Re: Seeking datacenter PITR backup suggestions

Gregory Stark wrote:

>> In your scenario, what about using "cp -l" (or "ln") instead?....
>
> Postgres tries to reuse WAL files. Once the archive_command completes it
> believes it is safe to reuse the old file without deleting it. That will do
> nasty things if you've used ln as your archive command.

Um, OK. I won't try that. Thanks. That really could be nasty as I
imagine that it would cause either corruption or failures on the standby
server that might be very hard to track down.

> In theory the only thing that the archive command blocks is the reuse of WAL
> log files....

What happens if PG server crashes during a WAL transfer? Does it still
know the file needs to be transferred or is doing a fast copy to a local
(same machine or machine on local network) from which files are
transferred over a slow-link a safer process?

Also, in the (rare) case that PG needs to be restarted, will the restart
block while waiting for all current log transfers to complete?

Cheers,
Steve