On Apr 4, 2005 10:34 AM, Phil Brutsche <[EMAIL PROTECTED]> wrote: > Sten Fredriksson wrote: > > Hi, > > > > I know that this has been up before but after searching I found a fix > > that maybe have changed the thought on NFS as back end storage [1] > > [...] > > > If NFS Is a big no no (as it's almost always are by default) how > > would I build a back end that is redundant/fail-over? > > While NFS may work under RHEL, there's still no guarantee that it will > work correctly under other operating systems, or even other Linux > distributions. Therefore I doubt the maintainers will update the FAQ. > > What some people do for fail-over is use some sort of heartbeat > mechanism that will detect when the "master" is unavailable and cause > the "slave" to take over the IP address (if one isn't using the MURDER > aggregator), mount the volumes, etc. > > The volumes would be shared between multible machines using: > > a) a shared SCSI bus > b) fiber channel SAN > c) DRBD (http://www.drbd.org/) > > This will give you active/passive failover. > > While you could theoretically share the volumes between 2 (or more) > computers directly for active/active failover, you run into many of the > same problems as with NFS (mmap not working right over the cluster file > system, etc). It would also require the use of the pre-alpha Cyrus IMAP > 2.3 code.
Would it still be "big no no" if back ends store their mail on NFS mounted storage but not sharing and use some sort of heartbeat (keepalived / heatbeat etc) to take over the ip and mount up the storage. Or is NFS even if not sharing mail storage is not supported and/or recommended at all? DRBD (http://www.drbd.org/) looks interesting. Do anyone of you use it and how does it work for you? // Sten --- Cyrus Home Page: http://asg.web.cmu.edu/cyrus Cyrus Wiki/FAQ: http://cyruswiki.andrew.cmu.edu List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html
