Problem migrating a VM with multiple vCPUs

[brian_jones]

When I try to migrate some of our VMs with vMotion I get the following error.

"Unable to migrate from host a to host b: Virtual machine has 4 virtual CPUs, but the host only supports 1. The number of virtual CPUs may be limited by the guest OS selected for the virtual machine or by the licensing for the host."

Both ESX server are identical HP DL380's with two quad core Intel Xeon's. They are both connected to the same vCenter (2.5) server. They both are using the same license server. And, the VM OS is set to Windows Server 2003, Enterprise (32-bit),that should support 4 vCPUs (it does now after all).

I tried moving a powered off VM and got the same error, so I changed the vCPU to 1 and it migrated fine. Then, I changed it back to 4 vCPUs without any problem on the new host. Only problem is, I can't shut down some of the VMs just to migrate them to the new host due to uptime requirements.

~Brian

[Texiwill]

Hello,

"Unable to migrate from host a to host b: Virtual machine has 4 virtual CPUs, but the host only supports 1. The number of virtual CPUs may be limited by the guest OS selected for the virtual machine or by the licensing for the host."

Could be a license issue. Also do you have a vSMP license for the second node? Check out the license manager server tools for help.

Both ESX server are identical HP DL380's with two quad core Intel Xeon's. They are both connected to the same vCenter (2.5) server. They both are using the same license server. And, the VM OS is set to Windows Server 2003, Enterprise (32-bit),that should support 4 vCPUs (it does now after all).

I tried moving a powered off VM and got the same error, so I changed the vCPU to 1 and it migrated fine. Then, I changed it back to 4 vCPUs without any problem on the new host. Only problem is, I can't shut down some of the VMs just to migrate them to the new host due to uptime requirements.

Check out 'Opscheck' from http://www.vwire.com/free-tools/opscheck/ to help diagnose this problem.

Best regards,
Edward L. Haletky
VMware Communities User Moderator, VMware vExpert 2009
====
Author of the book 'VMWare ESX Server in the Enterprise: Planning and Securing Virtualization Servers', Copyright 2008 Pearson Education.
Blue Gears and SearchVMware Pro Blogs -- Top Virtualization Security Links -- Virtualization Security Round Table Podcast

[brian_jones]

Could be a license issue. Also do you have a vSMP license for the second node? Check out the license manager server tools for help.

All the servers are licensed with the same vCenter license server and do not have problems running 4 vCPUs after they are migrated. Is there a special license needed to migrate a multi-cpu VM?

Check out 'Opscheck' from to help diagnose this problem.

I have the same issue when I tried migrating a powered off host without using vMotion (just the vCenter "migrate" option). I installed/configured vMotion later to move the running VMs and still got this error.

[Texiwill]

Hello,

All the servers are licensed with the same vCenter license server and do not have problems running 4 vCPUs after they are migrated. Is there a special license needed to migrate a multi-cpu VM?

In this case it is not a license issue.

Check out 'Opscheck' from to help diagnose this problem.

I have the same issue when I tried migrating a powered off host without using vMotion (just the vCenter "migrate" option). I installed/configured vMotion later to move the running VMs and still got this error.

Check out Opscheck first. Fix any problems it finds then try again.

Best regards,
Edward L. Haletky
VMware Communities User Moderator, VMware vExpert 2009
====
Author of the book 'VMWare ESX Server in the Enterprise: Planning and Securing Virtualization Servers', Copyright 2008 Pearson Education.
Blue Gears and SearchVMware Pro Blogs -- Top Virtualization Security Links -- Virtualization Security Round Table Podcast

[TomHowarth]

Do you have reservations on your Guest, it could be that you do not have enough resource left to service another quad core guest.

If you found this or any other answer useful please consider the use of the Helpful or correct buttons to award points

Tom Howarth VCP / vExpert

VMware Communities User Moderator

Blog: www.planetvm.net

Contributing author for the upcoming book "VMware Virtual Infrastructure Security: Securing ESX and the Virtual Environment”.

[brian_jones]

Do you have reservations on your Guest, it could be that you do not have enough resource left to service another quad core guest.

Nope... No resource pools, reservations, etc. Each server is running 3-4 VMs.

[kjb007 · Accepted solution]

Have you tried to edit your license settings, and applying them, just in case? I have had weird services failing when there is some sort of latency hitting the license server from the ESX hosts.

-KjB

VMware vExpert

[brian_jones]

Have you tried to edit your license settings, and applying them, just in case? I have had weird services failing when there is some sort of latency hitting the license server from the ESX hosts.

-KjB

VMware vExpert

That was it!!!

It looks like somebody has changed one of the rules in the firewall and blocked the ESX server from talking to our license server. When I went into the license page it took about a miniute to load and then stated I was running an expired trial license. Once the firewall rule was corrected I went back in and it pulled the correct license from our server.

Now, the VM migrates just fine.

[brian_jones]

Also, I gave helpful points to the OpsCheck utility post. That program is pretty slick, and it did find some errors on our dev servers that were causing problems.