Re: Segmentation fault on startup

Helmut Bender <pgsql(at)helmut-bender(dot)de> writes:
> I'm running a nextcloud server in a docker container on an RasPi 4 (only
> SSD, no SD), which uses PostgreSQL 10 as server.

10.what? We're already up to 15 patch releases for that branch.

> Today I had to restart the RasPi. Now the container fails to start with
> a segmentation violation.

Not good --- sounds like you have data corruption. After an OS crash
this is something that's quite possible if you haven't taken the time
to qualify the storage subsystem's honoring of fsync.

It is barely possible that it's a PG bug that we've fixed, so if you
are not on 10.15 then an update would be worth trying. But I don't
have a lot of hope for that.

> I have a dump of the data, but without running server I can't do
> anything with it either...

If it's a reasonably recent dump, you might end up just having to
re-initdb and restore the dump.

If the missing data is very valuable to you, there are people around
who specialize in trying to recover data from corrupted databases
(see "Professional Services" on our website). But it's expensive
and there's no guarantee how much can be recovered.

As with all else computer-related, there's no substitute for a
good backup plan :-(

regards, tom lane