As a quick reply I've attached the configs that I use for both hosts
and strace output for synctest run on B switched to master. Hopefully
this will either demonstrate that the configuration is pretty much
okay, or perhaps give you an idea of where I got the replication setup
wrong.
Meanwhile, I'll try to make those small adjustments you've mentioned
and write back as soon as I'm done.
On Mon, Jul 11, 2011 at 3:47 PM, Bron Gondwana <brong@xxxxxxxxxxx> wrote:
> On Mon, Jul 11, 2011 at 11:40:25AM +0300, Ivan Lezhnjov Jr. wrote:
>> On Sun, Jul 10, 2011 at 11:07 AM, Bron Gondwana <brong@xxxxxxxxxxx> wrote:
>> > I would love to replace monitorsync with better logic in sync_client
>> > itself, but have not yet got to it!
>>
>> So, what does "monitorsync" essentially do with those log files?
>
> Runs sync_client -r -f $file on each file it finds that doesn't have
> a corresponding sync_client process with the same PID actually alive
> (it checks the ps output) - and if the sync_client run succeeds it
> will delete the file, otherwise it emails us about the error and tries
> again in next run (from cron every 10 minutes).
>
>> Jul 11 11:21:14 imapsite-master syncserver[14019]: SSL_accept() timed
>> out -> fail
>> Jul 11 11:21:14 imapsite-master syncserver[14019]: STARTTLS failed:
>> imapsite-replica [10.10.0.188]
>
> Sounds like broken authentication.
>
>> ============================== B switched to master
>>
>> Jul 11 11:33:45 imapsite-replica sync_client[29199]: couldn't
>> authenticate to backend server: no mechanism available
>> Jul 11 11:33:45 imapsite-replica sync_client[29479]: couldn't
>> authenticate to backend server: no mechanism available
>
> And that's definitely broken authentication or different
> configurations.
>
>> > Yeah, of course. You're doing it wrong[tm]. In theory the sync system
>> > can recover from an accidental split brain like this, but it's not
>> > ideal.
>>
>> I'd be happy to learn what I'm doing exactly wrong :)
>
> Changing stuff under the cyrus instances by rsyncing stuff around.
> And it looks like not having the same authentication details or
> configs at each end (modulo the bits that actually start and stop
> the sync_client).
>
> The only difference between our master and replica configs these days
> is that sync_client only gets started on the master. Actually, we
> don't start it from cyrus.conf any more, we bring up the master first,
> and then run sync_client from the init script after the master is
> fully running.
>
>> > > Replication doesn't work now. The question is can it work after doing
>> > > this?
>> >
>> > You've got your rsynced spool and meta out of sync. You will need to run
>> > a full reconstruct -G to fix this, which will replace the incorrect metadata
>> > with what's now in the spool.
>>
>> Thank for the tip. Good to know that ;)
>
> Reconstruct is pretty good. It can deal with most situations where
> cyrus is confused. If you find any where it doesn't, file a bug and
> I'll get it fixed!
>
>> > > So, that's all I have to say perhaps. I would really appreciate any help
>> > > with this. This seems like a basic, trivial scenario to me but I just
>> > > can't seem to get cyrus-imap working right.
>> >
>> > It's not as trivial as it should be yet - and you can mess yourself up
>> > particularly if you go rsyncing stuff between machines! If you have one
>> > host which is "correct" (host B in this case) I recommend that you do a
>> > full reconstruct -r -G on it, and then discard the replica and restart
>> > replication from scratch.
>>
>> I've also just tried to apply these tips. Namely, when B switched to
>> master failed to push changes to A switched to replica I did the
>> following:
>> - stopping the service and then "discarding replica" by removing
>> /var/{lib/imap,spool/imap}
>> - restarting the service with replica role configuration (which is
>> correct by the way)
>>
>> Anything else I could try or check?
>>
>> PS: sorry for direct message to your inbox Bron :)
>
> No worries - though I should warn you that I'm going on holiday for a
> couple of weeks starting tomorrow, so answers may not always be prompt.
>
> Bron.
>
Attachment:
replica-strace-synctest
Description: Binary data
Attachment:
replica-cyrus.conf
Description: Binary data
Attachment:
replica-imapd.conf
Description: Binary data
Attachment:
master-cyrus.conf
Description: Binary data
Attachment:
master-imapd.conf
Description: Binary data
---- Cyrus Home Page: http://www.cyrusimap.org/ List Archives/Info: http://lists.andrew.cmu.edu/pipermail/info-cyrus/
