Re: Use tar to online backup has an error

* David Steele (david(at)pgmasters(dot)net) wrote:
> It's actually perfectly normal for files to disappear during a
> backup, even when pg_start_backup() is called first (never perform
> file-level backup with calling pg_start_backup()). The database

*without* calling pg_start_backup, you mean. :)

> All of this is reconciled during the replay of WAL after a restore.

... which is why archive_command must be set and the WAL files must be
archived, otherwise PG can't go back and replay those changes.

> Another option is to use purpose-built backup software such as
> pgBackRest or barman, both of which are open source.

+100. Rolling your own backup solution for PG really stinks and is
difficult to get right. Use something which knows about all of the
above, verifies that all the necessary WAL is archived, does all of the
correct fsync's for the WAL files when they're saved, handles failure
gracefully, etc, etc.

Thanks!

Stephen