Additional MX Record/IP Change

[ArtF1]

I'm switching ISPs and want to make the transition as smooth as possible. We currently have 1 MX record that corresponds to an A record that points to the old IP address. I want to add an MX record that directs to the new IP address and uses the same host record. The object is to lose as little mail as possible while making the switch to the new address. Is this "do-able"?

EX:

host IN A ip.address.of.mailserver
IN MX host.domain.com

Any help would be greatly appreciated.

 

[wbg34]

Yes it is doable.
I would setup a mx record for a second mailserver i.e. mail2.domain.com. With a corresponding entry that points to the new ip address.

host.domain.com A ip.address.of.mailserver
host.domain.com MX host.domain.com
host.domain.com MX host2.domain.com
host2.domain.com A new.ip.address.of.mailserver

This will work as long as you are hosting your dns externally or if you will be running both ip's simultaneously. If not, then this really wont help you because it will take time for other dns servers to catch up to your new ip address. Until they catch up they wont be able to resolve your name. I would contact the ISP that I am leaving and have them forward all traffic from my old IP to my new IP for a month. That way your dns should be fine after you update it to reflect the new IP.

 

[ChrisAC]

Lower the TTL on the domain to say 900 (ten minutes). Then when you are ready to switch over to the new service with a new IP address on your server change the MX record to point to the new IP address. It will only take ten minutes to fully propagate.

If you have a backup mail record for mail spooling then you shouldn't loose any mail at all.

Chris.


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Chris Andrew, CCNA, CCSA
chris@iproute.co.uk
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