Today, Spain remembers the beginning of the end.
During the evening of the 17th of July and morning of the 18th, a group of
generals of the Spanish regular army raised against the democratically elected
left-wing government of the Republic. History says that the murdering of
Calvo-Sotelo, a right-wing leader, was what finally provoked the conflict.
It was no secret that the same right-wing and some elements in the army had
been conspiring for weeks about an uprise. The only question was when,
but the government was fooled by general Mola and didn't take really effective
measures to prevent it.

Warning from sanitary authorities against venereal diseases
Mola and Sanjurjo planned to start taking over official buildings and army
quarters and quickly seize control of the major cities. During the first hours
of their rebelion, they managed to take over most of the southern regions in
Andalusia, Extremadura and parts of the Northwest, plus most of the islands
and the Moroccan protectorate area. Meanwhile, the Republic did not manage to
react quickly due to the weakness of the government, and in the first days
of the crisis, the government changed a few times. Finally, the Republican
parties decided that to defend the state they should give arms to the unions,
and soon after many militia groups were getting organised in the cities, and
columns sent off to liberate other towns.

Solidarity of Catalunya to the Basque front
The insurrection was suffocated in Barcelona after some heavy fighting
against the military in the Montju c castle; the Anarchists of the
CNT grew strong
in Catalunya and Arag n, and offered good resistance in those fronts.
After the first days of the coupe d'etat, it was clear neither the
legitimate government or the rebels calculated how things would go after the
first days. The government was confident in being able to end the rebelion
as they did four years before; the fascists thought they would have quickly
brought down the government with a successful coup. But after the first week,
the country was divided in two halves, and both sides of the conflict were
keen on fighting, due to the big social fracture during the last months of the
government.
The Republic asked for help to the League of Nations, but the
United Kingdom and France decided not to intervene, scared about the conflict
trespassing the Spanish borders and becoming another bloody war in European
fields. The only official external aid came from the USSR and the
International Brigades,
formed by volunteers of more than 50 nations. Some well-known personalities
like Ernest Hemingway or George Orwell came to aid as well. Orwell wrote about
his life-changing experience in a Barcelona immerse in the social revolution,
where he joined the anti-stalinist socialist party POUM. Badly wounded in the
neck, he left the front and went back to Barcelona, and witnessed the assault
of the Telef nica by the communists against the anarchists, during
the fets de maig, after which the POUM was declared illegal. Orwell
captured his experiences in the frontline and Barcelona in his book
Homage to Catalonia.

To defend Madrid is to defend Catalunya
Franco and Mola, aided by the Northafrican troops and soon after by their
fascist allies of Italy and Germany, didn't have big problems seizing
the Basque Country and Asturies in the North, but not before making the town of
Gernika disappear
below the nazi
Condor Legion bombing,
in what would be a test for the massive aereal bombings of Word War II.
The battle for Madrid was fierce, and the city wasn't occupied until the
very last days of the war. The long defence of the capital made was
immortalised in the famous phrase No pasar n.

Madrid's No pasar n
During the war, anarchist groups controlling fields and towns in Arag n and
Catalunya managed to bring a Social Revolution to the area. The people
collectivised the land and industries, administered by local assemblies. This
experience is regarded as the time when Libertarian Communism has been
successful. The experience ended dramatically when the anarchists were
treasoned and blocked by the communists, and eventually defeated by Franco at
the front.

Each bullet for a target
After the first and a half years, the fronts had stabilised in Madrid and
the East of Andalusia, until early in 1939, Barcelona fell in Franco's hands,
after the bloody Batalla de l'Ebre, being followed by Girona and the
rest of Catalunya. The fate of the democratic state was clear. Two months
later, Madrid fell and Val ncia and the small area still under Republican
control surrended.

Robert Capa's Muerte de un miliciano
Franco declared a totalitarian regime to, according to the fascists,
reconcile the two Spains. In the first five years of the regime, up to
100.000 were executed in the franquist repression, including the Catalan
president, Llu s Companys and many intellectuals. The dictatorship continued
executing people until two months before Franco's death, 36 years later.
Hundreds of thousands also had to exile in M xico, France and other
destinations, leaving Spain in ashes, road gutters full of scattered bodies
and the population facing famine. The cultural elite left the country, making
the state's clock go back at least a decade. Their reconciliation really
meant humiliation and repression. Many people were also murdered during the
war behind republican and rebel lines, but the genocide of the aftermath had
was unmatchable.

The Republic promoted education among the troups
It is a bit late to restore the dignity of the victims, but not
too late. Some associations have been fighting since the end of
Franco's regime to get some kind of public recognition for their suffering,
for their priceless fight for the legal and democratically elected Republic,
for the people who didn't make it.

Excellent anarchist poster rejecting the politisation
of children by any of the three loyal groups
Other people reject these efforts banning them of "revisionism". Not too
surprisingly, these are the sons or grandsons of the people who won the war.
The current government is about to pass a Historic Memory law which aims to
give recognition to all these people who gave their lives for an ideal and
freedom. Unfortunately, due to pressures from the right, it is probable that
the text will be ammended to make it more acceptable by them. I fear it will
end up not pleasing the victims at all.
I have a passion for Spanish Civil War related matters, and in the last
years I tried to use any opportunity to listen to my Catalan grandmother talk
about war affairs in Barcelona, and my grandfather, from a town in the middle
of the Republican side of the Teruel front, but born in a very catholic family,
about how the war went on in Vall and the nearby mountains.

From the defensive No pasar n to the encouraging Pasaremos!
I know my grandfather only told me the less compromising stories, like how
he was sent to dig refuges until he was 16 and apt to fight in the Front, or
how he was put in charge of hiding the church's valuable relics in a few
barns. He never told me about how life was after the war in the small town.
It is dramatic to see that all the people who were old enough to have a sense
of what was going on at the time are so old that these unvaluable memories and
stories will be mostly gone in ten years.
(Most of the pictures are taken from the
Sociedad Ben fica de Historiadores Aficionados y Creadores'
website, which has a huge documented catalog)
path_grouping_policy multibus
path_checker tur
failback immediate
no_path_retry 60
path_selector "round-robin 0"
With SMTP you connect to a server and send two things: envelope and message. The envelope looks like this:
- MTA
- Mail Transport Agent
- MUA
- Mail User Agent
- MDA
- Mail Delivery Agent
- SMTP
- Simple Mail Transfer Protocol
- MX
- Mail eXchange
- POP
- Post Office Protocol
- IMAP
- Internet Message Access Protocol
MAIL FROM: <enrico@enricozini.org> RCPT TO: <rms@fsf.org> RCPT TO: <linus@linux.org>The message looks like this:
From: <enrico@enricozini.org> To: <rms@fsf.org> Cc: <linus@linux.org> Message-ID: <1234567@enricozini.org> Subject: Test mail Hi Richard, this is a test mail. I'm also writing Linus to show how to send to more people. Cheers, EnricoThere is no authentication. There is no encryption. Two usual types of access control:
The DNS is used to find the SMTP server to use to send a message:
- Outbound e-mail is normally only accepted from an internal network
- Inbound e-mail is normally accepted from anywhere
$ host -t MX yahoo.com yahoo.com MX 10 smtp1.yahoo.com yahoo.com MX 20 smtp2.yahoo.com yahoo.com MX 20 smtp3.yahoo.comThe process of sending an E-Mail:
Example of problems with mail handling:
Enrico writes an E-Mail:
From: Enrico Zini <enrico@enricozini.org> To: Richard Stallman <rms@fsf.org> Subject: Hello from Addis Hi Richard, Addis is a wonderful city, even if it rains a lot. Bye, EnricoEnrico's MUA connects to the SMTP server (for example, port 25 of smtp.aau.edu.et):
HELO enricozini.org 200 OK Hello enricozini.org MAIL FROM: <enrico@enricozini.org> 200 OK Mail from enrico@enricozini.org RCPT TO: <rms@fsf.org>Here, the SMTP server performs relay control: "do we relay mail to rms@fsf.org?":A target address could be refused:
- Outbound e-mail is normally only accepted from an internal network
- Inbound e-mail is normally accepted from anywhere
413 ERR I don't relay for rms@fsf.orgIn this case, the destination is not local but the recipient is accepted because I'm inside the local network:200 OK Destination rms@fsf.org DATA 200 OK Please send message body From: Enrico Zini <enrico@enricozini.org> To: Richard Stallman <rms@fsf.org> Subject: Hello from Addis Date: Mon, 17 Jul 2006 09:49:45 +0300 Message-ID: <124372643@enricozini.org> Hi Richard, Addis is a wonderful city, even if it rains a lot. Bye, Enrico . 200 OK Message accepted QUIT 200 OK Bye.The SMTP server needs to find out where to send the message, using the DNS:
$ host -t MX fsf.org fsf.org MX 10 mail.fsf.org fsf.org MX 20 mail.gnu.orgSo the SMTP server tries the first one and connects to port 25 of mail.fsf.org:
HELO smtp.aau.edu.et 200 OK Hello smtp.aau.edu.et MAIL FROM: <enrico@enricozini.org> 200 OK Mail from enrico@enricozini.org RCPT TO: <rms@fsf.org>The destination is accepted because it's for a local user:200 OK Destination rms@fsf.org DATA 200 OK Please send message body From: Enrico Zini <enrico@enricozini.org> To: Richard Stallman <rms@fsf.org> Subject: Hello from Addis Date: Mon, 17 Jul 2006 09:49:45 +0300 Message-ID: <124372643@enricozini.org> Received: by mail.aau.edu.et on Mon, 17 Jul 2006 09:55:53 +0300 from 10.4.15.158 Hi Richard, Addis is a wonderful city, even if it rains a lot. Bye, Enrico . 200 OK Message accepted QUIT 200 OK Bye.Now, mail.fsf.org will invoke a MDA to write the mail in Richard Stallman's mailbox.
RFC-822 is the original standard for E-mail. RFCs are standard Internet documents. Have a look at RFC documents released the 1st of April.
- Accepting inbound connections:
- Malicious input:
- logic errors
- buffer overflows
- DoS (Denial Of Service) attacks
- Connection floods
- Performing outbound connections:
- Programming errors:
- Flooding of connections
- Performing routing:
- Unauthorised relays
- Mail loops
- Writing to the local hard drive:
- Filling up the hard drive
- Writing to the wrong files
- Writing to the local hard drive as root:
- In case of error or attack, any file in the system can potentially be compromised
To test a mail server:
- Mail name: aau.edu.et (name used to publicly identify the mail server)
- Smarthost name: smtp.telecom.net.et (SMTP server that will relay our e-mail)
$ telnet localhost 25 HELO me MAIL FROM: <a@b.c> RCPT TO: <mail@of.a.local.user> DATA hi . QUITBy default, you find locally delivered mail in /var/mail/username. Postfix configuration files:
To rewrite addresses:
- /etc/postfix/master.cf
- configures how all the postfix components run together (man 5 master)
- /etc/postfix/main.cf
- Main postfix configuration (man 5 postconf)
(see file:///usr/share/doc/postfix/html/ADDRESS_REWRITING_README.html) Manipulating the message queue:
In /etc/postfix/main.cf:
canonical_maps = hash:/etc/postfix/canonicalThen in /etc/postfix/canonical you can add the rewrite rules, like:
enrico enrico@enricozini.orgWhen /etc/postfix/canonical is modified you need to regenerate the index:
sudo postmap canonical(same is when you change the alias file: sudo postalias /etc/aliases)
mailq - List the mail queue.Different mail queues in postfix:Example:postqueue - Postfix queue controlmailqExamples:postsuper - Postfix superintendent# Like mailq postqueue -p # Tries to send every message in the queue postqueue -f # Tries to send every message in the queue for that site postqueue -s siteExamples:# Deletes one message sudo postsuper -d 7C4D2EC0F5D # Deletes all messages held in the queue for later delivery sudo postsuper -d ALL deferred
Mail logs are in:
- incoming
- mail who just entered the system
- active
- mail to be delivered
- deferred
- mail to be delivered later because there were problems
- hold
- mail that should not be delivered until released from hold
/var/log/mail.log /var/log/mail.err /var/log/mail.info /var/log/mail.warn
Alternate MDA: procmail: allows to filter mail automatically into different folders. Mail forwarding with ~/.forward: allows to redirect mail to a different address: just put the address you want to send to in the file ~/.forward.
- mbox: single file, mail separated by "From " lines
- maildir: one directory per folder, one file per mail
- mh: similar to maildir, but not really used
apt-get install dovecotConfiguration is in:
/etc/dovecot/dovecot.confThe main thing that is needed is to enable the mail protocols you want:
protocols = imaps
apt-get install munin munin-nodeExample: http://munin.ping.uio.no To compute more statistics:
Monitor system logs: logcheck:
- anteater
- isoqlog
- mailgraph
- sends you mail with abnormal log lines
- It's important to customize what is normal and you do it with regular expressions
spamassassin - Spam filter Spam scanning:
- Postfix gives the mail to clamav that scans it and gives it back if it's clean.
- Strategies for infected mail:
- silently delete it
- refuse the mail and send a notification to the sender
- refuse the mail and send a notification to the receiver
- quarantine the e-mail
- refuse delivery with a SMTP error
- deliver with an extra header that says that it's a virus
- Postfix gives the mail to spamd that scans it and gives it back with some spam information.
- Strategies for spam mail:
- silently delete it
- refuse the mail and send a notification to the sender
- refuse the mail and send a notification to the receiver
- quarantine the e-mail
- refuse delivery with a SMTP error
- deliver with an extra header that says that it's spam
- New techniques:
- greylisting: when you receive a mail from a host you've never seen before, refuse it with a temporary error, and accept it the second time (after some time delay). Spammers normally don't retry, and implementing retry would increase their cost of sending e-mail.
- crossassassin: if more than some amount of your users receive a mail with the same message ID, throw it away. Sending mails with different headers would increase the cost of sending e-mail.
- man man shows all the sections of the manpages
- man 5 postconf shows the postconf manpage in the "configuration file" section
- Normally manpages are referred as manpage(section) (e.g. postconf(5) )
apt-get install samba samba-doc smbclientTo get the Samba Web Administration Tool:
apt-get install swat netkit-inetdThe configuration is in /etc/samba:
One could use swat at http://localhost:901/ but it does not work easily on Ubuntu. To see what is shared:
- One [global] section with the general settings
- One section per share
smbclient -L localhostTo access a share:
smbclient //localhost/name-of-the-shareTo add a new user:
sudo smbpasswd -a usernameTo change the password of a user:
sudo smbpasswd usernameTo test accessing a share as a user:
smbclient //localhost/web -U yaredDocumentation:
man smb.confTo force the user or group used to access a share:
force user = enrico force group = www-dataTo set the unix permissions for every created file:
# For files create mask = 0664 # For directories directory mask = 0775Example share configuration for a webspace:
mkdir /var/www/public chgrp www-data /var/www/public chmod 0775 /var/www/publicThen, in /etc/samba/smb.conf:
[web] comment = Webspace path = /var/www writable = yes public = no force group = www-data create mask = 0664 directory mask = 0775Example share configuration for a read only directory where only a limited group of people can write:
[documents] comment = Documents path = /home/enrico/Desktop/documents force user = enrico public = yes writable = no write list = enrico, yared
apt-get install cupsysConfiguration:
Example IPP URIs:
On the web (not enabled in Ubuntu):
http://localhost:631/On the desktop:
System/Administration/Printing
ipp://server[:port]/printers/queue http://server:631/printers/queue ipp://server[:port]/...For example:
ipp://server/printers/laserjet"This printer uri scheme can be used to contact local or remote print services to address a particular queue on the named host in the uri. The "ipp" uri scheme is specified in the Internet Print Protocol specifications and is actually much more free form that listed above. All Solaris and CUPS based print queues will be accessed using the formats listed above. Access to print queues on other IPP based print servers requires use of the server supported ipp uri format. Generally, it will be one of the formats listed above."
apt-get install ldap-utils slapdThe configuration is in /etc/ldap. To access a ldap server:
apt-get install gqVarious LDAP HOWTOs:
- http://bachue.com/svnwiki/ldap-intro
- http://minkirri.apana.org.au/~abo/projects/ldap-auth/LdapAuthentication.txt
- http://www.unav.es/cti/ldap-smb/ldap-smb-3-howto.html
- http://www.mami.net/univr/tng-ldap/howto/
- http://www.ofb.net/~jheiss/krbldap/howto.html
- http://bachue.com/svnwiki/linux%20ldap%20howto
Grub trick to have a memory checker:
- arrows
- move around
- enter
- enters a section
- l
- goes back
- u
- goes up one node
- q
- quit
- /
- search
apt-get install memtest86+
Add this to /boot/grub/menu.lst:
title Memory test root (hd0,5) kernel /boot/memtest86+.bin
man iptables # Only allow in input the network packets # that are going to the web server iptables -P INPUT DROP iptables -A INPUT --protocol tcp --destination port 80 -j ACCEPT # To reset the input chain as the default iptables -F INPUT iptables -P INPUT ACCEPTSome links:
- http://www.linuxguruz.com/iptables/howto/iptables-HOWTO.html
- NAT = Network Address Translation http://www.netfilter.org/documentation/HOWTO/NAT-HOWTO.html
apt-get install squidThe configuration is in /etc/squid/squid.conf. To allow the local network to use the proxy:
# Add this before "http_access deny all" acl our_networks src 10.4.15.0/24 http_access allow our_networksTo use a parent proxy:
cache_peer proxy.aau.edu.et parent 8080 0 proxy-only no-queryPay attention because /var/spool/squid will grow as the cache is used. The maximum cache size is set in the directive cache_dir. Information about squid access control is at http://www.squid-cache.org/Doc/FAQ/FAQ-10.html To check that the configuration has no syntactic errors: squid -k parse. To match urls:
acl forbiddensites url_regex [-i] regexpFor info about regular expressions:
man regexExample filtering by regular expression:
acl skype url_regex -i [^A-Za-z]skype[^A-Za-z] http_access deny skypeTransparent proxy setup: http://www.tldp.org/HOWTO/TransparentProxy.html
- swat does not run on Ubuntu because Ubuntu does not have inetd
- swat does not allow root login on Ubuntu because root does not have a password
- smbpasswd -a does not seem to update the timestamp of /var/lib/samba/passwd.tdb
- cups web admin does not work on Ubuntu
- LDAP is still not so intuitive to set up
% cd /usr/share/X11/xkb/symbols % cp us mykeymap % vi mykeymapSo far it's simple. Delete everything but keep the
xkb_symbols "basic" part. The format is quite simple, so I won't explain it. I decided to use the right alt key to map several characters I want to use. For this, you have to add include "level3(ralt_switch)" after just before the last bracket.
You can now add other characteres, for example I changed:
key <AB03> [ c, C ] ;to
key <AB03> [ c, C, copyright, registered ] ;So I can type the copyright symbole ( ) by pressing Alt right and c, and the registered symbol ( ) by pressing Alt right, shift and c. The characters name are located in the
/usr/include/X11/keysymdef.h file.
You can change your keymap with setxkbmap mykeymap and to change it definitely, just edit your /etc/X11/xorg.conf.
sysrqd 4094/tcp sysrq daemonI will release a new version today using these ports.
sysrqd 4094/udp sysrq daemon
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