Hello, I am wondering if there is anyone on list that is successfully serving virtual machine images (Xen, KVM, VMWare, etc.) over GlusterFS. I am concerned about difficulties the interaction with GlusterFS and large files that are held open for large periods of time (except when the VM is rebooted). My main concern is with replication and failover. Is it currently possible to setup relatively transparent failover of a brick or will the VMs all need to be rebooted to "reopen" their disk images when a brick goes down. The setup we were thinking of going with here is client striping + server side AFR. I don't know whether HA will need to be involved in order to make this happen. Also, for the current self-healing mechanism to work my understanding is that the image (file) will need to be closed and reopened, i.e. the VM will need to be rebooted but this may be fixed with the new healing tools I think are coming in 2.0? Thanks, Alexander
> I am wondering if there is anyone on list that is successfully serving > virtual machine images (Xen, KVM, VMWare, etc.) over GlusterFS. I amI using it with Xen and vserver. With Xen and large disk images it works. Live migration and failover works. Healing is a major problem. It blocks the image for sometime so you have downtime anyway. I have to write a heartbeat ressource to manage the healing before restart the VM. Linux Vserver works to but there are performance issues im working on. It is no problem to "dd" a file to gluster with reasonable speed but in "realtime" vserver is much faster on drbd then on gluster. Maybe I hit a "lot of small files" Problem here or there is a problem with vservers COW mechanism. I use 1.3.12 only. Matthias
Alexander Atticus wrote:> I am wondering if there is anyone on list that is successfully serving > virtual machine images (Xen, KVM, VMWare, etc.) over GlusterFS. I am > concerned about difficulties the interaction with GlusterFS and large > files that are held open for large periods of time (except when the VM > is rebooted).Afaik, VMWare won't recognize a Gluster mountpoint as a valid datastore. This isn't an issue with Gluster specifically, but rather with VMWare generally ; Samba and NFS are the only network filesystems which work in this capacity, with Samba being a relatively new addition at that. -- Daniel Maher <dma+gluster AT witbe DOT net>