> There are three disks in each data centre. Currently I only use the disks > in rza. > > At the moment I'm testing with a two node cluster. The virtual machines are > on SAN disks and I can live migrate from one node to the other one. But > what I have to cover is the disaster. What happens when the fabric in rza > crashes? My virtual maschines are unavailable. What I'm thinking about is a > hardware based > mirroring between the both fabrics and break up the mirror when the > disaster happens or we need to power off the storage for maintenance. But > my problem is that I see duplicate pv id's in this situation. I cannot > mirror based on lvm because it is too slow. Do You want do implement automatic failover or manual? You need hardware based mirroring - I'm sure that Hitachi support it(but it cost come $ for license). The second choice is DRBD[1] with fe. iSCSI or GNBD, but You have SAN which is better. If You need automatic failover, You have to set device-mapper-multipath with Active/Standby configuration where Active is Your rza and Standby Your secondary rzb[2]. In this case You have to set also synchronous replication both side. [1] - http://www.drbd.org/ [2] - http://storagefoo.blogspot.com/2006/08/linux-native-multipathing-device.html Best Regards Maciej Bogucki -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
