Re: [libvirt] Live migration sanity checks

On Wed, Sep 03, 2008 at 01:53:44PM +0100, Daniel P. Berrange wrote: > On Wed, Sep 03, 2008 at 08:43:44AM -0400, Konrad Rzeszutek wrote: > > > amount of host 'setup'. If a guest is using iSCSI as its storage, then > > > there is a step where the host has to login to the iSCSI target and create > > > device nodes for the LUNs before the guest can be run. You don't want > > > every single host to be logged into all your iSCSI targets all the time. > > > > I am interested to know why you think this is a no-no. If you have a > > set of hosts and you want to be able to migrate between all of them and your > > shared storage is iSCSI why would it make a difference whether you had logged in > > or logged in on the migrate on each host? > > In the general case it is a needless scalability bottleneck. If you have 50 > iSCSI targets exported on your iSCSI server, and 1000 hosts in the network,

> So in the context of oVirt the question of iSCSI connectivity may be a > non-issue. In the context of libvirt, we cannot assume this because its > a policy decision of the admin / application using libvirt. Sure. Isn't the code providing a GUID for the iSCSI pool so that before a migrate, the nodes can compare their GUIDs to find a match? And if not, complain so that the admin would create a pool.