ESXi 4.1 IBM x3250 M3 - Only 1 VM connects to external network at a time.

[Geoff007]

Hi,

I have 2 VMs on the host and the host has only one uplink so all trafffic flows out the one adapter.  The problems seems to be that only one VM can connect out to the external network at a time.

The configuration for vSwitch0 is dead simple (I've attached a screenshot).

This part is key, when I shutdown the VM that works and reboot the one that doesn't then it starts working.  Then if I start the VM that used to work, it doesn't work anymore.  So, they've essentially switches places.

It almost seems like the vSwitch can only handle one VM connected at a time.

Any thoughts?

[a_p_]

Welcome to the Community,

this is most likely a configuration issue with the port on the physical switch. Make sure the switch port is not configured for port security, which usually allows only 2 active MAC addresses (e.g. the host itself + 1 VM). For Cisco switches set "mode access" or deactivate/disable "macro desktop" on the port.

André

[Geoff007]

Hi André,

Thanks for the quick response.  I was wondering if it might have been something upstream, but never knew about that type of configuration on the switch.  I'll test against a hub and see if that makes a difference and let you know.

Thanks again,

Geoff

[Geoff007]

Hi André,

That seems to have been the problem because everything works if everything is connected via a hub.

Thanks again for your help,

Geoff