cucm cluster migration due to domain change

[Rajib Shovan]

Hi SMEs, please help by sharing procedure or best practice for cucm 10.5.2 cluster migration due to domain change. As per current setup, we have two cisco ucs c220 M4 servers each with capacity of 1TB datastore and 64GB memory.

UCS1 has used 530GB datastore (around 110GB per VMware host for call manager, and 200 per unity connection) and ucs2 has used around 420GB datastore. please refer to attached diagram for current cluster design.

We want to use the same resource and minimum user interruption during the cluster migration.

Thanks for your help.

[Jaime Valencia]

If you mean you need to move to a new server, use DRS, or vMotion.

The domain name change is completely separate from moving the servers.

[Rajib Shovan]

Hi Jaime,

We want to use the same servers by creating instances of new VMware servers (cm & uc pub and sub) in new domain. then we shall delete the old cluster. the main challenge might be the hardware datastore resources.

We were thinking to merge the cucm call manager and tftp/MoH functionality in existing cluster to free up some resources for standard implementation of new cluster, so that the new cluster will be in same design (as per the attached) after the migration.

Any more thoughts will be appreciated. Thanks.

[HARIS_HUSSAIN]

Dear Rajib,

What do you mean when you say 

10.5.2 cluster migration due to domain change

We can simply change the CUCM,Unity,IMP Domain without need to reinstall then on New VM.

Reasons we would reinstall on New VM is if we are upgrading hardware, Or If we want to change the CPU of the Underlying VM.

Please refer below guide for CUCM 10.5.2 Upgrade

http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/upgrade/10_5_1/cucm_b_upgrade-and-migration-guide-105.html

Thanks

Please rate and mark useful Posts

[Rajib Shovan]

Thanks Haris. Reason behind the new VM installation is the change of company domain: LDAP, DNS, NTP, VG configs all need to be changed in that scenario. and we don't want to buy additional ucs hardware to install new cluster. Rather, want to create replica of the new cluster in existing hardware and transfer the phones, users etc. to new cluster without impacting the uc services. Hope it answers your query.

Your response is appreciated. any related documents you would like to refer? Thanks again.

[Chris Deren · Accepted solution]

There is no need to rebuild the Cisco environment for domain changes, you can simply change all corresponding settings from within the solution to point to new domain.

I.e.

change DNS servers on the virtual machines

change the domain on servers

point to new LDAP

potentially change Top level domain in CUCM

Sign new certs if using CA signed certs.

update DNS on CIMC, ESXi, etc

[Rajib Shovan]

Thanks Chris for the clear direction. Is there any specific document from Cisco on this?

[Rajib Shovan]

Hi Chris, how much is the chance of database corruption in case of corresponding setting change (like DNS change)? And in this particular scenario, what could be the possible downtime? Thanks for your valued feedback.

[Jitender Bhandari]

Hi Rajib

There are very less chances of database corruption or replication going down because, most of the time we have seen above issue when the hostname or IP address changes don't take effect.

Refer to below for help.

https://supportforums.cisco.com/document/12413781/how-change-dnss-ip-address-publisher-call-manager-105

JB

[Rajib Shovan]

Thanks JB. How much downtime (in hours) should I consider for appx. 1000 users? Really appreciate your reply.

Rajib 

[Jitender Bhandari]

Hi Rajib,

Warning: Will tell you "This will cause the system to temporarily lose network connectivity"

It does not specify any specific number but it, looses connectivity for small time about 1 min might may be less than that.

JB

[Rajib Shovan]

Hi JB,

Another thing, existing CA certs will have to remove and new CA needs to be signed. do u foresee any risk? Thanks again

Rajib

[Jitender Bhandari]

Hi Rajib

In the warning itself it says 

Certificates need to be regenerated

WARNING: To avoid license synchronization failures, delete the product instance from the Cisco Prime License Manager managing this server's licenses before changing network settings.You will have to re-add the product instance after the network settings have been changed. This Operation would take time as Certificates need to be regenerated."

As you are using self signed certificate you will have to get it reissued from you CA.

(Rate if it help)

JB