SMTP Relay when Server is Offline??

[Sparks48]

Hello,

My office is moving to a new building and I need to setup a form of SMTP mail bagging while the server is down for like two days. I am planning on building another Exchange Server with an IMS give it a cost of 20 on DNS for MX record and when my main Exchange goes down, mail will hit my stand in server and the mail will build up until I bring up the main Exchange server. Does my theory work or will the messages hit the IMS wait for day and then ship off an NDR. Basically I need to bag all incoming SMTP mail while I am moving my production Exchange Server.

Thank you,

Phil

 

[dmandell]

Most ISPs provide mail relay services as part of the package. (many people don't even know or bother to use it) Find out if they are and have an MX record created for their server, if it's not already there. This may save you a lot of effort in having to build a new servers, etc.

Most people's outbound is set to try from 4 hours to 5 days if the server is not found) I would try to shoot for a downtime of no more than half a day to reduce the possibility of returned mail.

(It's worth it even if you have to move the server yourself in the back seat of your car!

 

[Sparks48]

Thanks for the info. I see how on the Connections Tab within the IMS I can specify the times. The defaults that ship with Exchange don't match up with the timeouts. What is the best way to reset this.

 

[dmandell]

You probably don't have any control on the timeout settings of your ISP, but the settings on your exchange server (connections tab) deal with mail coming from your internal users and going outbound so that won't help you much.

On the timeouts dialog
The top timeout settings are how long your server will try to send an outbound message before giving up.

The lower settings
deal with notifying your users (the sender) if a message fails to be sent.

So if you were to assume that most of the servers that are sending you mail are Exchange servers with defaults, (This is of course an absurd assumption) a normal message would attempt to be sent to your users for 2 days before giving up. So your server could in theory be offline for two days with no mail loss. Most Linux/Unix Sendmail servers default to a generous 5 days (if not changed from default)

(But the people trying to send you mail while your server is down will get error messages from their servers aprox. every 4-12 hours depending on the settings.

I hope this is the info for which you were looking.
Dana