Feasibility of Red Hat Cluster Manager and LVM for Cyrus IMAP

[Ken Murchison]

Sebastian Hagedorn wrote:
> 
> Hi,
> 
> we're currently planning a big scale migration of our mail system. At the
> moment we use two different setups for students and for staff, both running
> sendmail and UW IMAP and POP.
> 
> We want to move to one system using sendmail and Cyrus 2.1.x. There will be
> about 50,000 users. The current plan is to use a cluster of altogether four
> Dell servers running Red Hat 7.3. The MTA-Out and some other services will
> be load balanced on two of the machines using LVS aka Piranha.
> 
> The MTA-In / IMAP / POP part will not be load-balanced, but the idea is
> rather to increase its availability. This we plan to achieve by using the
> Red Hat Cluster Manager as Failover Service. The two servers will be
> physically connected to an external RAID box with two SCSI controllers.
> When one of them goes down the other one mounts the required volumes off
> the RAID box and starts the configured services.
> 
> Has anybody on the list ever done something like this?
> 
> Another question I have regards the partitions for the Cyrus mailboxes.
> Using the Linux logical volume manager (LVM) and XFS's xfs_grow command it
> is possible to grow partitions while the machine is running and they are
> mounted.


AFAIK, xfs_grow can only be done on an unmounted filesystem.  I'd also
be surprised if you could add to a logical volume while its mounted.

-- 
Kenneth Murchison     Oceana Matrix Ltd.
Software Engineer     21 Princeton Place
716-662-8973 x26      Orchard Park, NY 14127
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