one of customers have single Exchange 2007 SP1 Server with Rollup3, they decided to build high availabilty with SCC (2 nodes), 2 load balanced CAS/HUB..the 4 servers will be updated with Rollup9 but the old single server will contniue with Rollup3 till moving all mailboxes & PF contents then it will be decommissioned...so my question is it supported to have 4 servers with Rollup 9 & one with Rollup 3, will the enviornment be affected with issues..

HI, Due to some performance and reliability issuses, dosent recommends building cluster with different rollups. Theoretically it will work but you mightbe facing some strange problems.BTW: is there any problem toinstall rollup 9 on old server?Regards TheoreticallyChinthaka

Dear,the cluster nodes are both Rollup 9, my question in another way, can i have single Server with all roles (CAS,HUB,MBX) running EX2007 SP1 Rollup3, then build new SCC with 2 nodes running Ex2007sp1 Rollup9, 2 CAS/HUB with Rollup9...after that i will start moving mailboxes from the old server to the new cluster. then decommission the old server..are there any issues?? is there any article??the customer refused to install Rollup9 in old server since they don't have testing enviornment & insist to build the new Env with Rollup 9 then start moving resources..

any update..

~ Different rollups can exists on different Exchange servers in same org but NOT recommended. ~ Recommendedsequence to update the servers is CAS, Hub, Mailbox and Unified Messaging so I would say update the single server which holds all roles to UR9. ~ It is also recommended to keep all servers of any role at same level of Update Rollup. eg. update all CAS servers first, update all Hub servers, update all mailbox servers but you have many roles running on a servers so doesn't apply... Also if you get any issue during building SCC & 2 CAS/HUB and log a call to PSS, then they will also recommend to update the single server from UR3 to UR9 first and check the issue... Amit Tank | MVP Exchange Server | MCITP: EMA | MCSA: M | http://ExchangeShare.WordPress.com

Thanks Mr. Amit, you are 100% right, PSS surely will ask for ROLLUP 9 in old server..i will say the same to customer