Adventures in home computing

[mdlbear]

... part mumble. Just before leaving for six days of Westercon, I very sensibly put my backup drive in another room and made a second set of backups (just of the important stuff: /home, /local/starport, and /mm/record) on yet another drive that I had lying around. Came back, retrieved the backup drive, and did a full backup. The system hung when I tried to unmount it.

Oops.

Taking this as a Bad Sign, I did an fsck after the reboot, and sure enough the disk was fscked up, though not too badly. From the dates on the inodes in lost+found, I'd say I had a couple of corrupted directories due to a crash back in 2005. Redid the current backups, and all is well for the moment. But I was very glad of the spare backup disk -- things could have been much worse.

But a corrupted directory can potentially cause an arbitrary amount of data to go kablooie, or at least become very hard to recover. My current nefarious plan to back up remotely using encrypted blobs has a similar problem unless there's enough reduncancy in the system to ensure that I never lose all the copies of any one blob. (It's still somewhat safer because blobs -- even directory blobs -- are immutable and so never have to be rewritten. Hmm: log-structured blob store?