Hi All
I'm looking for a bit of advice as to the best method to migrate from Exch 2010 to 2013. Basically I cannot have any BES outage at all, I know I need to build a new BES server for Exch 2013 mailboxes with all the patches and new CDO/MAPI etc etc
What I'm confussed about is the BESAdmin account that resides on 2010, I know I need to move it to 2013 but what happens if the mailbox migration is phased? If I move the besadmin to exch 2013 mailbox will it still work on exch 2010 and also 2013? should I create BesAdmin2 for Exch2013 only and leave BesAdmin on 2010?
The environment is quite complex with over 1000 mailboxes and around 700 BB Users, so we cannot do it one weekend and be done with it, migration will be over a few weeks, so will be running co-existence exchange 2010 and 2013 together for around 2 months until we decommission.
Has anyone done this type of migration before - must be someone, but I just cannot find anything online that answers my questions.
Any help would be much appreciated.
Many Thanks