Problem with vSphere Standard Switch configuration

[LAHCincy]

Have a Datacenter for our test vm's.

ESXi-5.1, 2 hosts.

Noticed that the vm's migrated to one of the 2 hosts have been having issues with losing network connectivity (happens randomly).

Also noticed that new vm's built on this same host cannot connect to the network until migrated to the other host.

Discovered today that the vSphere Standard Switch configuration is slightly different for each host.

We have 3 vSwitches configured for each host:

vSwitch0 is used for vMotion and the Management Network

vSwitch1 is used for iSCI network

vSwitch2 is used for the VM Network

The host in which we're not seeing any connectivity issues with the vm's has:

vSwitch1 (iSCSI1 and iSCSI2) - configured to use vmnic1 and vmnic2

vSwitch2 (VM Network) - configured to use vmnic3 and vmnic5

The host in which we are seeing connectivity issues with the vm's has:

vSwitch1 (iSCSI1 and iSCSI2) - configured to use vmnic2 and vmnic5

vSwitch2 (VM Network) - configured to use vmnic3 and vmnic1

My question is - can i Remove vmnic1 from the VM Network on the host with the issues and Add it to the iSCSI vSwitch1 and Remove the vmnic5 from iSCSI swith and Add it to the VM Network (esentially swapping the vmnic's)?

Are there any gotcha's?

Have looked for documentation all day and have not found anything that matches my situation.

[a_p_ · Accepted solution]

Once you made sure that the vmnics have indeed ben mixed up, you may fix the issue by either reconfiguring the network setup, or by simply swapping network cables. In any case I'd recommend that you do not have any VMs running on that host while modifying the configuration. I don't expect any issues with vSwitch2, but you may run into temporary issues with the storage (iSCSI) connection on vSwitch1. The port groups on the iSCSI vSwitch1 are VMkernel port groups, where each one of them has an active, and an unused vmnic configured, and iSCSI port binding may also need to be reconfigured if you're going to exchange vmnics on these two vSwitches.

André

[Dave_the_Wave]

I would make sure I can use the latest vmtools available for the GOS, there are vast improvements on vmxnet3 on each build.

With only 2 hosts, I can't imagine your amount of traffic to exceed two Physical Adapters per host, so I would take a chance pooling them together as discussed here by VMware Support:

Re: How to use vmnic0 and vmnic1 properly for performance?

Try to get that working again like so, then troubleshoot from there, and rebuild your 3 vSwitches.

It's one thing to keep a production environment running until its last legs where changes can be disruptive, but since you said this was a test lab, you should try things that take the least amount of time, including the opportunity to try 5.5 or 6.0 (new installs when possible).

[LAHCincy]

Swapping the cables fixed the problem.

Thanks for the help!