VMware Cloud Community
sim80n
Contributor
Contributor
Jump to solution

vMotion VMkernel Network Migration

I need to migrate our vMotion VMkernels to a different subnet which seems easy enough: change VLAN in Port Group and then update static IPv4 setting on each VMkernel.

Before I proceed though, I wanted to see if anyone had done this procedure with a stretched vSAN cluster. We have 2 data centers in our internal network with the vSAN cluster stretched between and each DC has it's own IP range. We are running vCenter/ESXi 7.0 u2 btw. I was thinking I might have to do something with the static routes on the hosts but am not sure. Any advice would be appreciated. Thanks.

Reply
0 Kudos
1 Solution

Accepted Solutions
a_p_
Leadership
Leadership
Jump to solution

Yes, see step 9 in the documentation.

Please  be careful that you do this only on the "vMotion" TCP/IP Stack. Overriding the default gateway on the "Default" Stack is not what you really want/need 😉

André

View solution in original post

12 Replies
a_p_
Leadership
Leadership
Jump to solution

Please provide details about the configuration in both DCs to better understand the current state.
How is vMotion configured right now? Is it set up as a dedicated IP-Stack?

André

Reply
0 Kudos
sim80n
Contributor
Contributor
Jump to solution

Yes, each host has a separate VMkernel adapter for vMotion with an IP from the subnet that is local to each DC's IP range, 10.100.x.x for one DC and 10.200.x.x for the other DC.

Reply
0 Kudos
a_p_
Leadership
Leadership
Jump to solution

The question is whether vMotion uses it's own "IP Stack".

André

Reply
0 Kudos
sim80n
Contributor
Contributor
Jump to solution

I select vMotion in the VMkernel settings which I believe creates a separate TCP/IP stack, see attached screenshot. Is that what you are asking about?

Reply
0 Kudos
a_p_
Leadership
Leadership
Jump to solution

Selecting vMotion at the point in your screenshot only marks the prot group as a vMotion port grou, but does not create a separate stack. Please see Place vMotion Traffic on the vMotion TCP/IP Stack of an ESXi Host for how to configure the vMotion stack to allow routing.

André

Reply
0 Kudos
sim80n
Contributor
Contributor
Jump to solution

That screenshot is of the VMkernel not the Port Group. Thank you for providing that link, that is exactly how I created the VMkernels for vMotion on my hosts so I guess they do have a separate TCP/IP stack.

Reply
0 Kudos
a_p_
Leadership
Leadership
Jump to solution

Your screenshot shows that you may have missed to select the vMotion TCP/IP Stack from the drop down menu as mentioned in the documentation (step 7). You've created the vMotion VMkernel port group in the "Default" stack

a_p__0-1632491300522.png

André

Reply
0 Kudos
sim80n
Contributor
Contributor
Jump to solution

Ah I see. Thank you for helping me understand how to create a separate TCP/IP stack in the VMkernel. Would it be best to create new VMkernels with separate stacks and the new subnet that I need to migrate the vMotion service over to?

Reply
0 Kudos
a_p_
Leadership
Leadership
Jump to solution

From what I understand so far about your network configuration, yes, you may create the vMotion VMkernel port group in its own stack, which allows you to specify a gateway address for that TCP/IP stack.

André

Reply
0 Kudos
sim80n
Contributor
Contributor
Jump to solution

Is that the same as the "Override default gateway for this adapter" option available on the VMkernel settings?

Reply
0 Kudos
a_p_
Leadership
Leadership
Jump to solution

Yes, see step 9 in the documentation.

Please  be careful that you do this only on the "vMotion" TCP/IP Stack. Overriding the default gateway on the "Default" Stack is not what you really want/need 😉

André

sim80n
Contributor
Contributor
Jump to solution

Awesome. Thank you for all of your help!

Reply
0 Kudos