Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Hi all I need some advice for our setup We have one kvm node with some virtual machines on. The storage is provided by two NAS (black box) via iscsi. One of those NAS is for nightly backups. Let's call that backupNAS and the other one dataNAS. Now I had the idea to duplicate one dataNAS LU in realtime to the backupNAS (Fall back if dataNAS has an error). That's how I came across drbd. The LU is used by samba as a network share. Samba is provided by a VM. The iscsi targets are connected in the kvm host and past on to the VM as a physical device /dev/vdx and /dev/vdy. I created a software raid 1 with both LU, but the io was about 30% less than the io of a single LU. I read that drbd can replicate the data with nearly no loss, so I wanted to give it a try. The idea is to use the dataNAS LU as the primary node and the backupNAS LU as the secondary (protocol A). I understand - the setup is not HA - that usually drbd needs a second (tcp/ip) node to share the data with - but we don't have a second kvm node (this might change in some time). I have read the provided howto: 1) Highly Available Virtualization with KVM, ISCSI & Pacemaker 2) Highly Available ISCSI with DRBD and Pacemaker but both alway use to customizable drbd nodes (I don't know if this is the right wording). As I said, the NAS are black boxes for me, so I cannot/don't want install anything on them. Is there a way to achieve this with my setup? Thanks for all your help. Sebastian