On Thu, Mar 01, 2018 at 10:59:15AM +0100, Fabian Grünbichler wrote: > this is problematic because it potentially hides bugs in our application > logic, with currently no benefit. > > with exclusive-locks disabled, mapping on multiple hosts is possible, > but mounting the same image is not (e.g., when attempting to mount, all > but the first successful node will fail). > > with exclusive-locks enabled, mapping and accessing/mounting is > sometimes possible (it seems a bit racy?), but since ext4 is not a > cluster FS, this will cause undesired behaviour / inconsistencies / > corruption. > > OTOH, with exclusive-locks enabled we would have the option of exclusive > mapping - if we find a way to make this work with Qemu live-migration it > might solve all of our problems > > TL;DR: I think we should postpone this pending further investigations > into potential pros and cons > I did some testing on this topic. Qemu dies when live migrating, as rbd can not get the lock on the new destination. A offline migration is possible.
I guess, if we want to use it, then either we get qemu to work differntly on migration or only allow offline migration when exclusive mapping is requested. I am up for discussion. _______________________________________________ pve-devel mailing list [email protected] https://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
