Question on vSwitches and physical upstream switch failure

[calleghf]

Hello,

I would like a question in relation to the behavior that I would experience in this situation:

I have two NICs in the following configuration using the default load balancing scenario

“Route based on originating virtual port”

According to this article when this policy is in use only one Vmnic is active and the other one is passive

https://kb.vmware.com/s/article/2006129

Let’s say that the Vmnic 6 is the active NIC and the upstream physical switch port on S1 below fails or the cable is pulled and that physical switch S1 gets completely isolated

Since the Network Failure Detection is set to “Link Status Only” my Vmnic 6 will not switch the traffic to the other Nic Vmnic 2 since it’s not aware that the upstream link

is down: I’m guaranteed that I lose all network connectivity from that host. Is that right ?

I know I can use Link Status and Beacon Probing , Link Failure Detection policies in the physical switch etc. but I was interested in the behavior of that particular scenario above.

Thanks a lot for any clarifications

Fabio

[daphnissov]

The scenario you're describing verbally is different from the scenario which is depicted in your screenshot. In the screenshot, you have two uplinks in an active state.

Let’s say that the Vmnic 6 is the active NIC and the upstream physical switch port on S1 below fails or the cable is pulled and that physical switch S1 gets completely isolated

Since the Network Failure Detection is set to “Link Status Only” my Vmnic 6 will not switch the traffic to the other Nic Vmnic 2 since it’s not aware that the upstream link

is down: I’m guaranteed that I lose all network connectivity from that host. Is that right ?

Yes, because although the upstream link has failed, you still have link to vmnic6. However, in the screenshot where both uplinks are active, without beacon probing, the traffic utilizing vmnic2 would be up.

[calleghf]

Thanks a lot Daphnissov for the quick reply and clarification.

Fabio​