Can I safely change DNS servers in CWMS 2.5 without affecting the license?

[joergwesely]

Hi,

I have to change the DNS servers on the three VMs of a Webex Meeting Server 2.5. As the license manager is embedded, I'm concerned that this change could require a license rehost. Is this the case?

The VM's host names and IP addresses stay the same, but the DNS servers are replaced an their new IP addresses need to be configured on all clients including the Webex VMs. 

The documentation says this is changed by activating Maintenance Mode, change the setting under System/Properties/<VM> and deactivating Maintenance Mode again. (http://www.cisco.com/c/en/us/td/docs/collaboration/CWMS/2_5/Administration_Guide/Administration_Guide/Administration_Guide_chapter_01110.html#task_69757B2D9BF5405FB95E144F4E6EA054)

Thank you in advance

Jörg

[dpetrovi]

Hi Jorg,

Are the previously configured DNS servers still accessible? This is crucial as the change of DNS IP address in VM configuration won't be possible via GUI if the original DNS servers aren't reachable.

If original DNS servers aren't reachable, open a TAC ticket to work with TAC engineer on changing DNS configuration in boot config files in CLI of the VMs.

If original DNS servers are reachable and still working, you should be able to set new DNS servers via GUI by editing the setting of each VM and enter new DNS server.

As for Licenses, they shouldn't be affected as you are not changing your hardware and system ID shouldn't change either. Even if for some strange reason this happens, you will be granted 180 days grace period to address this, and licensing team will be able to rehost the licenses for you.

-Dejan

[joergwesely]

Thank you for this information.

Yes, the old and new servers are accessible and the system is accessible and runs without any issues, so I will perform this change tonight.

[mcecilia]

Thanks for your answer. The problem could be that old DNS server are still in service but with some problems with WebEx names/IPs. Exactly, what do the old server need to solve in order to be able to make the changes using GUI? Name to IP , IP to Name??

BRs