Pros and cons of CUCM cluster over WAN

[jaheshkhan]

May I know the pros and cons of CUCM cluster over WAN. I would like to know real time situation who already implemented.

I heard this design approach there will be possibility of inconsistency in database .. is it right?

routing and firewalling should be done properly right? while in production if some reason if some firewall policy messed up will it not impact cluster database?

i wish to explain pros and cons to client if we opt this approach.

[balaji.bandi]

Deployed some time back like years back - looks and believe it is the same case 11.X not sure what is the latest 12. or 13.X i guess.

https://www.ciscopress.com/articles/article.asp?p=2743756&seqNum=6#:~:text=Two%20CUCM%20servers%20in%20a,of%2080%20ms%20between%20them.&text=In%20addition%20to%20the%20bandwidth,subscriber%20node%20within%20the%20cluster.

[Nithin Eluvathingal]

If you Don't  meet the requirements, your CUCM data base will not be synced. and if not monitored properly you will end up in major issues. Most commonly faced issue is DB replication. But I have three sites working fine. 

For a deployment where WAN traffic passes  through a Fortgiate we faced  issues with DB replications. Fortigate team finally bypassed voice traffic and that was the solution. 

Read the SRND and Preffered architecture guides and make sure that you meet all requirements mentioned. 

Link for SRND 12 mentioned below, But I couldn't find the 14 SRND. 

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/srnd/collab12/collab12/models.html

[jaheshkhan]

thanks.

But do you think this is the ideal solution.

Will you recommend this method as per your experience? Client will accept based on design what we propose. There is no request from client side to do this way...I dont want to get into trouble later after having lot firewall issues. 

[Nithin Eluvathingal]

I will recommend based on the customer requirement and infrastructure. 

My client in banking sector, they need to have server in both HQ and DR, which we did through clustering through wan. Two Server in HQ and one in DR.

Another petroleum client they had two server In HQ and another two in field. all filed phones register with the field server and HQ phone in HQ CUCM. Even we Did the IM the same way.

But all these customer had a good wan connection to meet the clustering through wan.