CUCM – Moving CUCM Publisher – Change IP address

Where do we begin with this one? – Here is your ticket and before you go to the next section of this post, make sure you have a quick answer.

The Ticket/Challenge **Trying not to call it a problem!

Your client needs to move from a Datacenter to a new location. You need to move the CUCM Publisher and be able to do it also by changing the IP address, with minimum service impact as possible

To the Drawing board with this one

In order to not have any downtime, we have to make sure we leave the current environment untouched. I have an idea for that, here are the ingredients we need:

– OVA for CUCM x.x –> Where X.x is the version your CUCM is running
– OVA for CSR1000v –> This is going to be your Default Gateway + NTP Server + DNS Server (If needed)
– Production VLAN –> This is your final Subnet or the subnet where you will have CUCM after the move
– Black Whole VLAN –> Also known as “non-routable VLAN” – I like to call it my Upgrade/Migrate VLAN
– WINDOWS VM –> This one will have 2 NICs which you will need to change alternatively between the 2 Networks

** You already know where I’m going with this. We are creating an isolated environment, and we are getting a DRS Backup from our current infrastructure and we are Restoring it to the new CUCM in our Isolated environment.

Now, wait, the order of the factors may alter the final product!

Here is my Sanity checklist, which had to be done, just because it’s me and I keep forgetting stuff all the time


Installation is basic, no weird stuff here, I just like to rename my interfaces and assign an IP address from each of the Networks I will be using
From this VM, Get a DRS Backup from the Production environment

Install CSR1000v

Configure GI1 interface to have the same IP address as the Default Gateway on your Production environment
Configure NTP IP address as a Secondary IP address on GI1
Configure DNS IP address as a Secondary IP address on GI1
Set the correct time on Hardware
Make the Router your NTP Master at Stratum 4

Install CUCM

This installation is in the Isolated environment
Use same IP address
Use the same Subnet
Use same Default Gateway
Use same NTP server
Use same Security Password
Use same OS and Admin credentials **If not you will be hating yourself later 🙂
Make sure everything looks good

The Process

Initiate a DRS Restore on new CUCM
Make sure it works and that is 100% successful 🙂 and restart
Once processes are started and the server is up and running begin the IP address change:

CUCM Related Steps (Isolated environment)

Go to System –> Server –> Click find
Select your Publisher and change the IP address there
Go to System –> Cisco Unified CM –> Click find
Select your Publisher server and change the Cisco Unified Communications Manager Name to CM_xx.xx.xx.xx (note that xx.xx.xx.xx is the IP address of your server)
Go to System –> Enterprise Parameters
Make sure you change these to use the new IP address
Go to System –> DHCP –> DHCP Subnet
Change references to the old IP address to the new **Yes there are companies that actually use DHCP on CUCM, don’t ask me why 🙂
Go to Device –> Device Settings –> Phone Services
Change any reference to your old IP address to the new IP address, some hints are Extension Mobility and others you may have
Now let’s go under the hood of CUCM –> Connect using SSH

Change the Default Gateway and the IP address like this

Here is the syntax 
admin:set network ip eth0 ?
set network ip eth0 addr mask
addr    mandatory   IP addr to be assigned
mask    mandatory   IP mask to be assigned
gw      mandatory   IP default gw to be assigned

The final command:
set network ip eth0


There are some Cisco documents that say to change the Default Gateway first and then the IP address, this makes sense but did not work for me, so I had to run the previous command.
This will send a message to the SUBs telling them about the change
Make sure the server is restarted

CUCM Related Steps (Production environment)

Follow the same steps and after you send the restart to make sure you never turn it back on 🙂 ** I just made sure I made the NIC disconnected from ESXI

Change the SUBS to point to the new IP address of the PUB after all changes have been completed

set network cluster publisher ip xx.xx.xx.xx



Make sure replication is reset by running on the PUB and SUBs

utils dbreplication reset all


Make sure replication is back to normal after the Reset


Change DHCP Scopes on CUCM to new IP
Change IP Helper on Subnets to the new IP
Change the MGCP and CCM to reflect new IP on all Voice Gateways ***This will be done automatically at least for MGCP configuration
Change the Dial-peers on H.323 Gateways
Change the IP address from Call Recording Servers
Change the IP address from the Fax Servers
Change the IP address of the SIP trunks referencing CUCM by IP

Change CUCM integration with UCCX **This will take a while after entering Username and Password on UCCX Admin screen, if only if, your Publisher is the primary AXL server

What to look forward to?

Nothing special really, I followed this

About the Author:

Andres Sarmiento, CCIE # 53520 (Collaboration)
With more than 13 years of experience, Andres is specialized in the Unified Communications and Collaboration technologies. Consulted for several companies in South Florida, also Financial Institutions on behalf of Cisco Systems. Andres has been involved in high-profile implementations including Cisco technologies; such as Data Center, UC & Collaboration, Contact Center Express, Routing & Switching, Security and Hosted IPT Service provider infrastructures.

You can follow Andres using Twitter, LinkedIn or Facebook

3 thoughts on “CUCM – Moving CUCM Publisher – Change IP address”

  1. Great checklist and post! One thing I had made note of was to check whether the cluster is running Mixed Mode or Non-Secure Mode to avoid possible certificate issues with IP Phones registering to new server.

  2. Hi Andres,
    Great post, I am in the middle of moving our pub to a new data center w/ip change so this is very helpful.
    I am not sure what is happening at Production Environment step “Follow the same steps and after you send the restart to make sure you never turn it back”. Eventually this new Pub will be placed in the production environment correct? You are not taking another DRS with new ip addresses and restoring it again?

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