cucm ip add and host name change question

[vijendra Saravanamuthu]

Hi,

i would appriciate if anyone can comment on this.

I will be changing ip address and host name of one of the subscribers (6.1.x) in our cluster.  This server will be moving a different building  the new ip add vlan.

i did read the documenation for changing ip add/host name in the following URL:

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/install/6_1_2/ipchange/ipchg612.html#wp185718

I have 2 questions:

1. I understand that we first have to change the system->server to the new ip address before changing default gw/ip add. however, i will only get to change it when the subcriber is brought to the new building.  at this point i cannot power up the server , have it join the cluster, then change the ip add in system->server, then update the default gw and new ip since the new building vlans will not allow the current ip to gain network access.  i can make this system->server ip add change in the cluster but this server will not in part of the cluster at that time of change. so it wont get the update. 

so my question is..do i have to cahnge this system->server ip add while all servers are up and running and then bring down this particular server, move it to new building and change the gw/ip add there.??

2. how many times do i have to do cluster reload?

my plan is to do ip add change first (so it will have network access) - this require cluster reload according to the doc. thats fine. but can i do this cluster reload for once after changing hostname as well?  i am thinking of chaning ip , reload cluster, make sure DB is good, and then move onto hostname with anothe reload of cluster. but this takes time. 

i can cahnge ip /gw then hostname and reload all servers onces. but if for some reason ip/gw change didnt replicate well and i go with hostname on top of that may screw things up.

thanks

vijay

[William Bell · Accepted solution]

Vijay,

How are you? Modifying the IP address and hostname can be tricky.

To answer your first question: One approach you can take is to stand up a VLAN at the current site that will use the same IP address subnet as provisioned on the new site. Then you can reconfigure the Server object in CCmAdmin (System>Server). Once you do this, go to the subscriber and verify the information is replicated (CLI: run sql select name,nodeid from processnode). Once replicated, go to the cmplatform portal on the subscriber and change the IP address info and hostname. Yes, you can change both the IP address and the hostname from the cmplatform portal (Settings>IP>Ethernet).

Using the above method, you can run with the new IP address in the "old" environment until you are ready to pack up the server and ship it out. You can then remove the VLAN and router configs. Bring up the network and server at the remote network, and move forward. Of course, you would have to look at your IP routing to ensure there are no gotchas such as static routes, or filters on redistribution, etc.

You should only have to do a cluster reload once. Unless something gets fowled up. I would consider stopping the CM service and maybe taking the subscriber out of CM groups (or disabling the service) if you anticipate or want to avoid a lot of churn.

HTH.

Regards,

Bill

[iptuser55]

Hi Bill

I`m doing a IP address change and a Host name change on a test cluster prior to our production system

When I change the Host name  and enter run sql select name, nodeid from ProcessNode on the servers I`ve seen all the servers returing the correct response but on the actual Sub I`ve seen the "old" host name still appearing

Question -

What does the commend check against is it the Host files ?

Is there a commend to fix the correction

Process

Change the Server name on the Pub

Access Sub change the Server name in the OS page or via the CLI SET NETWORK HOST.....

Check update via utils network host .......

Pub utils dbreplication reset all

Basically our test clsuter is built on different IP address and Host name`s , we are doing a HW upgrade so the idea is to do a

Chaneg License files etc

DRS of the production system

Shut down the produciotn system

Change IP address and Host name of the Test system

Restore to "test" system  

[ashok_boin]

Hi,

The following link gives you detailed procedure to perform your activity.

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/install/6_1_2/ipchange/ipchg612.html

Regards...

-Ashok.

[William Bell]

iptuser,

The "run sql" command is actually querying the local copy of the database on the host where you ran the command. So, when you don't see the information updated in the subscriber's database, this means you may have a replication issue.

You should check db replication on the server. Your next actions are determined by state of replication.

HTH.

Regards,

Bill

[iptuser55]

Hi Bill

thanks for the reply

The strange is

CLI on Sub concerned

show myself, show tech network host all reply back with the correct Host name however the run sql..... replies back with the "old" host name

If I do a utils network connectivity "host name of sub from show myself " then it replies back ok , if I enter the host name form run sql select..... then it fails

[vijendra Saravanamuthu]

Hi Bill,

i really appriciate your help.  i understand we have to create the same vlan in the in the existing enviroment to get this going properly.  that might be a problem with the customer.  I will bring it to their attention for sure.

but just to clearify,

i will have all the servers in the existing vlan, change the server ip add in (system->server),  put the particular sub in the new vlan, then change the ip add/gw/host then bring it over to the new site and plug it in.

if thats the correct, then i am just wondering if the following is correct:- I change the  system->server ip in teh existing enviroment, once its propagated, i can shut down this sub, bring it over to the new site and plug it into the new vlan then change teh ip /gw/host. hows that?,

thanks

vijay

[William Bell]

Vijay,

yes, more or less that is the procedure. Specifically:

1. Create new vlan and router interface (SVI if L3 switch) MAKE SURE it is routable to the publisher vlan

2. In CCMAdmin, change the server config under system>server

3. Verify on the subscriber (via CLI) that the change replicated

4. In cmplatform of subscriber, change the IP Address and Hostname. This will trigger a reboot.

5. When the system goes down either swap cables OR reconfigure the network port to the new vlan

6. system comes online, performs validation, and you should check to make sure replication is healthy

Then you can run like that until you move to the new network.

If your customer doesn't like that plan then you can do the same thing you and packup/ship the server out. You will just have a delay between step 4 and 5. There is additional risk with this latter plan and it wouldn't be the route I would take, so I can't tell you from experience what to expect. Though, that is just a disclaimer and it should work.

HTH.

Regards,

Bill

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[William Bell]

iptuser55,

Sounds like you changed the IP address of the subscriber on the OS before changing the Server object under System>Server. I suspect that your database replication is not working.

At the CLI of Pub and Sub, run the command:

admin: show perf query class "Number of Replicates Created and State of Replication"

Output codes:

0 = replication not started

1 = replication created but counts are incorrect

2 = replication is good

3 = replication is bad

4 = replication did not succeed

Also, check the SQL query against the publisher to see what the value for the subscriber server object is. If the data is out of whack and you have something other than replication status of "2" then your db replication is broke. You may need to reset the subscriber IP addr/hostname on the OS (cmplatform), restart, and then fix replication manually. Once replication is fixed, then try the procedure again in the correct order.

HTH.

Regards,

Bill

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[vijendra Saravanamuthu]

Hi Bill,

i just have another followup question on this and i hope you can asnwser this.

once the hostname/ip add change is done, there is some post-change tasks listed in the URL:

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/install/6_1_2/ipchange/ipchg612.html

Step 7 Reconfigure the netdump server and clients by using the utils netdump CLI commands

do yoiu know what exactly this command does?  or does this only apply if publisher name/ip changed? anyways i would like to know what exactly that command does.  i was unabble to find anywherre about it.