Plans for upgrading Fritz to Debian Squeeze

= Preliminaries =

[[http://www.debian.org/releases/stable/amd64/release-notes/ch-upgrading.en.html|Release Note Information of Upgrading From Lenny]].

== Pre-Install Cleanup Tasks ==

=== Sanitize NSS Configuration ===

 * Synchronize the UIDs of locally created users with their counterparts in AFS
   * `docelic_admin`
   * `rkd_admin`
   * `clinton_admin`
   * `adamc_admin`
   * `shadowfax_admin`
 * Locate and update any files owned by an obsolete UID to the new UID
 * Setup `libnss-afs` (`afs files`)

= Installation environment =

 1. `su` to root, start a `screen` session (preventing partial upgrade issues if the network connection drops)
 1. Open a physical console root login just in case

= Installation Steps =

== Upgrade Kernel and udev ==

 1. Install new kernel image and `openafs-module-dkms`
 1. Install `udev`
 1. Reboot

== Basic Upgrade ==

 1. `apt-get upgrade`
 1. Reboot?

== Full Upgrade ==

 1. `apt-get dist-upgrade`
 1. Reboot?

== Clean Up ==

 1. Make sure the other machines are still sane after losing volume access for a while.

= Caveats =

== pam_unix_session locking all login access ==

This bit us on hopper. ClintonEbadi has confirmed this is '''not''' an issue on `fritz`.

== Locally built packages ==

Todo: someone needs to scan fritz for locally built packages (krb5 and openafs?) and make sure we have an upgrade path for them.

= Service Interruption Mitigation =

== Read Only Volumes on Deleuze ==

Since we have openafs we may as well take advantage of it by adding deleuze's `vicepa` as a site for `user.$USER` volumes. There does not appear to be enough room for `mail.$USER` volumes so we won't worry about those (mail will still be queued and having a read only copy of mail volumes is of dubious value).

=== Preparation ===

A few days before the upgrade:

 * Prevent backup from running (uncomment `exit 0` in `hcoop-backup-wrapper`) before scheduled upgrade date
 * Purge last backup data
 * Purge `db.$USER` volumes
 * Purge `{user,mail}.$USER.d` volumes for members who departed more than (tentatively) 90 ago
 * For all active `user.$USER` volumes: `vos addsite deleuze vicepa user.$USER`

Immediately before upgrading:

 * For all active `user.$USER` volumes: `vos release user.$USER`

=== Clean Up ===

For all user volumes `vos remsite deleuze vicepa user.$USER` to free space for the backup. Alternatively, since the backup will be moved to fritz anyway, leave them in place. There seems to be little benefit to doing so since deleuze does not have much space compared to fritz and we have nothing in place to regularly `vos release` volumes making them effectively useless.