I am running approximatly 30 VMs on each of my ESX machines through Lab Manager and experiening some connectivity problems from time to time.

My connectivity problems occure while trying to connect to part of my virtual machines through SSH by getting a "No Route To Host" message.

Its important for me to mention that if I try to connect to the same virtual machines few seconds later, it connects ok.

That scenario happens again and again from time to time.

Each of my ESX machines has multiple separated giga nics for both Console/Virtual Machines network.

All My ESX + Vcenter +Lab Manager are located on a dedicated Cisco 2960G switch and storage use is EMC Clarion.

I tried to identify the problem by looking at the vcenter esx event log and found that I have some mac address conflict errors like the one mentioned below:

The static mac address (XX:YY:...) conflicts with mac address assigned to VM...

I would like to mentioned that all our configurations are deployed fenced only, so I see no reason for these conflicts to occure.

I guess that such a conflict may generate a connectivity problem as with regular networking problem.

My ESX version is: 3.5.0 110181

My Lab Manager version is: VMware, Inc.® Lab Manager 3.0 (3.0.0.2063)

My Vcenter version: 2.5.0 build 119598.

Is there a way I can try and monitor whats going on the ESX side and understand why do I get a "no route to host" in a non consitent way?

Thanks.