1. Was the virtual machine part of standard switch or distributed switch ?
2. Was virtual machine able to ping other virtual machine on the same host and same port group ( when it was restarted after the HA failure ) ?
3. If yes, then it could be something upstream to the ESXi . If you have multiple network adapter cards connected to the vswitch or distributed switch and the interfaces connected to the vmnic don't have identical configuration ( some vlan missing ) then you can encounter the same issue . It can also be possible , if MAC address table not synced properly on the physical switch .
4. You can check the port group configuration on both the host and make sure they can identical as well.
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thank you for your message.
1. yes, we have distributed switch.
2. I didn't test that, but I cannot ping from other host. I am going to test ping from vm on the same host.
3. I will check.
4. I will check.
a come back as soon as possible
If virtual machines can ping other virtual machines on the same host-same port group - then it's something upstream to the ESXi host .
Please let me know after performing the above check and we can check further .
Any update ?
I cannot make the test now because I have to make some operation before my holiday which start next week.
I try to test the new network configuration at the end of this week or after holiday.
thank a lot for your help