On Thu, Dec 23, 2010 at 11:23 AM, Tim Mauerbach <span dir="ltr"><<a href="mailto:tim.mauerbach@googlemail.com">tim.mauerbach@googlemail.com</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
I am thinking about the structure of a new mailserver on top of raid1/lvm/xen.<br><br>Two different approaches come to my mind:<br><br>1. One big LV as DRBD
backing device for the whole guest (os + data).<br>2. One small LV without drbd for the base system + one big LV as DRBD
backing device only for data (maildirs+mariadb).<br><br>Is the maintenance overhead of 2 worth the performance gain?<br></blockquote><div><br></div><div>I'd definitely go with 1, and it has nothing to do with performance. If you put the whole VM on top of DRBD, and then make that a primary/primary (aka active/active) DRBD then you can live-migrate the VM between host and/or use Remus VM-mirroring for VM-HA. I don't see why anyone would ever go with 2 as leaving the OS unreplicated on the small LV exposes you to big potential downtime as you rebuild a new OS for the replicated-data in the event of a failure. Am I misinterpreting what you mean?</div>
<div><br></div><div>-JR</div></div>