Running a second "emergency" mail server in an exchange environment.
Posted on 2008-10-06
I am looking at ways of minimising end user down time in the event of my Exchange 2003 server failing. I am running exchange 2003 enterprise in a single domain with 70 users running outlook 2003. My ISP is demon internet and the email comes to my exchange via SMTP and I send using the demon smart host. If exchange is offline Demon have relay servers that keep trying to send the mail I do not have the option to access this stored mail via a pop account.
The scenario I want to protect against is motherboard/power supply failure - i.e. something that could render the server unoperational for up to 24 hours but would not affect the hard drives so that as soon as it comes back on line exchange will come back to life.
What I need is something that can act as a stop gap during this period. I have a rough idea of what I would like to happen but would be grateful if somebody answer my queries, point out any flaws or suggest any other ideas.
Firstly, i intend to make sure all users have cached exchange mode enabled in outlook so that all users have access to their mail folders if the server goes offline.
Next I would like to have a second mail server preconfigured on my network - something like hmailserver or xmailserver. If the exchange server goes down I can then quickly reconfigure the firewall so that all incoming mail is diverted to the backup server. Users can then get their email either via another client (outlook express or whatever webmail clients the backup mail sever offers) or directly into outlook if possible.
Then once the exchange server is repaired I can change the setting back on the firewall and everybody starts using exchange again.
Can anybody let me know whether my plan is feasible? Can 2 mail servers co-exist on the same domain without fighting with each other?
The area I am really not sure about is how the users will get their email. Is it possible for them to configure outlook to connect to another mail server, download email into their offline mailbox and then when exchange comes back on line have this mail resynched with their exchange mailbox?
Finally, does anybody have any comments of either of the two mailboxes I have mentioned to could suggest any others?