Re: failover with qmail-ldap

Thanks for this idea.
This will be much simpler this way.

__
Lazy


W dniu 2009-04-24, o godz. 17:15, Frank Clements <[email protected]>  
napisał(a):

> Have you checked out DRBD (http://www.drbd.org/)?
>
> I'm running a fully redundant qmail-ldap installation with two  
> incoming MX
> servers and two outbound SMTP servers (load balanced).  Storage  
> server with
> DRBD in the works to provide active/passive storage server failover.
>
> -Frank
>
> -----Original Message-----
> From: Lazy [mailto:[email protected]]
> Sent: Friday, April 17, 2009 5:52 AM
> To: [email protected]
> Subject: failover with qmail-ldap
>
> Hi all
> I'm trying to build a redundant mail system using qmail-ldap.
> The idea is to have 1 primary server and a secondary one which could
> take over in seconds or even work as a secondary MX.
>
> Primary server will be handling pop3 and imap.
>
> Servers would be using same ldap directory.
>
> When a primary server gets an email it delivers it locally and sends a
> copy to the secondary server using qmpc and maybe some hack in
> qmail-queue or qmail-local. Secondary server keeps
> these messages in some kind of log of incoming messages, so they can
> by later reinserted to the queue by some script and qmpc. When
> secondary server receives an email, it adds it to the log of incoming
> messages and delivers it to primary server using similarly patched
> qmpc, or queue.
>
> So we get a file or files with all the incoming messages on secondary
> and real delivery done only on primary server.
>
> When primary server dies all we need to do is reconfigure secondary to
> deliver incoming messages locally, not forward it to now defunct
> primary server, run a script to inject all the messages from the
> incoming messages log on secondary server that now is becoming primary
> and change ip for pop3 imap traffic.
> Of course clients will see all todays email delivered again (pop3
> clients) or marked again as new and undeleted (for imap clients).
>
> Daily there would be a rsync of mail storage from primary to
> secondary, and cleaning incoming messages log on secondary.
> on primary:
> 1. Stop qmail-local
> 2. wait for local deliveries to complete
> 3. make a snapshot of mail storage volume
> 4. signal secondary to clean/rotate incoming messages log
> 5. start qmail-local
> 6. rsync primary mail storage snapshot to secondary
>
>
> What do You think of that ? Could anyone give me any pointers on how
> and where patch qmail-queue or qmail-local, or how to make sure steps
> 1 - 6 get a consistent backup of incomming messages log and mail
> storage snapshot. Mayby it's posiible to do it in some other simpler
> way ?
>