wiki:MaintainingAutodebathenify

Version 1 (modified by jdreed, 10 years ago) (diff)

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autodebathenify is a cron job which runs on the builder account and keeps the OpenAFS modules and modified packages under debathena/third up to date when there are upstream changes. It relies on the following:

  • builder@… has access to a local account named debuildsvn on svn.mit.edu with read access to the athena repository.
  • builder@… has write access to the canonical build area and apt repository in the dev cell.
  • The builder account on the build machine has a copy of the signing private key for the apt repository.

The cron job will silently exit if it detects that it is already running. If it fails for any other reason, it will send mail to source-wash@… and touch a file named autodebathenify.suppress which will prevent it from running again until manual intervention. It is important to get autodebathenify running smoothly or the apt repository will become out of date with respect to third-party packages, which in turn will compromise the user experience.

Even if you don't notice failure mail, it's good to check on the status of autodebathenify from time to time. To do this, get tickets as builder and ssh to linux-build-10 as builder. Run "ls -l logs" to see what's been going on. A logfile with size around 48K indicates that autodebathenify ran normally but didn't find any new work to do. A logfile with size around 60 means that autodebathenify.suppress exists and the cron job has stopped running. A longer logfile indicates that autodebathenify attempted to build and upload a package.

Possible failure cases include:

  • One of the upstream apt repositories timed out during an "apt-get update" of an sbuild chroot. If this happens, you can just remove the autodebathenify.suppress file to get the cron job to start running again.
  • autodebathenify tried to build an upstream version which already exists. If this happens, the build will fail at upload time. If this happens, there is a bug in the part of the debathenify-* script which checks whether our apt repository already has the expected version of the built package.
  • Debian and Ubuntu have .orig files with the same name but different contexts for a particular third-party package. This has only happened once, with bash (which is currently not configured into autodebathenify for that reason). We do not have a general mechanism for resolving such issues at this time.
  • The new upstream version of the package is sufficiently different to cause our modifications to fail to apply, and our debathenify-* script needs to be adapted appropriately.

The cron job is run out of builder's home directory, but its canonical source location is in debathena/scripts/build-server in this repository, should it need to be modified.

After several months of operation, LVM snapshots on the build server will start to become slower and slower, as /etc/lvm/cache/.cache grows in size. Turning off the cache entirely seems to cause schroot to occasionally fail; the current solution is to rm /etc/lvm/cache/.cache every so often.