CUCM 9.1 virtualization from MCS to UCS

[Ren Stark]

Friends,

I am in the process of Virtualize the CUCM 9.1 cluster from MCS to UCS. I have a plan to upgrade to 11.5 also.

I never done this before, I know, this is critical , needs lot of pre work. 

Anyone done this virtualization ? what is the best way of doing this, to have minimal downtime and succesful migration?

PCD migration is the good option or Can I do DRS backup and restore.

Note : we decided to keep same IP address and hostname.

Please share your thoughts and experience , that really help for me.

[Jaime Valencia]

Easiest way is PCD, but you'd need to build an isolate network to keep the same IP as production.

DRS is also an alternative if you don't want to use PCD

[Roger Kallberg]

As java wrote PCD is the easiest option. Why do you need to keep the same IPs, it would be much simpler if you change it. At least during preparation of the new virtual environment. Afterwards you can change the IP by following the process for that, it’s pretty straight forward.

DRS would also be an option, but for this there are a few gotchas to think of.

1. IP must be the same.

2. Host name must be the same.

3. Version must be the same.

The last means that you’d have to first install the current version in the virtual environment and do the restore from DRS. Then upgrade to the final version. All in all this is a pretty time consuming operation.

[Ren Stark]

Thanks Roger. I agree PCD is simple way of migration, but if I change the CUCM IP address, then how phone knows the new IP addresses?  Do we need to configure tftp IP on all phones manually? there are around 5k phones on the cluster. How to mitigate this?

[Roger Kallberg]

That is not really a problem. The phones get the configuration information from the TFTP server and they know how to contact the TFTP server by getting the IP for this via DHCP. In the DHCP server on the scopes for IP networks you change this by modifying option 150, or 67 if you still use that legacy option.

One additional thing to have in mind is that from CM8 there is a thing called Security by default. You should google this to know how to handle this when it’s time to move the phones from the old CM to the new.

[Ren Stark]

Thanks. But we are not going for network change. The plan is to keep the same IP address and hostname.

Is there a way to create similar cucm cluster with different IP address on the same subnet and restore DRS backup. Once all configuration is completed, can we power off the old cucm server and change the IP address to the actual IP  using PCD or any other way? 

Is this possible ?

[Roger Kallberg]

With DRS that’s not possible. But as I wrote in my first response you can do that with PCD.

How to change IP is described in this document. https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/install/11_5_1/ipchange/cucm_b_change-ip-address-and-hostname_1151.html

[Jaime Valencia]

Read

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/drs/9_1_1/CUCM_BK_D9A29FAD_00_disaster-recovery-system-cucm-91/CUCM_BK_D9A29FAD_00_disaster-recovery-system-cucm-91_chapter_01.html#CUCM_TK_R25ECCA6_00

[TONY SMITH]

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@Ren Stark wrote:

Is there a way to create similar cucm cluster with different IP address on the same subnet and restore DRS backup.

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If your cluster can survive the Publisher being out of service for a while you can follow the process I've used a few times.  Build new Publisher with the same details as the existing, but in an isolated environment.  You'll need something to simulate your existing NTP server.   Then when you're ready to swap over, take a DRS backup, shutdown or disconnect the old Pub, connect the new one and do DRS restore.

For the subscribers just shut each one down and build new in the virtualised environment.

In each case you need note any options installed like dial plans, country locales or other bits and pieces, and load all these into the new VMs.

[Ren Stark]

Tony, thank you for the great idea. Please check out my plan and advice.

1. Create similar CUCM cluster in the UCS virtual server, with difference IP address(to reduce downtime for installation)

2. On the day of migration, shut the production servers

3. Change the IP address of the CUCM virtual server as  production server IP address

4. Start restore the DRS backup of the configuration starting Publisher and followed by Subscribers

I never done a DRS restore before, please guide me what are the key points to be noted when restore the backup.

How do I check the options installed like dial plans, country locales or other?

[TONY SMITH]

I would do it the way I suggested.  Remember you can migrate the servers one at a time, there is nothing whatsoever wrong with having the Publisher running in VMware while the Subscribers are still on MCS.  Ideally keep the profile matching, for example if the MCS was 7835 then use the 2500 phone profile in VMware.

This way you don't have the whole cluster out of service.

DRS restore process is .. 

1. Shutdown or disconnect old Publisher

2. Startup or connect new Publisher

(At this stage the Publisher has an empty database but does not affect the Subscribers, as they are not configured on the new Publisher so can't talk to it)

3. Start the DRS restore

Last time I did this we did all the prep and stages (1) and (2) with everything live, then waited till after hours to do the DRS restore.   So I don't know for sure whether there were phone resets or restarts triggered during the process.

"How do I check the options installed like dial plans, country locales or other?"

CLI command "show version active" will tell you everything that's been loaded.  It may show a load of obsolete stuff as well, for example if various phone loads have been updated over the years then you'd only need to load the most recent version of each.  Same with Locales or Dial Plans, you only need the current versions.   So some detective work will be needed.

As always with a major change, check the Cisco documentation, see ...

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/install/9_1_1/replace/CUCM_BK_R1B1A464_00_replace-server-cluster-cucm-91/CUCM_BK_R1B1A464_00_replace-server-cluster-cucm-91_chapter_010.html

[Ren Stark]

Thanks for the details.

I do not understand this "Ideally keep the profile matching, for example if the MCS was 7835 then use the 2500 phone profile in VMware"

I have asked the downtime for the entire cluster, so would like to stick with my plan.

Also I would like to use the one-step restore feature, so that I can restore the DRS backup restore to Publisher and all the subscribers at the same time. Whats your thoughts on this?

[TONY SMITH]

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@Ren Stark wrote:

Thanks for the details.

I do not understand this "Ideally keep the profile matching, for example if the MCS was 7835 then use the 2500 phone profile in VMware"

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When you create the VM with the Cisco OVA you select the size option that you want to deploy.  I was recommending choosing the size equivalent to your old MCS models.  However if you're replacing the whole cluster at once then it probably doesn't matter, choose the size that will suit you from now on.  Use the same profile for all the new VMs.

If you can afford the downtime then your plan works.  Either way there is only one DRS restore needed.  Replacing a Subscriber as a separate step doesn't need a DRS restore, or at least we've never done so.

One thing to remember is licensing, particularly if your licences are hosted on ELM on one of the MCS servers.  Last time I did this we needed to get the licences re-hosted by Cisco.  So I would advise checking if you have your original licence files, and also save a Licence Request from the old ELM.  

[Ren Stark]

Thanks for all the clarification. It seems i need to install some device pack and cop files in addition.

At which time I need to install these files? Once DRS restore completed?

Do I need to install all the cop files in each CUCM nodes?

Or I can install these files now(before backup restore cucm vm's with difference IP address)

[TONY SMITH]

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@Ren Stark wrote:

Thanks for all the clarification. It seems i need to install some device pack and cop files in addition.

At which time I need to install these files? Once DRS restore completed?

Do I need to install all the cop files in each CUCM nodes?

Or I can install these files now(before backup restore cucm vm's with difference IP address)

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Install the COP files before doing the DRS restore, and it doesn't matter if it's before or after the IP address change.  Locales, phone loads and dial plans need to be installed on each node.