Im in process of migrating from Exchange 2010 server to Exchange 2013 server. I have Installed two Exchange 2013 CAS/MBX in site 1 and Exchange 2013 CAS/MBX in site 2 and I will be configuring the DAG between them. I will be going live before I get my Kemp hardware load balancer.
I need to manage even with one CAS for 1 month until I get my HW load balancer. what is the best way to reduce the downtime while migrating my users from 2010 to 2013. can I have Exchange 2013 CAS and some users still in 2010, will they be able to access?