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Exchange 2010 CAS Array with NLB and ESXi


I have built an Exchange 2010 environment in ESXi 4 with two servers (EXCH01 and EXCH02).  I have a DAG setup with these two servers to ensure fault tolerance on the database, but I would also like to implement a CAS Array to ensure fault tolerance on the client side as well.

I followed these articles and was able to get CAS01 and CAS02 setup with NLB.

It appeared to work just fine for OWA access, but my outlook clients could not connect.  I did set the -RPCClientAccessServer attribute to be my FQDN (the same used for OWA).

My questions are...
1) Has anyone been able to get this working in a fully virtualized environment?

2) Can I simply disable Outlook Anywhere on EXCH01 and EXCH02 to test the CAS array?

3) What other items should I check to see why this will not work?

Thanks in advance for the help.

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Well lets start with does anyone have Exchange 2010 setup with a CAS Array?
yep . i've done it with many times and it works fine , virtualized environment does not differ from physical
so you have 2 servers HUB/CAS/MBX roles installed ? and you have done cas array ? am i right ???


Yes, I have 4 VMs. With Exchange 2010.

CAS01 - Just the CAS role Installed with the CAS array setup (and I have a specific IP for the array).  My SSL certificate is installed on this server and a copy on CAS02 as well.

CAS02 - Just the CAS role installed and part of CAS array.  This VM is on a separate VM host for redundancy.

EXCH01 - All roles installed right now.  DAG is working with EXCH02 as a backup server on another VM host server.  When testing I disabled outlook anywhere on this server and made the necessary firewall changes to direct incoming requests to the CAS array.

EXCH02 - All roles installed right now and part of the DAG.This VM is on a separate VM host for redundancy.  This server is really my hot standby.  Of course this would have to be a manual switch over.

I would like to be able to have redundancy on both the client access side (RPC/HTTPS primarily and some OWA access) to match up with my existing database redundancy.

Thank you in advance for your help!
you said you installed all roles on EXCH01 , 02  , is this includes CAS on them ?


Yes.  This correct.  This is a live environment so I want to prove the CAS array works before removing the role from EXCH01.  Is this not possible?  Do I have to remove the role to get everthing to function?
you should remove CAS from EXCH01 , 02