Re: Backup and bdb-logfile removal

[Quanah Gibson-Mount <quanah@zimbra.com>]

--On Thursday, April 10, 2008 3:26 PM +0200 Peter Mogensen <apm@mutex.dk> 
wrote:

> Gavin Henry wrote:
> > > I can see that I can delete unused log files (db_archive [no options])
> > > from the backup. But when is it safe to remove log files from the
> > > active environment?
> >
> > Let auto-archive do that for you.
>
> Ok.. then I guess, I'm confused by the repeated warnings like:
>
> "To have them removed automatically, place set_flags DB_LOG_AUTOREMOVE
> directive in DB_CONFIG. Note that if the log files are removed
> automatically, recovery after a catastrophic failure is likely to be
> impossible."
>
> and:
>
> "Automatic log file removal is likely to make catastrophic recovery
> impossible."
>
> How to remove log files without making catastropic recovery impossible ?

You can't.  That's why you slapcat periodically so you have an alternative. 
Not that I personally have ever hit a catastrophic event in the years I've 
been using OpenLDAP where the log files would have helped in any way. 
I.e., disk failure? -- logs are useless if they were on the disk that 
failed.  And in that case, I just slapcat a different replica and slapadd 
it onto the server with the failed disk once it has been replaced.  I.e., I 
find having replicas a much more effective disaster recovery mechanism than 
log files that are susceptible to other problems.

--Quanah


--

Quanah Gibson-Mount
Principal Software Engineer
Zimbra, Inc
--------------------
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