I have strange problem. Few days ago I replaced 1 ESXi host in our cluster with new one.
I'm using the same HBA card, the same cables connected to same ports in Brocade switch.
I am using Veeam 8 for backup. Everything works great with virtual machines on this host, but when backup starts, disk latency is jumping up to 700 DAVG/cmd, when KAVG and QAVG are under 20.
We are using EMC VNX. In the cluster I have 2 more hosts with exactly the same configuration and the same HBA model, but the problem is only on this newest one, so it's definitely not the storage problem.
Fiber cables are tested. Zoning was configured correctly when HBA card was in old host.
I am thinking about getting brand new HBA and configure zoning again, but it costs a lot and I don't want to spend much money if the problem is in configuration.
Any advices what should I check?
Or how to find out if this latency is zoning problem?