[Fedora-xen] Xen and disaster recovery / redundancy / failover

[Andy Burns]

2008/7/3 Jack <xen at tequilasolutions.com>:

> I currently run two servers, one for mail, one for web + db, but will be
> expanding in future so a virtual architecture seems a good idea, especially if I can
> run the VM's on any of the physical machines on the fly as load / failures dictate.

If you want to be able to failover VMs between hosts, you need the
storage for the virtual disks to either be replicated between all
hosts (drbd, cluster filesystem, etc), or to be stored on a external
device (iSCSI, NFS etc) without that each VM depends on the single
server where its disk resides.