OK, heres the deal.
Our company has recently downsized, so I now have an unexpected excess of HP ML350 (single quad core Xeon/4GB RAM/300GB RAID1 SATA drives) and Windows Server 2003 Standard licenses. I also have two free Exchange Server 2003 licenses, as well as sufficient antivirus and backup software to cover all the boxes.
We recently experienced a serious outage where our exchange box, set up by my predecessor, was out of action for an entire day. Recovery could have been made that much swifter but the server was/is also being used as a file server the catch 22 is that I was unable to take the entire system down for recovery until everyone was out of the network shares.
Magnificently, our ISP did not queue any messages during that period where the Exchange box was offline, so not only did our company lose a day of communications, they also appear to have lost a days worth of inbound emails.
As a result of this I have a mission to accomplish:
I want to implement some sort of failover system to keep an email service running in the event of the single Exchange server we currently use throwing a fit.
So, can some sort of redundancy be built in using multiple Exchange servers within one organisation ?
Is there such a thing as an equivalent of Exchange mirroring ?
Is it worth messing around with POP/SMTP accounts as a backup system in the event of Exchange failure ?
Webmail (ISP hosted) as a realistic alternative ?
What I am looking for is some recommendations on a robust system which includes alternatives to a single Exchange box for our organisation.
I am moving our web and mail hosting to a new provider over the next few weeks.
Today and tomorrow I am migrating all user shares off the Exchange server to a new file server I am bringing online so that its only roll is to serve emails, achieving the separation I need.
Where to go from here is the question. I dont necessarily need great detail: just recommendations and sound rationale.