of 200 Mbps when the protocol is UDP,
• more than 20 source IP addresses and an average bandwidth of 100 Mbps, or
• more than 10 source countries and an average bandwidth of 100 Mbps.

Here is the SQL query to detect such attacks over the last 5 minutes:

SELECT *
FROM (
  SELECT
    toStartOfMinute(TimeReceived) AS TimeReceived,
    DstAddr,
    SrcPort,
    dictGetOrDefault('protocols', 'name', Proto, '???') AS Proto,
    SUM(((((Bytes * SamplingRate) * 8) / 1000) / 1000) / 1000) / 60 AS Gbps,
    uniq(SrcAddr) AS sources,
    uniq(SrcCountry) AS countries
  FROM flows
  WHERE TimeReceived > now() - INTERVAL 5 MINUTE
    AND DstNetRole = 'customers'
  GROUP BY
    TimeReceived,
    DstAddr,
    SrcPort,
    Proto
)
WHERE (Gbps > 1)
   OR ((Proto = 'UDP') AND (Gbps > 0.2)) 
   OR ((sources > 20) AND (Gbps > 0.1)) 
   OR ((countries > 10) AND (Gbps > 0.1))
ORDER BY
  TimeReceived DESC,
  Gbps DESC

Here is an example output¹ where two of our users are under attack. One from what looks like an NTP amplification attack, the other from a DNS amplification attack:

TimeReceived	DstAddr	SrcPort	Proto	Gbps	sources	countries
2023-02-26 17:44:00	::ffff:203.0.113.206	123	UDP	0.102	109	13
2023-02-26 17:43:00	::ffff:203.0.113.206	123	UDP	0.130	133	17
2023-02-26 17:43:00	::ffff:203.0.113.68	53	UDP	0.129	364	63
2023-02-26 17:43:00	::ffff:203.0.113.206	123	UDP	0.113	129	21
2023-02-26 17:42:00	::ffff:203.0.113.206	123	UDP	0.139	50	14
2023-02-26 17:42:00	::ffff:203.0.113.206	123	UDP	0.105	42	14
2023-02-26 17:40:00	::ffff:203.0.113.68	53	UDP	0.121	340	65

DDoS remediation Once detected, there are at least two ways to stop the attack at the network level:

• blackhole the traffic to the targeted user (RTBH), or
• selectively drop packets matching the attack patterns (Flowspec).

Traffic blackhole The easiest method is to sacrifice the attacked user. While this helps the attacker, this protects your network. It is a method supported by all routers. You can also offload this protection to many transit providers. This is useful if the attack volume exceeds your internet capacity. This works by advertising with BGP a route to the attacked user with a specific community. The border router modifies the next hop address of these routes to a specific IP address configured to forward the traffic to a null interface. RFC 7999 defines 65535:666 for this purpose. This is known as a remote-triggered blackhole (RTBH) and is explained in more detail in RFC 3882. It is also possible to blackhole the source of the attacks by leveraging unicast Reverse Path Forwarding (uRPF) from RFC 3704, as explained in RFC 5635. However, uRPF can be a serious tax on your router resources. See NCS5500 uRPF: Configuration and Impact on Scale for an example of the kind of restrictions you have to expect when enabling uRPF. On the advertising side, we can use BIRD. Here is a complete configuration file to allow any router to collect them:

log stderr all;
router id 192.0.2.1;
protocol device  
  scan time 10;
 
protocol bgp exporter  
  ipv4  
    import none;
    export where proto = "blackhole4";
   ;
  ipv6  
    import none;
    export where proto = "blackhole6";
   ;
  local as 64666;
  neighbor range 192.0.2.0/24 external;
  multihop;
  dynamic name "exporter";
  dynamic name digits 2;
  graceful restart yes;
  graceful restart time 0;
  long lived graceful restart yes;
  long lived stale time 3600;  # keep routes for 1 hour!
 
protocol static blackhole4  
  ipv4;
  route 203.0.113.206/32 blackhole  
    bgp_community.add((65535, 666));
   ;
  route 203.0.113.68/32 blackhole  
    bgp_community.add((65535, 666));
   ;
 
protocol static blackhole6  
  ipv6;
 

We use BGP long-lived graceful restart to ensure routes are kept for one hour, even if the BGP connection goes down, notably during maintenance. On the receiver side, if you have a Cisco router running IOS XR, you can use the following configuration to blackhole traffic received on the BGP session. As the BGP session is dedicated to this usage, The community is not used, but you can also forward these routes to your transit providers.

router static
 vrf public
  address-family ipv4 unicast
   192.0.2.1/32 Null0 description "BGP blackhole"
  !
  address-family ipv6 unicast
   2001:db8::1/128 Null0 description "BGP blackhole"
  !
 !
!
route-policy blackhole_ipv4_in_public
  if destination in (0.0.0.0/0 le 31) then
    drop
  endif
  set next-hop 192.0.2.1
  done
end-policy
!
route-policy blackhole_ipv6_in_public
  if destination in (::/0 le 127) then
    drop
  endif
  set next-hop 2001:db8::1
  done
end-policy
!
router bgp 12322
 neighbor-group BLACKHOLE_IPV4_PUBLIC
  remote-as 64666
  ebgp-multihop 255
  update-source Loopback10
  address-family ipv4 unicast
   maximum-prefix 100 90
   route-policy blackhole_ipv4_in_public in
   route-policy drop out
   long-lived-graceful-restart stale-time send 86400 accept 86400
  !
  address-family ipv6 unicast
   maximum-prefix 100 90
   route-policy blackhole_ipv6_in_public in
   route-policy drop out
   long-lived-graceful-restart stale-time send 86400 accept 86400
  !
 !
 vrf public
  neighbor 192.0.2.1
   use neighbor-group BLACKHOLE_IPV4_PUBLIC
   description akvorado-1

When the traffic is blackholed, it is still reported by IPFIX and sFlow. In Akvorado, use ForwardingStatus >= 128 as a filter. While this method is compatible with all routers, it makes the attack successful as the target is completely unreachable. If your router supports it, Flowspec can selectively filter flows to stop the attack without impacting the customer.

Flowspec Flowspec is defined in RFC 8955 and enables the transmission of flow specifications in BGP sessions. A flow specification is a set of matching criteria to apply to IP traffic. These criteria include the source and destination prefix, the IP protocol, the source and destination port, and the packet length. Each flow specification is associated with an action, encoded as an extended community: traffic shaping, traffic marking, or redirection. To announce flow specifications with BIRD, we extend our configuration. The extended community used shapes the matching traffic to 0 bytes per second.

flow4 table flowtab4;
flow6 table flowtab6;
protocol bgp exporter  
  flow4  
    import none;
    export where proto = "flowspec4";
   ;
  flow6  
    import none;
    export where proto = "flowspec6";
   ;
  # [ ]
 
protocol static flowspec4  
  flow4;
  route flow4  
    dst 203.0.113.68/32;
    sport = 53;
    length >= 1476 && <= 1500;
    proto = 17;
   
    bgp_ext_community.add((generic, 0x80060000, 0x00000000));
   ;
  route flow4  
    dst 203.0.113.206/32;
    sport = 123;
    length = 468;
    proto = 17;
   
    bgp_ext_community.add((generic, 0x80060000, 0x00000000));
   ;
 
protocol static flowspec6  
  flow6;
 

If you have a Cisco router running IOS XR, the configuration may look like this:

vrf public
 address-family ipv4 flowspec
 address-family ipv6 flowspec
!
router bgp 12322
 address-family vpnv4 flowspec
 address-family vpnv6 flowspec
 neighbor-group FLOWSPEC_IPV4_PUBLIC
  remote-as 64666
  ebgp-multihop 255
  update-source Loopback10
  address-family ipv4 flowspec
   long-lived-graceful-restart stale-time send 86400 accept 86400
   route-policy accept in
   route-policy drop out
   maximum-prefix 100 90
   validation disable
  !
  address-family ipv6 flowspec
   long-lived-graceful-restart stale-time send 86400 accept 86400
   route-policy accept in
   route-policy drop out
   maximum-prefix 100 90
   validation disable
  !
 !
 vrf public
  address-family ipv4 flowspec
  address-family ipv6 flowspec
  neighbor 192.0.2.1
   use neighbor-group FLOWSPEC_IPV4_PUBLIC
   description akvorado-1

Then, you need to enable Flowspec on all interfaces with:

flowspec
 vrf public
  address-family ipv4
   local-install interface-all
  !
  address-family ipv6
   local-install interface-all
  !
 !
!

As with the RTBH setup, you can filter dropped flows with ForwardingStatus >= 128.

DDoS detection (continued) In the example using Flowspec, the flows were also filtered on the length of the packet:

route flow4  
  dst 203.0.113.68/32;
  sport = 53;
  length >= 1476 && <= 1500;
  proto = 17;
 
  bgp_ext_community.add((generic, 0x80060000, 0x00000000));
 ;

This is an important addition: legitimate DNS requests are smaller than this and therefore not filtered.² With ClickHouse, you can get the 10^th and 90^th percentiles of the packet sizes with quantiles(0.1, 0.9)(Bytes/Packets). The last issue we need to tackle is how to optimize the request: it may need several seconds to collect the data and it is likely to consume substantial resources from your ClickHouse database. One solution is to create a materialized view to pre-aggregate results:

CREATE TABLE ddos_logs (
  TimeReceived DateTime,
  DstAddr IPv6,
  Proto UInt32,
  SrcPort UInt16,
  Gbps SimpleAggregateFunction(sum, Float64),
  Mpps SimpleAggregateFunction(sum, Float64),
  sources AggregateFunction(uniqCombined(12), IPv6),
  countries AggregateFunction(uniqCombined(12), FixedString(2)),
  size AggregateFunction(quantiles(0.1, 0.9), UInt64)
) ENGINE = SummingMergeTree
PARTITION BY toStartOfHour(TimeReceived)
ORDER BY (TimeReceived, DstAddr, Proto, SrcPort)
TTL toStartOfHour(TimeReceived) + INTERVAL 6 HOUR DELETE ;
CREATE MATERIALIZED VIEW ddos_logs_view TO ddos_logs AS
  SELECT
    toStartOfMinute(TimeReceived) AS TimeReceived,
    DstAddr,
    Proto,
    SrcPort,
    sum(((((Bytes * SamplingRate) * 8) / 1000) / 1000) / 1000) / 60 AS Gbps,
    sum(((Packets * SamplingRate) / 1000) / 1000) / 60 AS Mpps,
    uniqCombinedState(12)(SrcAddr) AS sources,
    uniqCombinedState(12)(SrcCountry) AS countries,
    quantilesState(0.1, 0.9)(toUInt64(Bytes/Packets)) AS size
  FROM flows
  WHERE DstNetRole = 'customers'
  GROUP BY
    TimeReceived,
    DstAddr,
    Proto,
    SrcPort

The ddos_logs table is using the SummingMergeTree engine. When the table receives new data, ClickHouse replaces all the rows with the same sorting key, as defined by the ORDER BY directive, with one row which contains summarized values using either the sum() function or the explicitly specified aggregate function (uniqCombined and quantiles in our example).³ Finally, we can modify our initial query with the following one:

SELECT *
FROM (
  SELECT
    TimeReceived,
    DstAddr,
    dictGetOrDefault('protocols', 'name', Proto, '???') AS Proto,
    SrcPort,
    sum(Gbps) AS Gbps,
    sum(Mpps) AS Mpps,
    uniqCombinedMerge(12)(sources) AS sources,
    uniqCombinedMerge(12)(countries) AS countries,
    quantilesMerge(0.1, 0.9)(size) AS size
  FROM ddos_logs
  WHERE TimeReceived > now() - INTERVAL 60 MINUTE
  GROUP BY
    TimeReceived,
    DstAddr,
    Proto,
    SrcPort
)
WHERE (Gbps > 1)
   OR ((Proto = 'UDP') AND (Gbps > 0.2)) 
   OR ((sources > 20) AND (Gbps > 0.1)) 
   OR ((countries > 10) AND (Gbps > 0.1))
ORDER BY
  TimeReceived DESC,
  Gbps DESC

Gluing everything together To sum up, building an anti-DDoS system requires to following these steps:

1. define a set of criteria to detect a DDoS attack,
2. translate these criteria into SQL requests,
3. pre-aggregate flows into SummingMergeTree tables,
4. query and transform the results to a BIRD configuration file, and
5. configure your routers to pull the routes from BIRD.

A Python script like the following one can handle the fourth step. For each attacked target, it generates both a Flowspec rule and a blackhole route.

import socket
import types
from clickhouse_driver import Client as CHClient
# Put your SQL query here!
SQL_QUERY = " "
# How many anti-DDoS rules we want at the same time?
MAX_DDOS_RULES = 20
def empty_ruleset():
    ruleset = types.SimpleNamespace()
    ruleset.flowspec = types.SimpleNamespace()
    ruleset.blackhole = types.SimpleNamespace()
    ruleset.flowspec.v4 = []
    ruleset.flowspec.v6 = []
    ruleset.blackhole.v4 = []
    ruleset.blackhole.v6 = []
    return ruleset
current_ruleset = empty_ruleset()
client = CHClient(host="clickhouse.akvorado.net")
while True:
    results = client.execute(SQL_QUERY)
    seen =  
    new_ruleset = empty_ruleset()
    for (t, addr, proto, port, gbps, mpps, sources, countries, size) in results:
        if (addr, proto, port) in seen:
            continue
        seen[(addr, proto, port)] = True
        # Flowspec
        if addr.ipv4_mapped:
            address = addr.ipv4_mapped
            rules = new_ruleset.flowspec.v4
            table = "flow4"
            mask = 32
            nh = "proto"
        else:
            address = addr
            rules = new_ruleset.flowspec.v6
            table = "flow6"
            mask = 128
            nh = "next header"
        if size[0] == size[1]:
            length = f"length =  int(size[0]) "
        else:
            length = f"length >=  int(size[0])  && <=  int(size[1]) "
        header = f"""
# Time:  t 
# Source:  address , protocol:  proto , port:  port 
# Gbps/Mpps:  gbps:.3 / mpps:.3 , packet size:  int(size[0]) <=X<= int(size[1]) 
# Flows:  flows , sources:  sources , countries:  countries 
"""
        rules.append(
                f""" header 
route  table   
  dst  address / mask ;
  sport =  port ;
   length ;
   nh  =  socket.getprotobyname(proto) ;
 
  bgp_ext_community.add((generic, 0x80060000, 0x00000000));
 ;
"""
        )
        # Blackhole
        if addr.ipv4_mapped:
            rules = new_ruleset.blackhole.v4
        else:
            rules = new_ruleset.blackhole.v6
        rules.append(
            f""" header 
route  address / mask  blackhole  
  bgp_community.add((65535, 666));
 ;
"""
        )
        new_ruleset.flowspec.v4 = list(
            set(new_ruleset.flowspec.v4[:MAX_DDOS_RULES])
        )
        new_ruleset.flowspec.v6 = list(
            set(new_ruleset.flowspec.v6[:MAX_DDOS_RULES])
        )
        # TODO: advertise changes by mail, chat, ...
        current_ruleset = new_ruleset
        changes = False
        for rules, path in (
            (current_ruleset.flowspec.v4, "v4-flowspec"),
            (current_ruleset.flowspec.v6, "v6-flowspec"),
            (current_ruleset.blackhole.v4, "v4-blackhole"),
            (current_ruleset.blackhole.v6, "v6-blackhole"),
        ):
            path = os.path.join("/etc/bird/", f" path .conf")
            with open(f" path .tmp", "w") as f:
                for r in rules:
                    f.write(r)
            changes = (
                changes or not os.path.exists(path) or not samefile(path, f" path .tmp")
            )
            os.rename(f" path .tmp", path)
        if not changes:
            continue
        proc = subprocess.Popen(
            ["birdc", "configure"],
            stdin=subprocess.DEVNULL,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
        )
        stdout, stderr = proc.communicate(None)
        stdout = stdout.decode("utf-8", "replace")
        stderr = stderr.decode("utf-8", "replace")
        if proc.returncode != 0:
            logger.error(
                "  error:\n \n ".format(
                    "birdc reconfigure",
                    "\n".join(
                        [" O:  ".format(line) for line in stdout.rstrip().split("\n")]
                    ),
                    "\n".join(
                        [" E:  ".format(line) for line in stderr.rstrip().split("\n")]
                    ),
                )
            )

---

Until Akvorado integrates DDoS detection and mitigation, the ideas presented in this blog post provide a solid foundation to get started with your own anti-DDoS system.

---

1. ClickHouse can export results using Markdown format when appending FORMAT Markdown to the query.
2. While most DNS clients should retry with TCP on failures, this is not always the case: until recently, musl libc did not implement this.
3. The materialized view also aggregates the data at hand, both for efficiency and to ensure we work with the right data types.

import/jon/amex/%.journal: import/jon/amex/%.csv rules/amex.csv.rules
    rm -f $(@D)/.latest.$*.csv $@
    hledger import --rules-file rules/amex.csv.rules -f $@ $<

import/opening/2023.csv: 2022.journal
    mkdir -p import/opening
    hledger bal -f $< \
                $(list_of_accounts_I_want_to_carry_over) \
        -O csv -N > $@
import/opening/2023.journal: import/opening/2023.csv rules/opening.rules
    rm -f $(@D)/.latest.2023.csv $@
    hledger import --rules-file rules/opening.rules \
        -f $@ $<

2022-01-02 ZTL*RELISH
    family:liabilities:creditcard        -3.00
    family:dues:jon                       3.00
    (jon:expenses:snacks)                 3.00

2022-01-02 ZTL*RELISH
    family:liabilities:creditcard        -3.00
    family:liabilities:jon:snacks

$ head flow-4.proto
syntax = "proto3";
package decoder;
option go_package = "akvorado/inlet/flow/decoder";
message FlowMessagev4  
  uint64 TimeReceived = 2;
  uint32 SequenceNum = 3;
  uint64 SamplingRate = 4;
  uint32 FlowDirection = 5;
$ protoc -I=. --plugin=protoc-gen-go --go_out=module=akvorado:. flow-4.proto
$ head inlet/flow/decoder/flow-4.pb.go
// Code generated by protoc-gen-go. DO NOT EDIT.
// versions:
//      protoc-gen-go v1.28.0
//      protoc        v3.21.12
// source: inlet/flow/data/schemas/flow-4.proto
package decoder
import (
        protoreflect "google.golang.org/protobuf/reflect/protoreflect"

goos: linux
goarch: amd64
pkg: akvorado/inlet/flow
cpu: AMD Ryzen 5 5600X 6-Core Processor
                              initial.txt                 final.txt               
                                 sec/op        sec/op     vs base                 
Netflow/with_encoding-12      12.963    2%   7.836    1%  -39.55% (p=0.000 n=10)
Sflow/with_encoding-12         19.37    1%   10.15    2%  -47.63% (p=0.000 n=10)

Faster Protocol Buffers encoding I use the following code to benchmark both the decoding and encoding process. Initially, the Decode() method is a thin layer above GoFlow2 producer and stores the decoded data into the in-memory structure generated by protoc. Later, some of the data will be encoded directly during flow decoding. This is why we measure both the decoding and the encoding.²

func BenchmarkDecodeEncodeSflow(b *testing.B)  
    r := reporter.NewMock(b)
    sdecoder := sflow.New(r)
    data := helpers.ReadPcapPayload(b,
        filepath.Join("decoder", "sflow", "testdata", "data-1140.pcap"))
    for _, withEncoding := range []bool true, false   
        title := map[bool]string 
            true:  "with encoding",
            false: "without encoding",
         [withEncoding]
        var got []*decoder.FlowMessage
        b.Run(title, func(b *testing.B)  
            for i := 0; i < b.N; i++  
                got = sdecoder.Decode(decoder.RawFlow 
                    Payload: data,
                    Source: net.ParseIP("127.0.0.1"),
                 )
                if withEncoding  
                    for _, flow := range got  
                        buf := []byte 
                        buf = protowire.AppendVarint(buf, uint64(proto.Size(flow)))
                        proto.MarshalOptions .MarshalAppend(buf, flow)
                     
                 
             
         )
     
 

The canonical Go implementation for Protocol Buffers, google.golang.org/protobuf is not the most efficient one. For a long time, people were relying on gogoprotobuf. However, the project is now deprecated. A good replacement is vtprotobuf.³

goos: linux
goarch: amd64
pkg: akvorado/inlet/flow
cpu: AMD Ryzen 5 5600X 6-Core Processor
                              initial.txt               bench-2.txt              
                                sec/op        sec/op     vs base                 
Netflow/with_encoding-12      12.96    2%   10.28    2%  -20.67% (p=0.000 n=10)
Netflow/without_encoding-12   8.935    2%   8.975    2%        ~ (p=0.143 n=10)
Sflow/with_encoding-12        19.37    1%   16.67    2%  -13.93% (p=0.000 n=10)
Sflow/without_encoding-12     14.62    3%   14.87    1%   +1.66% (p=0.007 n=10)

Dynamic Protocol Buffers encoding We have our baseline. Let s see how to encode our Protocol Buffers without a .proto file. The wire format is simple and rely a lot on variable-width integers. Variable-width integers, or varints, are an efficient way of encoding unsigned integers using a variable number of bytes, from one to ten, with small values using fewer bytes. They work by splitting integers into 7-bit payloads and using the 8^th bit as a continuation indicator, set to 1 for all payloads except the last.

Variable-width integers encoding in Protocol Buffers

For our usage, we only need two types: variable-width integers and byte sequences. A byte sequence is encoded by prefixing it by its length as a varint. When a message is encoded, each key-value pair is turned into a record consisting of a field number, a wire type, and a payload. The field number and the wire type are encoded as a single variable-width integer called a tag.

Message encoded with Protocol Buffers

We use the following low-level functions to build the output buffer:

• protowire.AppendTag() encodes a tag,
• protowire.AppendVarint() encodes a variable-width integer, and
• protowire.AppendBytes() append bytes as is.

Our schema abstraction contains the appropriate information to encode a message (ProtobufIndex) and to generate a proto definition file (fields starting with Protobuf):

type Column struct  
    Key       ColumnKey
    Name      string
    Disabled  bool
    // [ ]
    // For protobuf.
    ProtobufIndex    protowire.Number
    ProtobufType     protoreflect.Kind // Uint64Kind, Uint32Kind,  
    ProtobufEnum     map[int]string
    ProtobufEnumName string
    ProtobufRepeated bool
 

We have a few helper methods around the protowire functions to directly encode the fields while decoding the flows. They skip disabled fields or non-repeated fields already encoded. Here is an excerpt of the sFlow decoder:

sch.ProtobufAppendVarint(bf, schema.ColumnBytes, uint64(recordData.Base.Length))
sch.ProtobufAppendVarint(bf, schema.ColumnProto, uint64(recordData.Base.Protocol))
sch.ProtobufAppendVarint(bf, schema.ColumnSrcPort, uint64(recordData.Base.SrcPort))
sch.ProtobufAppendVarint(bf, schema.ColumnDstPort, uint64(recordData.Base.DstPort))
sch.ProtobufAppendVarint(bf, schema.ColumnEType, helpers.ETypeIPv4)

For fields that are required later in the pipeline, like source and destination addresses, they are stored unencoded in a separate structure:

type FlowMessage struct  
    TimeReceived uint64
    SamplingRate uint32
    // For exporter classifier
    ExporterAddress netip.Addr
    // For interface classifier
    InIf  uint32
    OutIf uint32
    // For geolocation or BMP
    SrcAddr netip.Addr
    DstAddr netip.Addr
    NextHop netip.Addr
    // Core component may override them
    SrcAS     uint32
    DstAS     uint32
    GotASPath bool
    // protobuf is the protobuf representation for the information not contained above.
    protobuf      []byte
    protobufSet   bitset.BitSet
 

The protobuf slice holds encoded data. It is initialized with a capacity of 500 bytes to avoid resizing during encoding. There is also some reserved room at the beginning to be able to encode the total size as a variable-width integer. Upon finalizing encoding, the remaining fields are added and the message length is prefixed:

func (schema *Schema) ProtobufMarshal(bf *FlowMessage) []byte  
    schema.ProtobufAppendVarint(bf, ColumnTimeReceived, bf.TimeReceived)
    schema.ProtobufAppendVarint(bf, ColumnSamplingRate, uint64(bf.SamplingRate))
    schema.ProtobufAppendIP(bf, ColumnExporterAddress, bf.ExporterAddress)
    schema.ProtobufAppendVarint(bf, ColumnSrcAS, uint64(bf.SrcAS))
    schema.ProtobufAppendVarint(bf, ColumnDstAS, uint64(bf.DstAS))
    schema.ProtobufAppendIP(bf, ColumnSrcAddr, bf.SrcAddr)
    schema.ProtobufAppendIP(bf, ColumnDstAddr, bf.DstAddr)
    // Add length and move it as a prefix
    end := len(bf.protobuf)
    payloadLen := end - maxSizeVarint
    bf.protobuf = protowire.AppendVarint(bf.protobuf, uint64(payloadLen))
    sizeLen := len(bf.protobuf) - end
    result := bf.protobuf[maxSizeVarint-sizeLen : end]
    copy(result, bf.protobuf[end:end+sizeLen])
    return result
 

Minimizing allocations is critical for maintaining encoding performance. The benchmark tests should be run with the -benchmem flag to monitor allocation numbers. Each allocation incurs an additional cost to the garbage collector. The Go profiler is a valuable tool for identifying areas of code that can be optimized:

$ go test -run=__nothing__ -bench=Netflow/with_encoding \
>         -benchmem -cpuprofile profile.out \
>         akvorado/inlet/flow
goos: linux
goarch: amd64
pkg: akvorado/inlet/flow
cpu: AMD Ryzen 5 5600X 6-Core Processor
Netflow/with_encoding-12             143953              7955 ns/op            8256 B/op        134 allocs/op
PASS
ok      akvorado/inlet/flow     1.418s
$ go tool pprof profile.out
File: flow.test
Type: cpu
Time: Feb 4, 2023 at 8:12pm (CET)
Duration: 1.41s, Total samples = 2.08s (147.96%)
Entering interactive mode (type "help" for commands, "o" for options)
(pprof) web

After using the internal schema instead of code generated from the proto definition file, the performance improved. However, this comparison is not entirely fair as less information is being decoded and previously GoFlow2 was decoding to its own structure, which was then copied to our own version.

goos: linux
goarch: amd64
pkg: akvorado/inlet/flow
cpu: AMD Ryzen 5 5600X 6-Core Processor
                              bench-2.txt                bench-3.txt              
                                 sec/op        sec/op     vs base                 
Netflow/with_encoding-12      10.284    2%   7.758    3%  -24.56% (p=0.000 n=10)
Netflow/without_encoding-12    8.975    2%   7.304    2%  -18.61% (p=0.000 n=10)
Sflow/with_encoding-12         16.67    2%   14.26    1%  -14.50% (p=0.000 n=10)
Sflow/without_encoding-12      14.87    1%   13.56    2%   -8.80% (p=0.000 n=10)

As for testing, we use github.com/jhump/protoreflect: the protoparse package parses the proto definition file we generate and the dynamic package decodes the messages. Check the ProtobufDecode() method for more details.⁴ To get the final figures, I have also optimized the decoding in GoFlow2. It was relying heavily on binary.Read(). This function may use reflection in certain cases and each call allocates a byte array to read data. Replacing it with a more efficient version provides the following improvement:

goos: linux
goarch: amd64
pkg: akvorado/inlet/flow
cpu: AMD Ryzen 5 5600X 6-Core Processor
                              bench-3.txt                bench-4.txt              
                                 sec/op        sec/op     vs base                 
Netflow/with_encoding-12       7.758    3%   7.365    2%   -5.07% (p=0.000 n=10)
Netflow/without_encoding-12    7.304    2%   6.931    3%   -5.11% (p=0.000 n=10)
Sflow/with_encoding-12        14.256    1%   9.834    2%  -31.02% (p=0.000 n=10)
Sflow/without_encoding-12     13.559    2%   9.353    2%  -31.02% (p=0.000 n=10)

It is now easier to collect new data and the inlet component is faster!

Notice Some paragraphs were editorialized by ChatGPT, using editorialize and keep it short as a prompt. The result was proofread by a human for correctness. The main idea is that ChatGPT should be better at English than me.

---

1. While empty fields are not serialized to Protocol Buffers, empty columns in ClickHouse take some space, even if they compress well. Moreover, unused fields are still decoded and they may clutter the interface.
2. There is a similar function using NetFlow. NetFlow and IPFIX protocols are less complex to decode than sFlow as they are using a simpler TLV structure.
3. vtprotobuf generates more optimized Go code by removing an abstraction layer. It directly generates the code encoding each field to bytes:

   if m.OutIfSpeed != 0  
       i = encodeVarint(dAtA, i, uint64(m.OutIfSpeed))
       i--
       dAtA[i] = 0x6
       i--
       dAtA[i] = 0xd8
    
   

4. There is also a protoprint package to generate proto definition file. I did not use it.

The world is made up of four elements: Earth, Air, Fire, and Water. This is a fact well known even to Corporal Nobbs. It's also wrong. There's a fifth element, and generally it's called Surprise. For example, the dwarfs found out how to turn lead into gold by doing it the hard way. The difference between that and the easy way is that the hard way works.

How do set it up I ve talked about most of the pieces here already:

• Delta Chat, which is an IM app that uses mail servers (SMTP and IMAP) as transport, and OpenPGP encryption for security.
• One of the items I highlighted in Tools for Communicating Offline and in Difficult Circumstances, such as:
  • NNCP, which I have talked about a lot. NNCP can run atop a network, over USB drives (sneakernet) (even airgapped), and over many other transports.
  • Syncthing, which can form an ad-hoc mesh.
  • Filespooler, which handles remote command execution, and can use a transport such as Syncthing or NNCP to get messages to their destination.
  • Yggdrasil, which forms an auto-mesh network over things like ad-hoc wifi. It s not asynchronous itself, but its properties may be used to build an asyncrhonous email network email itself can be asynchronous across any carrier. Others such as Tor could also be used.
  • And various other physical carriers such as LoRa and XBee SX radios.
• Email servers. For instance, there are existing instructions for running Postfix or Exim over NNCP. These can be easily adapted to run across something like Filespooler instead. These can be run locally on a laptop, or, with a tool such as Termux, on Android.

So, putting this together:

• All Delta Chat needs is access to a SMTP and IMAP server. This server could easily reside on localhost.
• Existing email servers support transport of email using non-IP transports, including batch transports that can easily store it in files.
• These batches can be easily carried by NNCP, Syncthing, Filespooler, etc. Or, if the connectivity is good enough, via traditional networking using Yggdrasil.
  • Side note: Both NNCP and email servers support various routing arrangements, and can easily use intermediary routing nodes. Syncthing can also mesh. NNCP supports asynchronous multicast, letting your messages opportunistically find the best way to their destination.

OK, so why would you do it? You might be thinking, doesn t asynchronous mean slow? Well, not necessarily. Asynchronous means reliability is more important than speed ; that is, slow (even to the point of weeks) is acceptable, but not required. NNCP and Syncthing, for instance, can easily deliver within a couple of seconds. But let s step back a bit. Let s say you re hiking in the wilderness in an area with no connectivity. You get back to your group at a campsite at the end of the day, and have taken some photos of the forest and sent them to some friends. Some of those friends are at the campsite; when you get within signal range, they get your messages right away. Some of those friends are in another country. So one person from your group drives into town and sits at a coffee shop for a few minutes, connected to their wifi. All the messages from everyone in the group go out, all the messages from outside the group come in. Then they go back to camp and the devices exchange messages. Pretty slick, eh?

---

Note: this article also has a more permanent home on my website, where it may be periodically updated.

The Road to Gandolfo I think I had read this book almost 10-12 years back and somehow ended up reading it up again. Apparently, he had put this fiction, story, book under some other pen name earlier. It is possible that I might have read it under that name and hence forgotten all about it. This book/story is full of innuendo, irony, sarcasm and basically the thrill of life. There are two main characters in the book, the first is General Mackenzie who has spent almost 3 to 4 decades being a spy/a counterintelligence expert in the Queen s service. And while he outclasses them all even at the ripe age of 50, he is thrown out under the pretext of conduct unbecoming of an officer. The other main character is Sam Devereaux. This gentleman is an army lawyer and is basically counting the days when he completes his tour of duty as a military lawyer and start his corporate civil law with somebody he knows. It is much to his dismay that while under a week is left for his tour of duty to be left over he is summoned to try and extradite General MacKenzie who has been put on house arrest. Apparently, in China there was a sculpture of a great Chinese gentleman in the nude. For reasons unknown or rather not being shared herein, he basically breaks part of the sculpture. This of course, enrages the Chinese and they call it a diplomatic accident and try to put the General into house arrest. Unfortunately for both the General and his captors, he decides to escape/go for it. While he does succeed entering the American embassy, he finds himself to be person non-grata and is thrown back outside where the Chinese recapture him. This is where the Embassy & the Govt. decide it would be better if somehow the General could be removed from China permanently so he doesn t cause any further diplomatic accidents. In order to do that Sam s services are bought. Now in order to understand the General, Sam learns that he has 4 ex-wives. He promptly goes and meet them to understand why the general behaved as he did. He apparently also peed on the American flag. To his surprise, all the four ex-wives are still very much in with the general. During the course of interviewing the ladies he is seduced by them and also gives names to their chests in order to differentiate between each one of them. Later he is seduced by the eldest of the four wives and they spend the evening together. Next day Sam meets and is promptly manhandled by the general and the diplomatic papers are seen by the general. After meeting the general and the Chinese counterpart, they quickly agree to extradite him as they do not know how to keep the general control. During his stay of house arrest, the General reads one of the communist rags as he puts it and gets the idea to kidnap the pope and that forms the basis of the story. Castel Gandolfo seems to be a real place which is in Italy and is apparently is the papal residence where s/he goes to reside every winter. The book is written in 1976 hence in the book, the General decides to form a corporation for which he would raise funds in order to make the kidnapping. The amount in 1976 was 40 million dollars and it was a big sum, to be with times, let s think of say 40 billion dollars so gets the scale of things. Now while a part of me wants to tell the rest of the story, the story isn t really mine to tell. Read The Road to Gandolfo for the rest. While I can t guarantee you much, I can say you might find yourself constantly amused by the antics of both the General, Sam and the General s ex-wives. There are also a few minute characters that you will meet on the way, hope you discover them and enjoy it immensely as I have. One thing I have to say, while I was reading it, I very much got vibes of Not a penny more, not a penny less by Jeffrey Archer. As shared before, lots of twists and turns, enjoy the ride

Webforms Webforms are nothing but a form you fill on the web or www. Webforms are and were a thing from early 90s to today. I was supposed to register for https://www.swavlambancard.gov.in/ almost a month back but procrastinated till few couple of days back and with good reason. I was hoping one of my good friends would help me but they had their own thing. So finally, I tried to fill the form few days back. It took me almost 30 odd attempts to finally fill the form and was given an enrollment number. Why it took me 30 odd attempts and with what should tell you the reason

1. I felt like I was filling the form from 1990 s rather than today because
   
2. The form doesn t know either its state or saves data during a session This lesson has been learned a long time back by almost all service providers except Govt. of India. Both the browsers on a mobile as well as desktop can save data during session. If you don t know what I mean by that go to about:preferences#privacy in Firefox and look at Manage Data. There you will find most sites do put some data along with cookies arguably to help make your web experience better. Chrome or Chromium has the same thing perhaps shared under a different name but its the same thing. But that is not all.
   
3. None of the fields have any verification. The form is of 3 pages. The verification at the end of the document doesn t tell you what is wrong and what needs to be corrected. Really think on this, I am on a 24 LED monitor and I m filling the form and I had to do it at least 20-30 times before it was accepted. And guess what, I have no clue even about why it was selected. The same data, the same everything and after the nth time it accepted. Now if I am facing such a problem when I have some idea how technology works somewhat how are people who are trying to fill this form on 6 mobiles supposed to do? And many of them not at all clued in technology as I am.
   

I could go on outlining many of the issues that I faced but they are all similar in many ways the problems faced while filling the NEW Income Tax forms. Of course the New Income Tax portal is a whole ball-game in itself as it gives new errors every time instead of solving them. Most C.A. s have turned to third-party xml tools that enable you to upload xml compliant data to the New Income tax portal but this is for businesses and those who can afford it. Again, even that is in a sort of messy state but that is a whole another tale altogether. One of the reasons to my mind why the forms are designed the way they are so that people go to specific cybercafes or get individual people to fill and upload it and make more money. I was told to go to a specific cybercafe and meet a certain individual and he asked for INR 500/- to do the work. While I don t have financial problems, I was more worried about my data going into the wrong hands. But I can see a very steady way to make money without doing much hard work.

Hearing Loss info. Now because I had been both to Kamla Nehru Hospital as well as Sasoon and especially the deaf department, I saw many kids with half-formed ears. I had asked the doctors and they had shared this is due to malnutrition. We do know that women during pregnancies need more calories, more everything as they are eating for two bodies, not one. And this is large-scale, apparently more than 5 percent of population have children like this. And this number was of 2014, what is it today nobody knows. I also came to know that at least for some people like me, due to Covid they became deaf. I had asked the doctors if they knew of people who had become deaf due to Covid. They basically replied in the negative as they don t have the resources to monitor the same. The Govt. has an idea of health ID but just like Aadhar has to many serious sinister implications. Somebody had shared with me a long time back that in India systems work inspite of Govt. machinery rather than because of it. Meaning that the Government itself ties itself into several knots and then people have to be creative to try and figure a way out to help people. I found another issue while dealing with them. Apparently, even though I have 60% hearing loss I would be given a certificate of 40% hearing loss and they call it Temporary Progressive Loss. I saw almost all the people who had come, many of them having far severe defencies than me getting the same/similar certificate. All of them got Temporary Progressive. Some of the cases were real puzzling. For e.g. I met another Agarwal who had a severe accident few months ago and there is some kind of paralysis & bone issue. The doctors have given up but even that gentleman was given Temporary Progressive. From what little I could understand, the idea is that over period if there is possibility of things becoming better then it should be given. Another gentleman suffered a case of dwarfism. Even he was given the same certificate. Think there have been orders from above so that people even having difficulties are not helped. Another point if you look in a macro sense, it presents a somewhat rosy picture. If someone were to debunk the Govt. data either from India or abroad then from GOI perspective they have an agenda even though the people who are suffering are our brothers and sisters And all of this is because I can read, write, articulate. Perhaps many of them may not even have a voice or a platform. Even to get this temporary progressive disability certificate there is more than 4 months of running from one place to the other, 4 months of culmination of work. This I can share and tell from my experience, who knows how much else others might have suffered for the same. In my case a review will happen after 5 years, in most other cases they have given only 1 year. Of course, this does justify people s jobs and perhaps partly it may be due to that. Such are times where I really miss that I am unable to hear otherwise could have fleshed out lot more other people s sufferings. And just so people know/understand this is happening in the heart of the city whose population easily exceeds 6 million plus and is supposed to be a progressive city. I do appreciate and understand the difficulties that the doctors are placed under.

Mum s Birthday & Social Engineering. While I don t want to get into details, in the last couple of weeks mum s birthday was there and that had totally escaped me. I have been trying to disassociate myself from her and at times it s hard and then you don t remember and somebody makes you remember. So, on one hand guilty, and the other do not know what to do. If she were alive I would have bought a piece of cake or something. Didn t feel like it, hence donated some money to the local aged home. This way at least I hope they have some semblance of peace. All of them are of her similar age group. The other thing that I began to observe in the earnest, fake identities have become the norm. Many people took elon musk s potrait using their own names in the handles, but even then Elon Free Speech Musk banned them. So much for free speech. Then I saw quite a few handles that have cute women as their profile picture but they are good at social engineering. This has started only a couple of weeks back and have seen quite a few handles leaving Twitter and joining Mastodon. Also, have been hearing that many admins of Mastodon pods are unable to get on top of this. Also, lot of people complaining as it isn t user-friendly UI as twitter is. Do they not realize that Twitter has its own IP and any competing network can t copy or infringe on their product. Otherwise, they will be sued like how Ford was & potentially win. I am not really gonna talk much about it as the blog post has become quite long and that needs its own post to do any sort of justice to it. Till later people

$ kubectl get pods -A
NAMESPACE     NAME                                       READY   STATUS    RESTARTS       AGE
kube-system   calico-kube-controllers-59697b644f-7fsln   1/1     Running   2 (119m ago)   7d
kube-system   calico-node-6ptsh                          1/1     Running   2 (119m ago)   7d
kube-system   calico-node-7x5j8                          1/1     Running   2 (119m ago)   7d
kube-system   calico-node-qlnf6                          1/1     Running   2 (119m ago)   7d
kube-system   coredns-565d847f94-79jlw                   1/1     Running   2 (119m ago)   7d
kube-system   coredns-565d847f94-fqwn4                   1/1     Running   2 (119m ago)   7d
kube-system   etcd-k8s-master                            1/1     Running   2 (119m ago)   7d
kube-system   kube-apiserver-k8s-master                  1/1     Running   2 (119m ago)   7d
kube-system   kube-controller-manager-k8s-master         1/1     Running   2 (119m ago)   7d
kube-system   kube-proxy-4n9b7                           1/1     Running   2 (119m ago)   7d
kube-system   kube-proxy-k4rzv                           1/1     Running   2 (119m ago)   7d
kube-system   kube-proxy-lz2dd                           1/1     Running   2 (119m ago)   7d
kube-system   kube-scheduler-k8s-master                  1/1     Running   2 (119m ago)   7d

$ curl --proto '=https' --tlsv1.2 -sSfL https://run.linkerd.io/install   sh

export PATH=$PATH:~/.linkerd2/bin/

$ linkerd version
Client version: stable-2.12.2
Server version: unavailable

$ linkerd check --pre
Linkerd core checks
===================

kubernetes-api
--------------
  can initialize the client
  can query the Kubernetes API

kubernetes-version
------------------
  is running the minimum Kubernetes API version
  is running the minimum kubectl version

pre-kubernetes-setup
--------------------
  control plane namespace does not already exist
  can create non-namespaced resources
  can create ServiceAccounts
  can create Services
  can create Deployments
  can create CronJobs
  can create ConfigMaps
  can create Secrets
  can read Secrets
  can read extension-apiserver-authentication configmap
  no clock skew detected

linkerd-version
---------------
  can determine the latest version
  cli is up-to-date

Status check results are  

$ linkerd install --crds   kubectl apply -f -
Rendering Linkerd CRDs...
Next, run  linkerd install   kubectl apply -f -  to install the control plane.

customresourcedefinition.apiextensions.k8s.io/authorizationpolicies.policy.linkerd.io created
customresourcedefinition.apiextensions.k8s.io/httproutes.policy.linkerd.io created
customresourcedefinition.apiextensions.k8s.io/meshtlsauthentications.policy.linkerd.io created
customresourcedefinition.apiextensions.k8s.io/networkauthentications.policy.linkerd.io created
customresourcedefinition.apiextensions.k8s.io/serverauthorizations.policy.linkerd.io created
customresourcedefinition.apiextensions.k8s.io/servers.policy.linkerd.io created
customresourcedefinition.apiextensions.k8s.io/serviceprofiles.linkerd.io created

$ linkerd install   kubectl apply -f -       
namespace/linkerd created
clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-identity created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-identity created
serviceaccount/linkerd-identity created
clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-destination created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-destination created
serviceaccount/linkerd-destination created
secret/linkerd-sp-validator-k8s-tls created
validatingwebhookconfiguration.admissionregistration.k8s.io/linkerd-sp-validator-webhook-config created
secret/linkerd-policy-validator-k8s-tls created
validatingwebhookconfiguration.admissionregistration.k8s.io/linkerd-policy-validator-webhook-config created
clusterrole.rbac.authorization.k8s.io/linkerd-policy created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-destination-policy created
role.rbac.authorization.k8s.io/linkerd-heartbeat created
rolebinding.rbac.authorization.k8s.io/linkerd-heartbeat created
clusterrole.rbac.authorization.k8s.io/linkerd-heartbeat created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-heartbeat created
serviceaccount/linkerd-heartbeat created
clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-proxy-injector created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-proxy-injector created
serviceaccount/linkerd-proxy-injector created
secret/linkerd-proxy-injector-k8s-tls created
mutatingwebhookconfiguration.admissionregistration.k8s.io/linkerd-proxy-injector-webhook-config created
configmap/linkerd-config created
secret/linkerd-identity-issuer created
configmap/linkerd-identity-trust-roots created
service/linkerd-identity created
service/linkerd-identity-headless created
deployment.apps/linkerd-identity created
service/linkerd-dst created
service/linkerd-dst-headless created
service/linkerd-sp-validator created
service/linkerd-policy created
service/linkerd-policy-validator created
deployment.apps/linkerd-destination created
cronjob.batch/linkerd-heartbeat created
deployment.apps/linkerd-proxy-injector created
service/linkerd-proxy-injector created
secret/linkerd-config-overrides created

$ kubectl get pods -A
...
linkerd       linkerd-destination-67b9cc8749-xqcbx       4/4     Running   0              69s
linkerd       linkerd-identity-59b46789cc-ntfcx          2/2     Running   0              69s
linkerd       linkerd-proxy-injector-7fc85556bf-vnvw6    1/2     Running   0              69s

$ linkerd check
Linkerd core checks
===================

kubernetes-api
--------------
  can initialize the client
  can query the Kubernetes API

kubernetes-version
------------------
  is running the minimum Kubernetes API version
  is running the minimum kubectl version

linkerd-existence
-----------------
  'linkerd-config' config map exists
  heartbeat ServiceAccount exist
  control plane replica sets are ready
  no unschedulable pods
  control plane pods are ready
  cluster networks contains all pods
  cluster networks contains all services

linkerd-config
--------------
  control plane Namespace exists
  control plane ClusterRoles exist
  control plane ClusterRoleBindings exist
  control plane ServiceAccounts exist
  control plane CustomResourceDefinitions exist
  control plane MutatingWebhookConfigurations exist
  control plane ValidatingWebhookConfigurations exist
  proxy-init container runs as root user if docker container runtime is used

linkerd-identity
----------------
  certificate config is valid
  trust anchors are using supported crypto algorithm
  trust anchors are within their validity period
  trust anchors are valid for at least 60 days
  issuer cert is using supported crypto algorithm
  issuer cert is within its validity period
  issuer cert is valid for at least 60 days
  issuer cert is issued by the trust anchor

linkerd-webhooks-and-apisvc-tls
-------------------------------
  proxy-injector webhook has valid cert
  proxy-injector cert is valid for at least 60 days
  sp-validator webhook has valid cert
  sp-validator cert is valid for at least 60 days
  policy-validator webhook has valid cert
  policy-validator cert is valid for at least 60 days

linkerd-version
---------------
  can determine the latest version
  cli is up-to-date

control-plane-version
---------------------
  can retrieve the control plane version
  control plane is up-to-date
  control plane and cli versions match

linkerd-control-plane-proxy
---------------------------
  control plane proxies are healthy
  control plane proxies are up-to-date
  control plane proxies and cli versions match

Status check results are  

$ linkerd viz install   kubectl apply -f -
namespace/linkerd-viz created
clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-viz-metrics-api created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-viz-metrics-api created
serviceaccount/metrics-api created
clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-viz-prometheus created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-viz-prometheus created
serviceaccount/prometheus created
clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-viz-tap created
clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-viz-tap-admin created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-viz-tap created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-viz-tap-auth-delegator created
serviceaccount/tap created
rolebinding.rbac.authorization.k8s.io/linkerd-linkerd-viz-tap-auth-reader created
secret/tap-k8s-tls created
apiservice.apiregistration.k8s.io/v1alpha1.tap.linkerd.io created
role.rbac.authorization.k8s.io/web created
rolebinding.rbac.authorization.k8s.io/web created
clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-viz-web-check created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-viz-web-check created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-viz-web-admin created
clusterrole.rbac.authorization.k8s.io/linkerd-linkerd-viz-web-api created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-linkerd-viz-web-api created
serviceaccount/web created
server.policy.linkerd.io/admin created
authorizationpolicy.policy.linkerd.io/admin created
networkauthentication.policy.linkerd.io/kubelet created
server.policy.linkerd.io/proxy-admin created
authorizationpolicy.policy.linkerd.io/proxy-admin created
service/metrics-api created
deployment.apps/metrics-api created
server.policy.linkerd.io/metrics-api created
authorizationpolicy.policy.linkerd.io/metrics-api created
meshtlsauthentication.policy.linkerd.io/metrics-api-web created
configmap/prometheus-config created
service/prometheus created
deployment.apps/prometheus created
service/tap created
deployment.apps/tap created
server.policy.linkerd.io/tap-api created
authorizationpolicy.policy.linkerd.io/tap created
clusterrole.rbac.authorization.k8s.io/linkerd-tap-injector created
clusterrolebinding.rbac.authorization.k8s.io/linkerd-tap-injector created
serviceaccount/tap-injector created
secret/tap-injector-k8s-tls created
mutatingwebhookconfiguration.admissionregistration.k8s.io/linkerd-tap-injector-webhook-config created
service/tap-injector created
deployment.apps/tap-injector created
server.policy.linkerd.io/tap-injector-webhook created
authorizationpolicy.policy.linkerd.io/tap-injector created
networkauthentication.policy.linkerd.io/kube-api-server created
service/web created
deployment.apps/web created
serviceprofile.linkerd.io/metrics-api.linkerd-viz.svc.cluster.local created
serviceprofile.linkerd.io/prometheus.linkerd-viz.svc.cluster.local created

$ kubectl get pods -A
...
linkerd-viz   prometheus-b5865f776-w5ssf                 1/2     Running   0              35s
linkerd-viz   tap-64f5c8597b-rqgbk                       2/2     Running   0              35s
linkerd-viz   tap-injector-7c75cfff4c-wl9mx              2/2     Running   0              34s
linkerd-viz   web-8c444745-jhzr5                         2/2     Running   0              34s

$ linkerd viz dashboard
Linkerd dashboard available at:
http://localhost:50750
Grafana dashboard available at:
http://localhost:50750/grafana
Opening Linkerd dashboard in the default browser
Opening in existing browser session.

$ cat deploy.yaml 
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - containerPort: 80

$ kubectl apply -f deploy.yaml

$ kubectl get pod nginx-deployment-cd55c47f5-cgxw2 -o yaml
apiVersion: v1
kind: Pod
metadata:
  annotations:
    cni.projectcalico.org/containerID: aee0295dda906f7935ce5c150ae30360005f5330e98c75a550b7cc0d1532f529
    cni.projectcalico.org/podIP: 172.16.36.89/32
    cni.projectcalico.org/podIPs: 172.16.36.89/32
  creationTimestamp: "2022-11-05T19:35:12Z"
  generateName: nginx-deployment-cd55c47f5-
  labels:
    app: nginx
    pod-template-hash: cd55c47f5
  name: nginx-deployment-cd55c47f5-cgxw2
  namespace: default
  ownerReferences:
  - apiVersion: apps/v1
    blockOwnerDeletion: true
    controller: true
    kind: ReplicaSet
    name: nginx-deployment-cd55c47f5
    uid: b604f5c4-f662-4333-aaa0-bd1a2b8b08c6
  resourceVersion: "22979"
  uid: 8fe30214-491b-4753-9fb2-485b6341376c
spec:
  containers:
  - image: nginx:latest
    imagePullPolicy: Always
    name: nginx
    ports:
    - containerPort: 80
      protocol: TCP
    resources:  
    terminationMessagePath: /dev/termination-log
    terminationMessagePolicy: File
    volumeMounts:
    - mountPath: /var/run/secrets/kubernetes.io/serviceaccount
      name: kube-api-access-2bt6z
      readOnly: true
  dnsPolicy: ClusterFirst
  enableServiceLinks: true
  nodeName: k8s-node1
  preemptionPolicy: PreemptLowerPriority
  priority: 0
  restartPolicy: Always
  schedulerName: default-scheduler
  securityContext:  
  serviceAccount: default
  serviceAccountName: default
  terminationGracePeriodSeconds: 30
  tolerations:
  - effect: NoExecute
    key: node.kubernetes.io/not-ready
    operator: Exists
    tolerationSeconds: 300
  - effect: NoExecute
    key: node.kubernetes.io/unreachable
    operator: Exists
    tolerationSeconds: 300
  volumes:
  - name: kube-api-access-2bt6z
    projected:
      defaultMode: 420
      sources:
      - serviceAccountToken:
          expirationSeconds: 3607
          path: token
      - configMap:
          items:
          - key: ca.crt
            path: ca.crt
          name: kube-root-ca.crt
      - downwardAPI:
          items:
          - fieldRef:
              apiVersion: v1
              fieldPath: metadata.namespace
            path: namespace
status:
  conditions:
  - lastProbeTime: null
    lastTransitionTime: "2022-11-05T19:35:12Z"
    status: "True"
    type: Initialized
  - lastProbeTime: null
    lastTransitionTime: "2022-11-05T19:35:16Z"
    status: "True"
    type: Ready
  - lastProbeTime: null
    lastTransitionTime: "2022-11-05T19:35:16Z"
    status: "True"
    type: ContainersReady
  - lastProbeTime: null
    lastTransitionTime: "2022-11-05T19:35:13Z"
    status: "True"
    type: PodScheduled
  containerStatuses:
  - containerID: containerd://f088f200315b44cbeed16499aba9b2d1396f9f81645e53b032d4bfa44166128a
    image: docker.io/library/nginx:latest
    imageID: docker.io/library/nginx@sha256:943c25b4b66b332184d5ba6bb18234273551593016c0e0ae906bab111548239f
    lastState:  
    name: nginx
    ready: true
    restartCount: 0
    started: true
    state:
      running:
        startedAt: "2022-11-05T19:35:15Z"
  hostIP: 192.168.2.216
  phase: Running
  podIP: 172.16.36.89
  podIPs:
  - ip: 172.16.36.89
  qosClass: BestEffort
  startTime: "2022-11-05T19:35:12Z"

$ kubectl get deploy nginx-deployment -o yaml   linkerd inject -   kubectl apply -f -

deployment "nginx-deployment" injected

deployment.apps/nginx-deployment configured

$ kubectl get pod nginx-deployment-858bdd545b-55jpf -o yaml
apiVersion: v1
kind: Pod
metadata:
  annotations:
    cni.projectcalico.org/containerID: 1ec3d345f859be8ead0374a7e880bcfdb9ba74a121b220a6fccbd342ac4b7ea8
    cni.projectcalico.org/podIP: 172.16.36.90/32
    cni.projectcalico.org/podIPs: 172.16.36.90/32
    linkerd.io/created-by: linkerd/proxy-injector stable-2.12.2
    linkerd.io/inject: enabled
    linkerd.io/proxy-version: stable-2.12.2
    linkerd.io/trust-root-sha256: 354fe6f49331e8e03d8fb07808e00a3e145d2661181cbfec7777b41051dc8e22
    viz.linkerd.io/tap-enabled: "true"
  creationTimestamp: "2022-11-05T19:44:15Z"
  generateName: nginx-deployment-858bdd545b-
  labels:
    app: nginx
    linkerd.io/control-plane-ns: linkerd
    linkerd.io/proxy-deployment: nginx-deployment
    linkerd.io/workload-ns: default
    pod-template-hash: 858bdd545b
  name: nginx-deployment-858bdd545b-55jpf
  namespace: default
  ownerReferences:
  - apiVersion: apps/v1
    blockOwnerDeletion: true
    controller: true
    kind: ReplicaSet
    name: nginx-deployment-858bdd545b
    uid: 2e618972-aa10-4e35-a7dd-084853673a80
  resourceVersion: "23820"
  uid: 62f1857a-b701-4a19-8996-b5b605ff8488
spec:
  containers:
  - env:
    - name: _pod_name
      valueFrom:
        fieldRef:
          apiVersion: v1
          fieldPath: metadata.name
    - name: _pod_ns
      valueFrom:
        fieldRef:
          apiVersion: v1
          fieldPath: metadata.namespace
    - name: _pod_nodeName
      valueFrom:
        fieldRef:
          apiVersion: v1
          fieldPath: spec.nodeName
    - name: LINKERD2_PROXY_LOG
      value: warn,linkerd=info
    - name: LINKERD2_PROXY_LOG_FORMAT
      value: plain
    - name: LINKERD2_PROXY_DESTINATION_SVC_ADDR
      value: linkerd-dst-headless.linkerd.svc.cluster.local.:8086
    - name: LINKERD2_PROXY_DESTINATION_PROFILE_NETWORKS
      value: 10.0.0.0/8,100.64.0.0/10,172.16.0.0/12,192.168.0.0/16
    - name: LINKERD2_PROXY_POLICY_SVC_ADDR
      value: linkerd-policy.linkerd.svc.cluster.local.:8090
    - name: LINKERD2_PROXY_POLICY_WORKLOAD
      value: $(_pod_ns):$(_pod_name)
    - name: LINKERD2_PROXY_INBOUND_DEFAULT_POLICY
      value: all-unauthenticated
    - name: LINKERD2_PROXY_POLICY_CLUSTER_NETWORKS
      value: 10.0.0.0/8,100.64.0.0/10,172.16.0.0/12,192.168.0.0/16
    - name: LINKERD2_PROXY_INBOUND_CONNECT_TIMEOUT
      value: 100ms
    - name: LINKERD2_PROXY_OUTBOUND_CONNECT_TIMEOUT
      value: 1000ms
    - name: LINKERD2_PROXY_CONTROL_LISTEN_ADDR
      value: 0.0.0.0:4190
    - name: LINKERD2_PROXY_ADMIN_LISTEN_ADDR
      value: 0.0.0.0:4191
    - name: LINKERD2_PROXY_OUTBOUND_LISTEN_ADDR
      value: 127.0.0.1:4140
    - name: LINKERD2_PROXY_INBOUND_LISTEN_ADDR
      value: 0.0.0.0:4143
    - name: LINKERD2_PROXY_INBOUND_IPS
      valueFrom:
        fieldRef:
          apiVersion: v1
          fieldPath: status.podIPs
    - name: LINKERD2_PROXY_INBOUND_PORTS
      value: "80"
    - name: LINKERD2_PROXY_DESTINATION_PROFILE_SUFFIXES
      value: svc.cluster.local.
    - name: LINKERD2_PROXY_INBOUND_ACCEPT_KEEPALIVE
      value: 10000ms
    - name: LINKERD2_PROXY_OUTBOUND_CONNECT_KEEPALIVE
      value: 10000ms
    - name: LINKERD2_PROXY_INBOUND_PORTS_DISABLE_PROTOCOL_DETECTION
      value: 25,587,3306,4444,5432,6379,9300,11211
    - name: LINKERD2_PROXY_DESTINATION_CONTEXT
      value:  
         "ns":"$(_pod_ns)", "nodeName":"$(_pod_nodeName)" 
    - name: _pod_sa
      valueFrom:
        fieldRef:
          apiVersion: v1
          fieldPath: spec.serviceAccountName
    - name: _l5d_ns
      value: linkerd
    - name: _l5d_trustdomain
      value: cluster.local
    - name: LINKERD2_PROXY_IDENTITY_DIR
      value: /var/run/linkerd/identity/end-entity
    - name: LINKERD2_PROXY_IDENTITY_TRUST_ANCHORS
      value:  
        -----BEGIN CERTIFICATE-----
        MIIBiDCCAS6gAwIBAgIBATAKBggqhkjOPQQDAjAcMRowGAYDVQQDExFpZGVudGl0
        eS5saW5rZXJkLjAeFw0yMjExMDUxOTIxMDlaFw0yMzExMDUxOTIxMjlaMBwxGjAY
        BgNVBAMTEWlkZW50aXR5LmxpbmtlcmQuMFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcD
        QgAE8AgxbWWa1qgEgN3ykFAOJ3sw9nSugUk1N5Qfvo6jXX/8/TZUW0ddko/N71+H
        EcKc72kK0tlclj8jDi3pzJ4C0KNhMF8wDgYDVR0PAQH/BAQDAgEGMB0GA1UdJQQW
        MBQGCCsGAQUFBwMBBggrBgEFBQcDAjAPBgNVHRMBAf8EBTADAQH/MB0GA1UdDgQW
        BBThSr0yAj5joW7pj/NZPYcfIIepbzAKBggqhkjOPQQDAgNIADBFAiAomg0TVn6N
        UxhOyzZdg848lAvH0Io9Ra/Ef2hxZGN0LgIhAIKjrsgDUqZA8XHiiciYYicxFnKr
        Tw5yj9gBhVAgYCaB
        -----END CERTIFICATE-----
    - name: LINKERD2_PROXY_IDENTITY_TOKEN_FILE
      value: /var/run/secrets/tokens/linkerd-identity-token
    - name: LINKERD2_PROXY_IDENTITY_SVC_ADDR
      value: linkerd-identity-headless.linkerd.svc.cluster.local.:8080
    - name: LINKERD2_PROXY_IDENTITY_LOCAL_NAME
      value: $(_pod_sa).$(_pod_ns).serviceaccount.identity.linkerd.cluster.local
    - name: LINKERD2_PROXY_IDENTITY_SVC_NAME
      value: linkerd-identity.linkerd.serviceaccount.identity.linkerd.cluster.local
    - name: LINKERD2_PROXY_DESTINATION_SVC_NAME
      value: linkerd-destination.linkerd.serviceaccount.identity.linkerd.cluster.local
    - name: LINKERD2_PROXY_POLICY_SVC_NAME
      value: linkerd-destination.linkerd.serviceaccount.identity.linkerd.cluster.local
    - name: LINKERD2_PROXY_TAP_SVC_NAME
      value: tap.linkerd-viz.serviceaccount.identity.linkerd.cluster.local
    image: cr.l5d.io/linkerd/proxy:stable-2.12.2
    imagePullPolicy: IfNotPresent
    lifecycle:
      postStart:
        exec:
          command:
          - /usr/lib/linkerd/linkerd-await
          - --timeout=2m
    livenessProbe:
      failureThreshold: 3
      httpGet:
        path: /live
        port: 4191
        scheme: HTTP
      initialDelaySeconds: 10
      periodSeconds: 10
      successThreshold: 1
      timeoutSeconds: 1
    name: linkerd-proxy
    ports:
    - containerPort: 4143
      name: linkerd-proxy
      protocol: TCP
    - containerPort: 4191
      name: linkerd-admin
      protocol: TCP
    readinessProbe:
      failureThreshold: 3
      httpGet:
        path: /ready
        port: 4191
        scheme: HTTP
      initialDelaySeconds: 2
      periodSeconds: 10
      successThreshold: 1
      timeoutSeconds: 1
    resources:  
    securityContext:
      allowPrivilegeEscalation: false
      readOnlyRootFilesystem: true
      runAsUser: 2102
    terminationMessagePath: /dev/termination-log
    terminationMessagePolicy: FallbackToLogsOnError
    volumeMounts:
    - mountPath: /var/run/linkerd/identity/end-entity
      name: linkerd-identity-end-entity
    - mountPath: /var/run/secrets/tokens
      name: linkerd-identity-token
    - mountPath: /var/run/secrets/kubernetes.io/serviceaccount
      name: kube-api-access-9zpnn
      readOnly: true
  - image: nginx:latest
    imagePullPolicy: Always
    name: nginx
    ports:
    - containerPort: 80
      protocol: TCP
    resources:  
    terminationMessagePath: /dev/termination-log
    terminationMessagePolicy: File
    volumeMounts:
    - mountPath: /var/run/secrets/kubernetes.io/serviceaccount
      name: kube-api-access-9zpnn
      readOnly: true
  dnsPolicy: ClusterFirst
  enableServiceLinks: true
  initContainers:
  - args:
    - --incoming-proxy-port
    - "4143"
    - --outgoing-proxy-port
    - "4140"
    - --proxy-uid
    - "2102"
    - --inbound-ports-to-ignore
    - 4190,4191,4567,4568
    - --outbound-ports-to-ignore
    - 4567,4568
    image: cr.l5d.io/linkerd/proxy-init:v2.0.0
    imagePullPolicy: IfNotPresent
    name: linkerd-init
    resources:
      limits:
        cpu: 100m
        memory: 20Mi
      requests:
        cpu: 100m
        memory: 20Mi
    securityContext:
      allowPrivilegeEscalation: false
      capabilities:
        add:
        - NET_ADMIN
        - NET_RAW
      privileged: false
      readOnlyRootFilesystem: true
      runAsNonRoot: true
      runAsUser: 65534
    terminationMessagePath: /dev/termination-log
    terminationMessagePolicy: FallbackToLogsOnError
    volumeMounts:
    - mountPath: /run
      name: linkerd-proxy-init-xtables-lock
    - mountPath: /var/run/secrets/kubernetes.io/serviceaccount
      name: kube-api-access-9zpnn
      readOnly: true
  nodeName: k8s-node1
  preemptionPolicy: PreemptLowerPriority
  priority: 0
  restartPolicy: Always
  schedulerName: default-scheduler
  securityContext:  
  serviceAccount: default
  serviceAccountName: default
  terminationGracePeriodSeconds: 30
  tolerations:
  - effect: NoExecute
    key: node.kubernetes.io/not-ready
    operator: Exists
    tolerationSeconds: 300
  - effect: NoExecute
    key: node.kubernetes.io/unreachable
    operator: Exists
    tolerationSeconds: 300
  volumes:
  - name: kube-api-access-9zpnn
    projected:
      defaultMode: 420
      sources:
      - serviceAccountToken:
          expirationSeconds: 3607
          path: token
      - configMap:
          items:
          - key: ca.crt
            path: ca.crt
          name: kube-root-ca.crt
      - downwardAPI:
          items:
          - fieldRef:
              apiVersion: v1
              fieldPath: metadata.namespace
            path: namespace
  - emptyDir:  
    name: linkerd-proxy-init-xtables-lock
  - emptyDir:
      medium: Memory
    name: linkerd-identity-end-entity
  - name: linkerd-identity-token
    projected:
      defaultMode: 420
      sources:
      - serviceAccountToken:
          audience: identity.l5d.io
          expirationSeconds: 86400
          path: linkerd-identity-token
status:
  conditions:
  - lastProbeTime: null
    lastTransitionTime: "2022-11-05T19:44:16Z"
    status: "True"
    type: Initialized
  - lastProbeTime: null
    lastTransitionTime: "2022-11-05T19:44:19Z"
    status: "True"
    type: Ready
  - lastProbeTime: null
    lastTransitionTime: "2022-11-05T19:44:19Z"
    status: "True"
    type: ContainersReady
  - lastProbeTime: null
    lastTransitionTime: "2022-11-05T19:44:15Z"
    status: "True"
    type: PodScheduled
  containerStatuses:
  - containerID: containerd://62028867c48aaa726df48249a27c52cd8820cd33e8e5695ad0d322540924754e
    image: cr.l5d.io/linkerd/proxy:stable-2.12.2
    imageID: cr.l5d.io/linkerd/proxy@sha256:787db5055b2a46a3c4318ef3b632461261f81254c8e47bf4b9b8dab2c42575e4
    lastState:  
    name: linkerd-proxy
    ready: true
    restartCount: 0
    started: true
    state:
      running:
        startedAt: "2022-11-05T19:44:16Z"
  - containerID: containerd://8f8ce663c19360a7b6868ace68a4a5119f0b18cd57ffebcc2d19331274038381
    image: docker.io/library/nginx:latest
    imageID: docker.io/library/nginx@sha256:943c25b4b66b332184d5ba6bb18234273551593016c0e0ae906bab111548239f
    lastState:  
    name: nginx
    ready: true
    restartCount: 0
    started: true
    state:
      running:
        startedAt: "2022-11-05T19:44:19Z"
  hostIP: 192.168.2.216
  initContainerStatuses:
  - containerID: containerd://c0417ea9c8418ab296bf86077e81c5d8be06fe9b87390c138d1c5d7b73cc577c
    image: cr.l5d.io/linkerd/proxy-init:v2.0.0
    imageID: cr.l5d.io/linkerd/proxy-init@sha256:7d5e66b9e176b1ebbdd7f40b6385d1885e82c80a06f4c6af868247bb1dffe262
    lastState:  
    name: linkerd-init
    ready: true
    restartCount: 0
    state:
      terminated:
        containerID: containerd://c0417ea9c8418ab296bf86077e81c5d8be06fe9b87390c138d1c5d7b73cc577c
        exitCode: 0
        finishedAt: "2022-11-05T19:44:16Z"
        reason: Completed
        startedAt: "2022-11-05T19:44:15Z"
  phase: Running
  podIP: 172.16.36.90
  podIPs:
  - ip: 172.16.36.90
  qosClass: Burstable
  startTime: "2022-11-05T19:44:15Z"

$ cat deploy.yaml 
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2
  template:
    metadata:
      labels:
        app: nginx
      annotations:
        linkerd.io/inject: enabled
    spec:
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - containerPort: 80

$ linkerd viz uninstall   kubectl delete -f -
clusterrole.rbac.authorization.k8s.io "linkerd-linkerd-viz-metrics-api" deleted
clusterrole.rbac.authorization.k8s.io "linkerd-linkerd-viz-prometheus" deleted
clusterrole.rbac.authorization.k8s.io "linkerd-linkerd-viz-tap" deleted
clusterrole.rbac.authorization.k8s.io "linkerd-linkerd-viz-tap-admin" deleted
clusterrole.rbac.authorization.k8s.io "linkerd-linkerd-viz-web-api" deleted
clusterrole.rbac.authorization.k8s.io "linkerd-linkerd-viz-web-check" deleted
clusterrole.rbac.authorization.k8s.io "linkerd-tap-injector" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-linkerd-viz-metrics-api" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-linkerd-viz-prometheus" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-linkerd-viz-tap" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-linkerd-viz-tap-auth-delegator" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-linkerd-viz-web-admin" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-linkerd-viz-web-api" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-linkerd-viz-web-check" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-tap-injector" deleted
role.rbac.authorization.k8s.io "web" deleted
rolebinding.rbac.authorization.k8s.io "linkerd-linkerd-viz-tap-auth-reader" deleted
rolebinding.rbac.authorization.k8s.io "web" deleted
apiservice.apiregistration.k8s.io "v1alpha1.tap.linkerd.io" deleted
mutatingwebhookconfiguration.admissionregistration.k8s.io "linkerd-tap-injector-webhook-config" deleted
namespace "linkerd-viz" deleted
authorizationpolicy.policy.linkerd.io "admin" deleted
authorizationpolicy.policy.linkerd.io "metrics-api" deleted
authorizationpolicy.policy.linkerd.io "proxy-admin" deleted
authorizationpolicy.policy.linkerd.io "tap" deleted
authorizationpolicy.policy.linkerd.io "tap-injector" deleted
server.policy.linkerd.io "admin" deleted
server.policy.linkerd.io "metrics-api" deleted
server.policy.linkerd.io "proxy-admin" deleted
server.policy.linkerd.io "tap-api" deleted
server.policy.linkerd.io "tap-injector-webhook" deleted

$ kubectl get deployments
NAME               READY   UP-TO-DATE   AVAILABLE   AGE
nginx-deployment   2/2     2            2           10m

$ kubectl get deployment nginx-deployment -o yaml   linkerd uninject -   kubectl apply -f -

deployment "nginx-deployment" uninjected

deployment.apps/nginx-deployment configured

$ linkerd uninstall   kubectl delete -f -
clusterrole.rbac.authorization.k8s.io "linkerd-heartbeat" deleted
clusterrole.rbac.authorization.k8s.io "linkerd-linkerd-destination" deleted
clusterrole.rbac.authorization.k8s.io "linkerd-linkerd-identity" deleted
clusterrole.rbac.authorization.k8s.io "linkerd-linkerd-proxy-injector" deleted
clusterrole.rbac.authorization.k8s.io "linkerd-policy" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-destination-policy" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-heartbeat" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-linkerd-destination" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-linkerd-identity" deleted
clusterrolebinding.rbac.authorization.k8s.io "linkerd-linkerd-proxy-injector" deleted
role.rbac.authorization.k8s.io "linkerd-heartbeat" deleted
rolebinding.rbac.authorization.k8s.io "linkerd-heartbeat" deleted
customresourcedefinition.apiextensions.k8s.io "authorizationpolicies.policy.linkerd.io" deleted
customresourcedefinition.apiextensions.k8s.io "httproutes.policy.linkerd.io" deleted
customresourcedefinition.apiextensions.k8s.io "meshtlsauthentications.policy.linkerd.io" deleted
customresourcedefinition.apiextensions.k8s.io "networkauthentications.policy.linkerd.io" deleted
customresourcedefinition.apiextensions.k8s.io "serverauthorizations.policy.linkerd.io" deleted
customresourcedefinition.apiextensions.k8s.io "servers.policy.linkerd.io" deleted
customresourcedefinition.apiextensions.k8s.io "serviceprofiles.linkerd.io" deleted
mutatingwebhookconfiguration.admissionregistration.k8s.io "linkerd-proxy-injector-webhook-config" deleted
validatingwebhookconfiguration.admissionregistration.k8s.io "linkerd-policy-validator-webhook-config" deleted
validatingwebhookconfiguration.admissionregistration.k8s.io "linkerd-sp-validator-webhook-config" deleted
namespace "linkerd" deleted

$ kubectl get pods -A
NAMESPACE     NAME                                       READY   STATUS    RESTARTS        AGE
default       nginx-deployment-cd55c47f5-99xf2           1/1     Running   0               82s
default       nginx-deployment-cd55c47f5-tt58t           1/1     Running   0               86s
kube-system   calico-kube-controllers-59697b644f-7fsln   1/1     Running   2 (3h39m ago)   7d1h
kube-system   calico-node-6ptsh                          1/1     Running   2 (3h39m ago)   7d1h
kube-system   calico-node-7x5j8                          1/1     Running   2 (3h39m ago)   7d1h
kube-system   calico-node-qlnf6                          1/1     Running   2 (3h39m ago)   7d1h
kube-system   coredns-565d847f94-79jlw                   1/1     Running   2 (3h39m ago)   7d2h
kube-system   coredns-565d847f94-fqwn4                   1/1     Running   2 (3h39m ago)   7d2h
kube-system   etcd-k8s-master                            1/1     Running   2 (3h39m ago)   7d2h
kube-system   kube-apiserver-k8s-master                  1/1     Running   2 (3h39m ago)   7d2h
kube-system   kube-controller-manager-k8s-master         1/1     Running   2 (3h39m ago)   7d2h
kube-system   kube-proxy-4n9b7                           1/1     Running   2 (3h39m ago)   7d2h
kube-system   kube-proxy-k4rzv                           1/1     Running   2 (3h39m ago)   7d2h
kube-system   kube-proxy-lz2dd                           1/1     Running   2 (3h39m ago)   7d2h
kube-system   kube-scheduler-k8s-master                  1/1     Running   2 (3h39m ago)   7d2h

"And sin, young man, is when you treat people as things. Including yourself. That's what sin is." "It's a lot more complicated than that " "No. It ain't. When people say things are a lot more complicated than that, they means they're getting worried that they won t like the truth. People as things, that's where it starts."

"No, my Uncle Igor thtill workth for him. Been thtruck by lightning three hundred timeth and thtill putth in a full night'th work."

"Ach, hins tak yar scaggie, yer dank yowl callyake!"

• Miguel A. Ruiz Transparent (spanish ambient, March 2020) Transparent by Miguel A. Ruiz
• Arushi Jain My People Have Deep Roots (ambient, drone, atmospheric, indian) Under the Lilac Sky by arushi jain
• K Den - Love Horses (Ambient, builds up, never quite reaching DnB) Brabuhr Q-ih by Various Artists
• Bivouac The Great Escape (drone, spoken word, ambient, psych, November 2021; not on Spotify) bivouac - S/T by bivouac
• Gazelle Twin & NYX - Throne (ambient, choral, dark, drone, January 2022) Deep England by Gazelle Twin & NYX
• Nurse With Wound Transfiguration 3 (Incorporating Opium Cabaret) (March 2022)
• Eluvium Indoor Swimming At The Space Station (ambient, chill, long, loops, euphoric, March 2022) Indoor Swimming At The Space Station by Eluvium
• Hildur Gu nad ttir The Door
• Delia Derbyshire Ziwzih Ziwzih OO-OO-OO (November 2021)
• Afterhere, Berenice Scott, Glenn Gregory - Butterfly (from the Vigil TV series, September 2021)
• Wardruna Andvevarljod (2021)
• Christina Vantzou Dvorjacked (March 2021) Colliding Wind by Concentric Records
• Oranssi Pazuzu Ilmestys (January 2022) Ilmestys by Oranssi Pazuzu
• Coil Tiny Golden Books Tiny Golden Books by Coil
• Gazelle Twin & Trash Generation History History by Gazelle Twin & Trash Generation
• Isambard Khroustaliov A Pre-History of Cybernetics (Freak Zone) (Feb 2022) A Pre-History of Cybernetics by Isambard Khroustaliov
• Boards of Canada Dayvan Cowboy (via Lauren Laverne) (Jun 2022) Dayvan Cowboy by Boards of Canada
• Emeka Ogboh No Countefeit (via Jamz Supernova: trancy, african beats) (Sep 2022) No Countefeit by Emeka Ogboh
• Burial Streetlands (dark ambient) (Oct 2022) Streetlands by Burial
• Raison D'etre - Of Dying Relics (dark industrial/ambient) (Oct 2022) Of Dying Relics by Raison D'etre
• Vanishing 55 N, 5 E (Not on Spotify) 55 N, 5 E by Vanishing
• Ben Salisbury, Geoff Barrow The Alien The Alien by Ben Salisbury, Geoff Barrow
• Coil Strange Birds Strange Birds by Coil

1. Via Stuart Maconie's Freak Zone
2. Via Mary Anne Hobbs
3. Via Lose yourself with
4. Soma FM - Doomed (Halloween Special)

• format the document source for legible reading. Yes, it's the input to the typesetter, and yes, the output of the typesetter needs to be legible. But it's worth making the input easy to read, too. Because
• avoid rebuilding your rendered document too often. It's slow, it takes you out of the activity of writing, and it throws up lots of opportunities to get distracted by some rendering nit that you didn't realise would happen.
• Unless you are very good at manoeuvring around long documents, liberally split them up. I think it's fine to have sections in their own source files.
• Machine-assisted moving around documents is good. If you use (neo)vim, you can tweak exuberant-ctags to generate more useful tags for LaTeX documents than what you get OOTB, including jumping to \label s and the BibTeX source of \cite s. See this stackoverflow post.
• If you use syntax highlighting in your editor, take a long, hard look at what it's drawing attention to. It's not your text, that's for sure. Is it worth having it on? Consider turning it off. Or (yak shaving beware!) tweak it to de-emphasise things, instead of emphasising them. One small example for (neo)vim, to change tokens recognised as being "todo" to match the styling used for comments (which is normally de-emphasised):

  hi def link texTodo Comment
  

• I stick a line of 78 '%' characters between each section and sub-section. This helps to visually break them up and finding them in a scroll-past is quicker.
• I indent as much of the content as I can in each chapter/section/subsection (however deep I go in sections) to tie them to the section they belong to and see at a glance how deep I am in subsections, just like with source code. The exception is environments that I can't due to other tool limitations: I have code excerpts demarked by \begin code /\end code which are executed by Haskell's GHCi interpreter, and the indentation can interfere with Haskell's indentation rules.
• For large documents (like a thesis), I have little helper "standalone" .tex files whose purpose is to let me build just one chapter or section at a time.
• I'm fairly sure I'll settle on a serif font for my final document. But I have found that a sans-serif font is easier on my eyes on-screen. YMMV.

• Don't stop to write a blog post about it.