Help to Understand the CUCM DRF feature component

[Ren Stark]

Hi,

I am working on virtualize the cucm 9.1 from MCS to UCS. Its already EOL/EOS. The plan is to first migrate to UCS then upgrade to 11.5 using PCD. I gone through many community pages and came to know people stuck during the DRS restore with deployment model error. Also the provided solution is do not restore the ELM feature. then rebuild the ELM manually. If I left the ELM feature while restore , then how do I rebuild it?

Can anyone came across this case? migrate the cucm 9.1 from MCS to UCS successfully using DRS restore?

 Can you help me understand what are these feature exactly ( CDR_CAR, UCM, ELM )?

[TONY SMITH]

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@Ren Stark wrote:

Can anyone came across this case? migrate the cucm 9.1 from MCS to UCS successfully using DRS restore?

 Can you help me understand what are these feature exactly ( CDR_CAR, UCM, ELM )?

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Yes we've done this, it was pretty straightforward.  Build new CUCM publisher in VMware using same settings as the existing one, then restore from DRS backup.  The existing Publisher needs to be offline during this process.  For the subscribers we just switched off the physical servers and installed new into VMware.   All these are the same process as documented for "replace a single server or cluster"

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

At a later date we did an in place upgrade from 9.1 to 11.5, I don't see a big benefit in using PCD for that.

However with PCD I think you can go straight from 9.1 on MCS to 11.5 on VMware as a "migration" rather than upgrade.  Not something I've done myself though.

Another thing to consider is that with 9.1 being end of support for over a year now, you might not get a lot of help from Cisco if you hit a problem migrating 9.1 on MCS to 9.1 on VMware.   I would like to think that if a support contract is in place, then they would assist if you hit issues with the upgrade to a supported version.  This might be another point in favour of the PCD migration.

[Ren Stark]

Thanks for the details Tony.

I have already built CUCM 9.1 cluster in VMware with difference IP address. On the day of Migration, I will shutdown the current servers and change the IP address of VMware CUCM server then do the DRS restore. I would like to do one-

step restore. All I am worried is, since the DRS restore is from MCS to UCS, will I hit into deployment error?

Because I do not know the deployment model of MCS server also, the vmware CUCM is not built with Cisco OVA, since it is 9.1 , I did not get that.

In case of deployment error while DRS restore, do I need to exclude the ELM component then try? If that worked how can I rebuild the ELM part?

[TONY SMITH]

You need to use the Cisco OVA to create the virtual machine.  Not doing so may cause some problems down the line, and if nothing else Cisco TAC will notice if they're investigating a fault.

I'm not sure about the deployment error that you're concerned about.  We didn't have any issue when I did this. 

Nor am I quite sure on the ELM question, I suspect that if you exclude ELM from the backup or restore then you will just have an empty ELM instance and need to re-add the applications.  That wouldn't be a big deal.  However remember that this is a non destructive process. If you're not happy with the result of the restore, or it fails, then just switch off the new VMs and reconnect your old MCS servers.  Personally I'd probably do it one server at a time.  Migrate the Publisher while leaving the Subscribers still on MCS, then build them new on VMware as a subsequent stage.

Something else to think about, you will need the licences re-hosted to the new ELM.  Will Cisco still do this for an end of support product.  Might be worth an email to licensing@cisco.com before hand.

Do you have support in place for the intended 11.5 software?

[Ren Stark]

Thanks Tony for the details . I am reffering the below errors while restore the backup

https://community.cisco.com/t5/unified-communications/call-manager-drs-restore-deployment-type-mismatch/td-p/2706083

https://community.cisco.com/t5/ip-telephony-and-phones/drs-error/td-p/2045055

I do not have a contract for CUCM 11.5 yet. But have the contract for UCS servers

[TONY SMITH]

The first example look as if he was trying to DRS restore to a smaller profile than the original server.  This is referring to the option you choose when the OVA file is deployed.  You can go larger but not smaller, so you should match your MCS size or increase.  So for example if it was an MCS 7825 then you can choose the 1000 user profile (or bigger),  if it was a 7835 then it needs to be 2500 user or bigger.

[Ren Stark]

Thanks Tony. The challenge here is I am not getting the OVA template for CUCM version 9.1 also the device pack

[TONY SMITH]

It's true that Cisco has quite aggressively removed the downloads for 9.1 as soon as it went end of support, inconsistently for some things you could still download the version 8 stuff but not version 9.

You could try the 10.x OVA.   I say try because I got caught once trying to be clever, I was installing a new 8.6 Sub that was going to be upgraded almost immediately to 11.5, so I used the OVA for 11.5 but found 8.6 would not install.  The type of network adapter was incompatible.

[Roger Kallberg]

Use a newer OVA and manually change anything that would be different. The thing that you should not change is hard disk setup as that will invalidate your setup.

[Roger Kallberg]

This old post has good information about the v9 OVA.

https://community.cisco.com/t5/unified-communications/number-ov-vcpu-for-ucm-9-1-ova/td-p/2261733

[VoIP Engineer]

I'm working on a 9.1 -> 11.5 upgrade at the moment as well, and wanted to add my 2 cents.

I would do my best to not change anything (i.e. same IPs, hostnames, etc).  You don't want to end up in a situation where your phones won't register to the new cluster, and need to be reset.  Once everything is completed, you are on 11.5 and you have your contracts in place - that's when I'd change IPs, etc.