Cyrus questions, lost emails, reconstruct

[Alain Spineux]

On Thu, May 15, 2008 at 2:21 AM, Blake Hudson <blake at ispn.net> wrote:
>
>
> Sounds like bad RAM maybe corrupting the cyrus
> databases... Any other
> indication of file corruption or system
> locking/freezing/rebooting
> (things associated with bad memory) ?
>
> In a PC I'd run memtest86, dunno if that option is
> available to you.
>
> -Blake
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>
>
>
> No signs of bad memory, the server operates off a
> fiber channel RAID and there are no warnings or
> failures with that either.  There are a couple of
> utilities i can try to test the memory, but i will not
> have an answer on that until this weekend.
>
> Why would reconstruct -i work (minus the few
> disappearing emails) and reconstruct -r user/short
> name corrupt the inbox?  I have to assume if the inbox
> didn't get corrupted that the missing emails in
> question would be there.  I have tried to copy emails
> from inbox to a folder in side the usernames folder,
> upon a reconstruct -r those emails are now viewable,
> but the main inbox is still corrupt.
>
> Just a few things I tried if any of this helps.
>
> Thanks again for you help in advance
>
> Derrick
>
>
> I'm honestly not familiar with the "-i" option as my 2.3 systems do not seem
> to have that option and I seem to only run reconstruct when restoring
> backups so I don't use it very often on individual mailboxes. The fact that
> files seem to disappear no mater what, and the problem is reproducible,
> seems to indicate there is some larger problem. I haven't heard of this
> being a wide-spread problem I'm going to assume this is something with your
> config or scenario not common to all Cyrus installations.
>
> One of the tests I've used to burn in new systems and test for file
> corruption is to take a large file (an iso or dd if=/dev/urandom works fine)
> and compute the md5sum. Then copy the file and compute the md5sum on the
> copy. Compare, delete, and repeat via shell script. This could be from one
> drive to another, one partition to another, or just one file to a different
> file.

Nice idea for system that cannot be stopped, but memtest86 available
on all centos, redhat, fedora
installation cd (and probably lot of other distributions) are made for
that and will detect any failure in memory.
Of course memetest86 will ignore any drive failure :-)

>
> Might try something similar to test your system, and it doesn't even require
> a maintenance window...
>
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> Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki
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>



-- 
Alain Spineux
aspineux gmail com
May the sources be with you