On Sun, Feb 24, 2013 at 12:52:53PM +0100, Gandalf Corvotempesta wrote: > Recap: 4 phisical nodes, each node will host at least 10 VM plus 1 gluster VM > Each VM should boot from the gluster VM By "boot from" I guess you mean that the VM's root device, e.g. hda/vda, will be a disk image file stored on the gluster filesystem? > Do you have any advice on this configuration? Yes: test it carefully to ensure it does what you want. * In my experience, write performance of KVM -> FUSE mount -> gluster is very poor (I was getting about 6MB/s). In your case you have another layer of KVM in this too. * Test carefully all the various failure scenarios, e.g. halting and restarting the gluster VMs, rebooting the whole server, pulling the power out of the whole server and restarting it. Better to learn the failure scenarios here than when in production, because Gluster has precious little documentation on how to cope with them. If the *only* thing you need to do is provide backing storage for VMs, then there are other solutions which might suit you better - you could look at Ganeti and Sheepdog. Ganeti uses LVM to create storage volumes for each VM and then creates DRBD instances on top of them to synchronise replicas between hosts. It provides a full VM cluster manager too, so the command line lets you manage all your VMs from one point. Sheepdog provides a virtual block-storage layer for KVM, where chunks of each volume are distributed and replicated between hosts. However, neither provides a general-purpose shared filesystem as Gluster does. Regards, Brian.
