Nexus 1000v VSM migration from VM to VSB (Nexus 1110)

[zykobot]

Hi,

I've read the documentation around migrating a VM VSM to a VSB:

(http://www.cisco.com/en/US/docs/switches/datacenter/nexus1000/sw/4_2_1_s_p_1_5_1/software/configuration/guide/n1010_vsvcs_cfg_6migrate.html)

There's a few questions I've got out of this:

- If you create a primary VSA, it asks for an management IP address - won't this conflict with the IP address active on the standby VSM which is now primary?

- Similarly, one of the last steps is to create a secondary VSA - it again asks for a management IP address, I tried this in another deployment and found the management IP addresses conflicted between the primary and secondary VSA, the only way I found to avoid this is by creating the VSBs from scratch and not specifying primary/secondary which of course creates primary and secondary at the same time.

Any one else been through this?

Thanks,

Nick

[zykobot]

Sorry.. I've used the wrong terminology above.. should be:

primary VSB and secondary VSB (not VSA).

[lwatta]

It shouldn't matter if you give the the ip address. As long as you give it the same domain id they should form a cluster. When you create the secondary VSB make sure to create it as secondary.

Also make sure there is L2 connectivity between your 1110 and the ESXi host so tthe cluster heartbeats can pass between the two VSMs.You need to make sure the control interfaces have L2 connectivity.

I will run through it in my lab today to make sure the steps are still correct.

What code revs are you using?

louis

[zykobot]

Thanks Louis,

Version is

nexus-1000v 4.2.1.SV2.1.1

Nick

[zykobot]

Hi Louis,

Have you had a chance to try this out yet..?

I'm not keen on rolling it out in Production if it's going to cause issues .

Nick.

[lwatta]

Working on it now. Should have answer or you in a little bit.

[lwatta]

I just ran through this twice to make sure I got it.

Take away #1. That document needs some clarification

>- If you create a primary VSA, it asks for an management IP address -  won't this conflict with the IP address active on the standby VSM which  is now primary?

No it does not conflict. Due to the way our HA mechanism works when the two VSMs see each other they go through an election process to determine which VSM should be primary. Since the ESXi-based VSM is connected to VEM modules and vCenter it wins out. The VSM on the 1010 goes into standby mode and the config is pushed to it overwriting anything that was assigned during the install process.

>- Similarly, one of the last steps is to create a  secondary VSA - it again asks for a management IP address, I tried this  in another deployment and found the management IP addresses conflicted  between the primary and secondary VSA, the only way I found to avoid  this is by creating the VSBs from scratch and not specifying  primary/secondary which of course creates primary and secondary at the  same time.

In this case I would guess that either the two VSMs could not communicate over the control vlan or the domain id was wrong. When you bring up the secondary on the other 1010 the same election process should happen as in the previous example.

If you want to see me run through it on a webex let me know.

louis

[zykobot]

I have to disagree with you on this one Louis,

Perhaps there was differences? Maybe your configuration was in L3 mode and that makes a difference.

I performed the migration as per the instructions and the VSM on the VM and the Nexus 1110-s would not elect a primary. Same domain ID was used and I could see MACs in all the relevent VLANs.

In the end I had to change the role on the Nexus 1110-s VSM 'system redundancy role secondary' and reboot.

Then the two VSMs sync'd.

However, same problem again when I created the secondary VSB (as both VSB's thought they were secondary). Only way to do it was make the Nexus 1110-s role as primary and reboot it.

Then turn on the secondary VSB.

Finally migration complete.

Nick.

[lwatta]

Ok. Let me try it again in both modes. I beleive I did do it in L3 mode, but that has little bearing on VSM to VSM connectivity.

I just had a very basic N1Kv config. I'll build a bigger environment this time and see if that makes a difference.

I should be able to run through this tomorrow.

One last Question. What the initial versions of your VSMs? Were they always 2.1? or did you upgrade from a previous version to 2.1?

louis

Message was edited by: Louis Watta