topic Total Connections Seem lower than they have been previously when adding new volume with NCM in Array Setup and Networking

Total Connections Seem lower than they have been previously when adding new volume with NCM

Wed, 20 Jan 2016 20:56:31 GMT

I have a physical box that is directly connected to the iSCSI network. It has 2 iSCSI NICs. My Nimble has 5 iSCSI +1 Management.

Inside NCM when I connect a new volume, it only connects 8. It seems like there is one on the array side that isn't happy, but I don't have any alerts or other indications to a problem.

My VMware hosts connect and show 10 connections (Each ESXi host has 2 iSCSI connections back to the iSCSI network)

I have another physical box that has 4 iSCSI NICs. The volumes that have been connected for a long time show 20 connections, but the newest one I just added shows 10.

Switch gear is 2 Dell 6024 (not stacked). 4 port port-channel between the 2. All interfaces in the port-channel are up on both switches so I don't suspect issues there.

Where can I investigate this further? Any ideas?

Re: Total Connections Seem lower than they have been previously when adding new volume with NCM

rugby0134 — Fri, 22 Jan 2016 16:10:54 GMT

Connections can be added and removed by NCM based on latency and workload. If you want a static number of connections to can edit the /etc/ncm/ncm.conf file and set the min and max connections.

Re: Total Connections Seem lower than they have been previously when adding new volume with NCM

Mon, 25 Jan 2016 16:57:21 GMT

I'm referring to the NCM on the physical Windows box, not on VMware. The VMware connection count seems fine.

Re: Total Connections Seem lower than they have been previously when adding new volume with NCM

rugby0134 — Mon, 25 Jan 2016 17:05:26 GMT

If your using Nimble connection manager, you can modify the following value for number of connection in Connection Manager:

HKLM\Software\Nimble Storage\Connections

Default is 2, I'd suggest moving that value up slowly as you'll be connecting via the VTIPs on the array with Connection Manager rather then directly to the data IP's. So upping it to 4 should give you one on each connector.

Re: Total Connections Seem lower than they have been previously when adding new volume with NCM

Mon, 25 Jan 2016 17:32:15 GMT

Bingo. That was it, max was set to 8. Thanks, Kevin!