2015-04-03 07:08 AM
Hello all, I have a simple question about Cluster Mode interconnect links.
In a cluster with 4 node (2 HA Pair) all connected to 2 CN1610 switches, what happen to the SVMs if I lost both the switches at the same time?
2015-04-03 07:20 AM
If would depend on your data paths. As long as the clients were using a LIF that exists on the same node as the SVM's volumes (the optimized path you should be using always anyway), the SVM should continue to serve data. You would lose cluster-wide management of course, as the cluster management LIF would only have connectivity to the node it was running on when the cluster switches failed. Storage Failover should still be in place as well. Hopefully everyone has fully redeundant power sources for their cluster switches, but from what I understand data access should not be affected should you have a dual failure like this.
2015-04-03 08:30 AM
We tested this, within a few mintues of losing both switches the cluster went done, we tested this on 8.2.0, I can't be sure what would happen in newer version. The real question is what do you think the chances are of losing both switches? The MTBF on switches is very high. You can put the switches in two diifferent cabinets to lower this chances of losing both switches.
2015-04-07 11:16 AM
2015-04-07 01:30 PM
In this example, why don't you install a single switch in each datacenter and use long ISL connections as well as the connections from each node? That way even if you lost a whole datacenter, the HA pair in the active datacenter would have a single link to the cluster network still?
2015-04-07 01:56 PM
This is what I initially want to do, but on PartnerEdge configurator, the switch intercconect ISL must be configured with 4 port cabled only with copper cables of 0.5, 2, 3 or 5 meters length.
I suppose for c-dot compliance reasons only.
This mean switches must be in the same datacenter.
Maybe PVR request could be allow other ISL configuration?