Timesavers: ZFS & BE
I’ve mentioned Boot Environments before. Well, earlier this week BEs and ZFS snapshots saved me a bunch of time. Here’s what happened.
I was in the middle of installing some package (pkg install foo) when my laptop locked up. I had to power cycle it the hard way. When it booted back up, I retried the install, but pkg complained that some state file was corrupted and it didn’t want to do anything. Uh oh. I’ve had similar issue happen to me on Debian with aptitude, so I knew that the hard way of fixing this issue was going to take more time than I’d like to dedicate to it (read: none). Thankfully, I use OpenIndiana which has ZFS and BEs.
- Reboot into a BE from a while ago (openindiana-3). The latest BE (openindiana-4) was created by pkg about a month ago as a clone of openindiana-3 during a major upgrade.
- Figure out which automatic ZFS snapshot I want to revert to. A matter of running zfs list -t all rpool/ROOT/openindiana-4 | tail -5 and picking the latest snapshot which I believe is from before pkg messed it all up. I ended up going an hour back just to make sure.
- Revert the BE. beadm rollback openindiana-4@zfs-auto-snap_hourly-2011-10-25-19h11
- Reboot back into openindiana-4.
After the final reboot, everything worked just fine. (Since the home directories are on a different dataset, they were left untouched.)
Total downtime: 5 minutes
Ease of repair: trivial
Your Turn
Do you have a corrupt package manager war story? Did you just restore from backup? Let me know in a comment.