Here's our current setup:
– Firewall with SMTP proxy, scans incoming/outgoing mail and forwards to Exchange2010 server
– Internal Exchange 2010 server (SP3 RU11), running Sophos PureMessage as Exchange AV software
We'd like to upgrade to 2016 in a short time (skipping 2013), however it seems the PureMessage software won't be "certified" for Exchange 2016 somewhere in Q2 of 2016. I don't really want to run it without PureMessage cause it happens sometimes that virus/spam mails still get through our firewall SMTP proxy but then luckily are detected by PureMessage.
So here's my question: Can I leave my Exchange 2010 server in place and keep forwarding mails from the SMTP proxy to 2010, while moving all my mailboxes to my 2016 server, so as to keep my PureMessage checks on incoming mail on the 2010 server and still benefit from the new Exchange 2016 features for Outlook on the web, etc.? I suppose the 2010 server will know to which server it has to deliver the mails?
Thanks a lot for any recommendations.
Michiel.
Best Answer
Exchange 2016 can co-exist with Exchange 2010/2013 better than previous versions of Exchange; however, I don't believe "up-proxy" from Exchange 2010 CAS -> Mailbox (MBX) on Exchange 2016 will work.
From all the documentation I've seen, it seems up-proxy is only supported from 2013 to 2016 and not 2010 to 2016.
Down-proxy (Exchange 2016 MBX -> Exchange 2010) works just as co-existence worked in an Exchange 2010/2013 environment.