strange network problem after moving VM to another ESX server

[shechtl]

We have 3 esx4i server build 193498 with 2 nfs storages for about 20 VMs.

If I move a VM from one esx to another the VM it is no more pingable, but if the VM has dhcp it gets a ip adress, but also I cant ping from this VM anything.

Reboot of the VM does not help. The problem occurs most of the time.

To solve it I had to disable the NIC connection enable the NIC connection and reboot the VM. After that its running.

or I have to remove the nic, put it in again

I tried it with flexible and vmx3 adapter. Same problem.

For moving a VM I do :

1. Remove the VM from the inventory

2. Browse for the vmx file on the new esx server and put the machine in the inventory.

I did this a lot of time before with older release of esx 3.5 and never had any problem. Maybe its a bug in this release.

If I leave this machine in the inventory of all 3 esx server and start this VM on all esx (on after another) it worked and I have no problems.

So the problem comes if I put the VM fresh again in the inventory.

I find a little bit more.

If I start the vm on the new esx and the ping from external ist not working, also a ping from the esx server console is not working and also from a another vm on the same as esx is not working.

So I can say its not a problem of external switches etc.

I leave this non pingable machine running and after 8 Minutes the ping was coming from alone.

Is there anything on the esx which takes about 8 minutes ?????

I checked MAC adress, but its always the same, because I only moved the machine (and thats ok)

We use only vsphere client, not vcenter.

Hope anyone could help.

MAC Adress on switch stays the same.

I tested a little bit more. If the problem occurs its enough to shutdown the VM, change any entry in the vm machine konfig (for example disable the floppy) and start the machine. After that the NIC works.

So changing anything in the konfig helps to solve this problem.

[ZBali]

Hi,

After you change host see the mac-address table on your switch interfaces... Are they change too?

[shechtl]

do you mean the virtual switch in esx, anf if yes where can I find a mac table there , or my physical switch ?

[ZBali]

In the physical switch

[shechtl]

MAC Adress on switch stays the same.

I tested a little bit more. If the problem occurs its enough to shutdown the VM, change any entry in the vm machine konfig (for example disable the floppy) and start the machine. After that the NIC works.

So changing anything in the konfig helps to solve this problem.

What could this be ??? The esx server are all on same build version. It looks like a bug in esx

[J1mbo]

Can you ping another VM running on the same ESX host as the problem VM? Assuming they are connected to the same LAN that is.

Also, do your vSwitch port group names match exactly between the hosts?

Please award points to any useful answer.

[shechtl]

other VMs on the new host are pingable, vswitch group name are exactly the same.

[J1mbo]

To clarify, the VM that isn't working correct can however ping VMs that are running on the same ESX host?

Are the properties of the vSwitch set to notify switches (see attached)?

Please award points to any useful answer.

[shechtl]

That was a missanderstanding.

The NOT working VM is not able to ping anything (other VMs on same esx, all other hosts, ..) no Ping anyway. But its strange that a dhcp release and renew on this maching is working, but thats all

vSwitch is set to notify switches

[J1mbo]

Have you tried creating a new vmx file for this host, i.e. remove from inventory, datastore browser, rename vmx, new host, use existing vmdk.

Please award points to any useful answer.

[shechtl]

like descripted before its enough to change any parameter in the vmx file (f.e. disable floppy), reboot the vm and it is working.

I compared the vmx files before and after moving to the new esx. They are 100% identically

[shechtl]

I find a little bit more.

If I start the vm on the new esx and the ping from external is not working, also a ping from the esx server console is not working and also from another vm on the same esx is not working.

So I can say its not a problem of external switches etc.

I leave this non pingable machine running and after 8 Minutes the ping was coming from alone.

Is there anything on the esx which takes about 8 minutes ?????

[DSTAVERT]

It could still be a physical switch issue. The switch could have an issue with MAC tables. If this is a managed switch it could have settings.