Search Results: "Henrique de Moraes Holschuh"

2 August 2017

Markus Koschany: My Free Software Activities in July 2017

Welcome to Here is my monthly report that covers what I have been doing for Debian. If you re interested in Java, Games and LTS topics, this might be interesting for you. Debian Games Debian Java Debian LTS This was my seventeenth month as a paid contributor and I have been paid to work 23,5 hours on Debian LTS, a project started by Rapha l Hertzog. In that time I did the following: Non-maintainer upload Thanks for reading and see you next time.

15 November 2012

Ian Campbell: Xen Microcode Loading in Wheezy

No sooner had Henrique de Moraes Holschuh announced the availability of improved microcode updating in Wheezy (sadly non-free) than Stephan Seitz pointed out that this support was broken for systems running Xen, which is unfortunate since as Henrique notes the impact of not applying such an update could be pretty much anything. There's a bit of a saga here: a patch has been available for several years which adds Xen support to the kernel's microcode driver in a nicely self contained way. However the Linux maintainers have decided that loading microcode from the kernel is too late and it should be done earlier (e.g. by the bootloader, or some shim between the bootloader and the kernel) in order to be effective and on that basis rejected the Xen patch implementing the existing kernel based scheme. In the meantime Xen has implemented early loading of microcode via an additional multiboot module passed by the bootloader and this was released in Xen 4.2 in September. (so far I've not seen any progress on making any change to the native side but that's by the by). However Wheezy is going to be shipping with Xen 4.1 which doesn't yet have this support in it. So we are basically faced with two choices, either we backport the support from Xen 4.2 or we apply the kernel patch. The downside of backporting rather than taking the kernel patch is that the backport is non-trivial (although not totally unwieldy) while the kernel patch is pretty much entirely self-contained. The other downside of early the early loading scheme in general (for either native or Xen) is the need to update tools (e.g. update-grub) as well as modifying the microcode packaging to put the files somewhere that the bootloader can see them (so /boot). This certainly can't happen for Wheezy at this stage which basically rules out the backport approach. So, the upshot is I've filed Debian bug #693053 and applied the kernel patch to our tree. It's all a bit unsatisfactory but at least microcode loading will work for users running Xen on Wheezy. With any luck for Jessie the native early microcode loading code will have landed as well and the pain of the infrastructure updates can be shared.

13 December 2009

Debian News: Debian is moving sieve to its IANA allocated port

The IANA port allocated for ManageSieve is 4190/tcp, and the old port used by timsieved and other managesieve software in many distros (2000/tcp) is allocated for Cisco SCCP usage, according to the IANA registry.

Starting with the version 4.38 of the Debian netbase package, the sieve service will be moved from port 2000 to port 4190 in the /etc/services file. This affects to those using Debian Squeeze, and Debian Sid. Debian Etch and Debian Lenny users are NOT affected.

Any installs which used the sieve service name instead of a numeric port number will switch to the new port number as soon as the services are restarted/reloaded, and in some cases, immediately after /etc/services is updated.

This will affect Cyrus IMAP. This may also affect other sieve-enabled software such as DoveCot.

In order to avoid downtime problems, mail cluster administrators using Debian are urged to verify their Cyrus (and probably also DoveCot) installs, and take measures to avoid services moving from port 2000/tcp to port 4190/tcp by surprise in either servers or clients.

It is worth noting that:

  1. /etc/services will only be automatically updated if you never made any modifications to it. Otherwise, you will be presented with a prompt by ucf or dpkg asking you about the changes.
  2. You can edit /etc/services and change the sieve port back to 2000 if you want (this is not recommended, though).
  3. You can edit /etc/cyrus.conf and any other relevant config files for your mail/webmail cluster (e.g. on the sieve web frontends) ahead of time to force them all to a static port number.
  4. You can configure cyrus master to listen on *both* ports (2000 and 4190) at the same time, and thus avoid the problem entirely. This also allows for a much more smooth migration from port 2000 to port 4190.

Henrique de Moraes Holschuh