We were running two Exchange 2007 CAS load balanced by F5(BigIP Load balancer) plus two HUB and a CCR Cluster in same AD site called Site1. Because of organization movement to new location we moved one CAS server to new location which have totally new AD site called Site2. Both sites have full internet connectivity. Also the F5 load balancer is moved to Site2 form Site1. Now the problem if we keep running with one CAS server which is in Site1 with all active mailbox servers, everything works ok. But the moment we include newly moved CAS (Site2) in F5 Server pool, users start getting error messages in OWA like "For best performance you should be using this url: https://site1.contoso.com" Evet viewer on Site2 CAS is showing following error messages: "CAS server CAS01 failed to proxy EWS to AD site CN=Site1 because none of the CAS servers in this site are responding. Please check the configuration and status of the servers in site CN=Site1" What can be the issue, I want to both CAS servers should be working through F5 load balancer even though both are residing in different AD sites? Note: All subnets are properly mapped to relevant AD sites.

Why is there a CAS in a Site with no mailboxes? I Dont think you can do what you want regardless. Exchange is doing what its supposed to do. If the ultimate plan is to have redundant internet-facing CAS and Mailboxes in each AD site, then you'll need load-balancing and at least 2 CAS in each AD site.

Why is there a CAS in a Site with no mailboxes? I Dont think you can do what you want regardless. Exchange is doing what its supposed to do. If the ultimate plan is to have redundant internet-facing CAS and Mailboxes in each AD site, then you'll need load-balancing and at least 2 CAS in each AD site. I agree with your answer. We are doing this for moving our servers to new Data Center, I mean we are trying to do in stages like just first move one server from CAS and HUB and then move remaining CAS and HUB and at last move mailbox servers to new Data Center which is part of AD Site2. What are your recommendations to achieve above goal with a minimum possible down time?

Hi, Only thing you can do is to move the servers in one big bang (or maybe configure both datacenters to be in the same AD site) For the CAS server to work you would need to configure the CAS in the original site to work as if it was not internet facing which you probably don't want. If you move a HUB server this won't be used for mail submission as only HUB servers in the same site can be used for that. Leif

On Sun, 3 Jul 2011 13:30:01 +0000, Manajee wrote: > > >Why is there a CAS in a Site with no mailboxes? > >I Dont think you can do what you want regardless. Exchange is doing what its supposed to do. > >If the ultimate plan is to have redundant internet-facing CAS and Mailboxes in each AD site, then you'll need load-balancing and at least 2 CAS in each AD site. > >I agree with your answer. We are doing this for moving our servers to new Data Center, I mean we are trying to do in stages like just first move one server from CAS and HUB and then move remaining CAS and HUB and at last move mailbox servers to new Data Center which is part of AD Site2. > >What are your recommendations to achieve above goal with a minimum possible down time? Create a new subnet for the CAS server at the other data center and add that subnet to the AD site "Site1". --- Rich Matheisen MCSE+I, Exchange MVP --- Rich Matheisen MCSE+I, Exchange MVP