IP changed 2

[benam5]

Hi all,
I have an Exchange server and I want to install AntiSpam on separate server to filter the emails even they hit the Exchange server. In order to install this, I have to make a change of MX Record and the email server will be down for 48-72 hours which I really don't want to do. My question is: if I get the IP address of the current email server and put on the server where the antispam software will be on, would it work? If it does, how long do I have to wait for it to be effective?

If you know a better way to this, please show me.

Thanks.
Linh

 

[ChrisAC]

If you plan it right you can get your MX changed and have it fully propagate within ten minutes.

A week before the change get your ISP to lower the TTL on your MX record to 600 (seconds). After a week all DNS servers around the world with your MX record cached will only cache the record for ten minutes before going back to the authoratative server. You can then change the MX record and the new address will be seen by everyone after a maximum of ten minutes.

Chris.

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

 

[benam5]

Thank you for your reponse, Chris. So my question is if I only take out the IP of the current email server and put it to the new server, would that affect the MX record?

Thanks, Linh

 

[ChrisAC]

If you set the Antispam server up with the IP address of the Exchange server (and give the Exchange server a new address) then you will not need to change the MX record. All mail will be directed to the same address which will then be the Antispam server which can scan the mails before forwarding them to Exchange.

Chris.


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

 

[criticalUpdate]

Is your mail server using the real world IP ?

Jeff

 

[GlenJohnson]

iproute strikes again. Good call. (I'm gonna have to study up on my mail servers.)

Glen A. Johnson
If you're from Northern Illinois/Southern Wisconsin feel free to join the Tek-Tips in Chicago, Illinois Forum.
TTinChicago
Johnson Computers

 

[netometer]

Hi!
Is your mail server behind a firewall?
If so, probably you translate port25\publicIP (specified in MX record) to port25\PrivateIP (the internal IP of your mail server)
I think it would be easier to change the translation to the private IP of your Mail Gateway (the antispam server)
Changing the IP address as iproute suggests should also work but you have to be carefull with your virtual servers on the exchange. By default they use as IP address "All Unasigned". If yoou have changed this setting for some of them you have to switch to the default.

NetoMeter

http://www.netometer.net

 

[benam5]

Thank you all for your help.