JR wrote: >Yea I was out of pocket for a few days, but basically, you end up with 3 DRBD >devices, 1 per VM/service right?
Yes. And every DRBD device on his own LV. Same thing on the second node. >When I said "dual-primary" I was speaking of DRBD only. DRBD in "dual-primary" >aka "active-active" is analogous to a "shared storage"--such as a DAS or SAN >connected to servers via HBAs with the same LUN mapped to both servers--modulo >split-brain considerations as >explained above. That does *not* mean, that both identical vm's are running simultaneously on the two nodes, right ? >The reason you make it active-active on both nodes is because with >Live-Migration the VM does exist simultaneously on both nodes for a brief >period of time as the memory pages/state are >migrated over and both access the block device simultaneously yet in a >synchronized manner through the underlying HyperVisor. Indeed, there is a >mechanism in place for synchronization as your >surmised there must be. Don't I need a cluster aware FS for that short period of time when both are running ? What mechanism for synchronization do you mean ? Can I realise the Live migration with cluster tools, or with KVM tools ? If I use KVM tools, don't they interfere with the HA-Software ? Bernd _______________________________________________ drbd-user mailing list [email protected] http://lists.linbit.com/mailman/listinfo/drbd-user
