Microsoft NLB hang after upgrade ESX 5.0

[csyckad]

Hi All, I am new to vmware

We upgrade all our ESX from 4.1 to 5.0 at Feb, after that, many Microsoft NLB multicast will hang, before upgrade, we had used around 2 year without any issue.

After upgrade, we have 3 set NLB down or conflict during 3 month,

Any idea? in the guest VMware.log, I don't see any specific thing related to network during incident time.

Thank a lot

[julienvarela]

Hi,

Microsoft NLB multicast is fully supported in vmware and you don't need to take any special steps to configure your ESX host.

So 2 options :

-1 The issue is located on your Guest os. Check windows log.

-2  Maybe ARP is rejected by the switch.

You can check here : VMware KB: Microsoft Network Load Balancing Multicast and Unicast operation modes

Regards,

Julien.

[csyckad]

The NLB was setup long time and the issue happen after upgrade ESX 5.

Physical server didn't have any issue, only VM guest have issue now.

bu

Off course it is possible related to Windows issue, but I think it may also related to VM host, maybe the patch not update, we are using ESX 5  update 2. build number 914586

[csyckad · Accepted solution]

Opened the case to VMware and confirm this is known issue for Broadcom network Card

VMware KB: Broadcom 5719/5720 NICs using tg3 driver become unresponsive and stop traffic in vSphere