Question : Can I mirror two exchange servers in different sites so they both have same mailboxes?

Is it possible to have two exchange servers in two different sites that both contain the same mailbox data and can both be accessible at the same time? I have two sites with two different Exchange Servers now.

I am implementing a Cisco VOIP system which has a single Cisco Unity Voicemail server in Site 1.

Unity needs all mailboxes to be in the local site(Site 1). But users in Site 2 need to be able to access there mailboxes locally also for performance issues.

So I am wondering if I can move all mailboxes to Site 1 for the Cisco Unity Voicemail requirement and mirror the server in Site 2 for local Outlook access.

Site 1 and Site 2 connected by site to site VPN over T1.

Answer : Can I mirror two exchange servers in different sites so they both have same mailboxes?

"Is it possible to have two exchange servers in two different sites that both contain the same mailbox data and can both be accessible at the same time?"

No.

Exchange 2007 provides some redundancy options but none that will do what you want.

LCR is on the same box.
CCR is on the LAN with a high speed (think gig) connection
SCR is for a standby copy.