Re: [libvirt] [PATCH] implement BOOT_TIMEOUT
On 04/14/2011 04:32 PM, Eric Blake wrote:
On 04/14/2011 04:21 AM, Alexander Todorov wrote:
> I've come across a situation where one of the guests needs to start
> first (provides a database) and then another guests needs to start
> second (an app server). The reason is that this is a proprietary app
> which is badly written and fails to connect/re-connect to the database
> if it is not online in the first place.
Without more code on the libvirt front, I think you're stuck renaming
the guests to enforce naming order (assuming that libvirt even goes by
sorted name order, as opposed to readdir() order where you have no control).
Of course that does no good if guest A which happens to startup on Host
1 has a prerequisite of guest B which may already be running on Host 2,
or may not be running at all.
So should libvirt try to solve the problem for the special case of all
guests on one host, or defer it to higher level management, which may
know about more than one host? Maybe libvirt could just make space for
the information about dependencies in the domain XML, but not do
anything to try and enforce it (or maybe that could be something
optionally enabled in system config for installations with a single host).