synchronization/backup mx

[Torsten Schlabach]

 > The config you would need is to use drbd to mirror the data
 > directories

Is this officially supported / endorsed?

I learned that Cyrus IMAPd (for whatever reason) is quite picky on 
filesystems. From the FAQ:

--- SNIP ---

# Using NFS We don't recommend it. If you want to do it, it may possibly 
work but you may also lose your email or have corrupted cyrus.* files. 
You can look at the mailing list archives for more information.
# Using AFS/Coda We don't recommend it. It's even less likely to work 
than NFS. If you want to do it, it may possibly work but you may also 
lose your email or have corrupted cyrus.* files. CMU's previous e-mail 
system, AMS, leveraged AFS extensively for storage (and transit) 
purposes. For various reasons it didn't scale particularly well and led 
to CMU's interest in IMAP.

Cyrus was designed to use a local filesystem with Unix semantics and a 
working mmap()/write() combination. AFS doesn't provide these semantics 
so won't work correctly.

--- SNIP ----

The concept of mirroring the BerkeleyDB database files on a filesystem 
level does not sound that reliable to me. I might be wrong ...

Regards,
Torsten

Jack Stone schrieb:
>>you are searching for heartbeat and drbd
>>
>>>But this will "just" provide the HA filesystem, won't it?
>>>
>>>Isn't there a technology available in Cyrus IMAPd which will replicate
>>>changes to a mailbox to two different servers?
>>>
> 
> 
> 
> Firstly, hello to the list.
> 
> drbd is a file system replication program. However heartbeats will allow
> for a redundant imapd as it can start a new server if the first one dies.
> 
> The config you would need is to use drbd to mirror the data directories
> so that the mail was on both servers and then use heartbeats to detect
> if imapd had died. It could then start a new server automatically.
> 
> Regards,
> 
> Jack Stone
> 
> 
> ----
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