I've been trying to install Exchange 2010 SP3 for the past 5 hours and it appears as though the job is stuck on the "Mailbox Role" portion.
The server holds the CAS, HT and ET roles and had SP2 installed previously (no update rollups). The .edb file is about 310 GB on a VMWare box with 24 GB of RAM on a RAID 10 so it should be plenty fast.
All of the previous roles went quite fast but the Mailbox role has been about halfway through for 7 1/2 hours now. Occasionally the progress bar will flicker but it hasn't made any progress in that time.
Is this normal behavior? I'm not sure if the job is stuck or if Exchange is actually processing things. If the job is stuck is there any way to safely abort the installation?