Let me start by giving you our current Exchange setup. We have Exchange 2007 with 2 CAS/HUB servers and 2 Mailbox Servers in a CCR cluster all are physical hardware servers. We have approximately 150 mailboxes in use by users and distribution groups.
My organization is upgrading to Exchange 2013 on a virtualalized server. Originally my idea was to do a side by side migration of Exchange 2007 to Exchange 2013. After doing some research, I was able to get the 2 CAS/HUB servers updated to SP3 RU10, which is required for side by side migration. However when I tried to update the clustered mailbox servers I ran into an IIS issue in MS Server 2003 and have been unable to resolve that issue.
As an alternate solution I planned to see if we can just bring down the clustered mailbox servers, bring up our new Exchange 2013 mailbox server, and then import the mailbox databases from Exchange 2007 into our new Exchange 2013.
Is this possible or should I look into other solutions to this dilemma?