We have Office Communication Server 2007 (OCS)live and in production here at PointBridge. It is co-existing nicely with Live Communication Server 2005 (LCS). There was only one hang-up at first: LCS users couldn’t see OCS users’ presence. It was a one-way thing though; everyone on OCS could see all the LCS users’ presence no prob. But for the LCS people, anyone who had been migrated to OCS showed up as "status unknown" or "unknown status". This was not cool at all.
It turns out that it the trouble was due to the fact that you are supposed to use a hardware load balancer with OCS Enterprise. Even if you have only a single OCS Front-End server in your pool, you are supposed to have a hardware load balancer in front of it.
The pool has to have its own fqdn (ocspool.company.com) which is different than the server name who belongs to that pool (ocsserver.company.com). And here is the catch: each of those FQDNs must resolve to DIFFERENT IP ADDRESSES! With a hardware load balancer, this is no biggie: the load balancer has an IP that resolves for ocspool.company.com. The server has an IP that resolves for ocsserver.company.com.
But because I didn’t have a hardware load balancer, I just had both FQDNs resolve to the same IP address.
Whilst this didn’t prevent OCS from coming up and functioning in every other way, it did break presence between LCS and OCS. A helpful PSS guy, Kelly Vickers, pointed out the error of my ways. Apparently SIP messages get confused when the pool and server name have the same IP. He also mentioned that having a hardware load balancer is the only supported configuration, even if you have just one server.
However, there is a workaround. Here was my resolution:
1) add a second IP address to the OCS FrontEnd server
2) change the DNS entry for my ocspool to resolve to the front end servers new (secondary) IP address
3) do an ipconfig /flushdns on the OCS and LCS servers
4) restart the OCS front end services
5) have LCS users log on of MOC 2005 and log back in
I have posted this on the MS forums as well, you can follow the thread here:
http://forums.microsoft.com/OCS2007/ShowPost.aspx?PostID=1646092&SiteID=57
Overall, Office Communications Server is working like a champ. We’ve got internal LiveMeetings, voice, and video calls are working internally and externally.
Up next: integration with Cisco CallManager 5.1
