On Fri, Apr 18, 2008 at 04:39:18PM -0500, Mike McGrath wrote:
On Fri, 18 Apr 2008, Kostas Georgiou wrote:
On Fri, Apr 18, 2008 at 03:33:22PM -0500, Mike McGrath wrote:
The only reason we haven't done this already is the inability to detect if the box is already up somewhere (which is something we need already) Consider this scenario:
app1 running on xen1 (which is having high load from koji1 also on xen1)
People complain about the wiki.
We move app1 to a more free box, xen7.
high load causes CRASH
xen1 reboots. Attempts to bring app1 up (already up on xen7)
Two machines try to write to the same disk - DOOM.
What about using gfs (or maybe just nfs from the netapp) to keep the contents of /etc/xen/auto "synced" between hosts? Having /etc/xen/auto as a link to [sharedarea]/auto-xenXX and making sure that the entries there are unique will be a good start for a solution I think.
Network file shares are ill suited for tasks like configuration management IMHO.
I don't disagree, I don't like it either. RedHat magazine had an article[1] recently about xen failover using conga. It might give some ideas even if you prefer not to use gfs (probably a bad idea to have host images in gfs anyway).
Kostas
[1] http://www.redhatmagazine.com/2007/08/23/automated-failover-and-recovery-of-...