SMTP/Relay and OWA on same server

[seands]

Hi everyone

Would like some advice on which is best?

I'm setting up a SMTP/Relay server in our DMZ, which will have mail.companyname.com asigned to it with our ISP's DNS server. I'm also setting up a OWA server to, but would like to know if its a good idea to set this up on the same server. Or should I setup OWA in a different DMZ on different server?

What would be nice though is when someone wants to access there email from outside world, they type in mail.companyname.com to access OWA.

Thanks
S

 

[NETING]

Good question...Just did this recently.

Assuming your ISP hosts your DNS zone file for companyname.com ( the company you work for)have them change the MX entry. Without causing any downtime this is what you can do. Have them add another MX record into your DNS zone file with the name relay.companyname.com ..or whatever name you want.. nating to what ever the relay servers public address is. In this case let's say 63.x.x.100. Remember you will have an MX record in your DNS zone file as it is which is mail.companyname.com nating to public IP address 63.x.x.100. Now you will have two MX entries in your zone file with different names, nating or translating to the same public ip address. The key is to give the new mx entry in the zone file with the name of relay.company.com a lower number in the DNS Zone file. The lower the number alloted to the MX record, this will be the first to be checked when someone is sending mail to you. By doing this, mail going through the relay server from the outside will look at the lower number MX record entry which should be the new one youjust added. Until the DNS resolution takes place, mail from the outside world will use mail.companyname.com until the new entry is viewable by the world. Remember inorder to free up mail.company.com you must allow for DNS to resolve to the world. It is best to wait anywhere from 48 to 72 hours before it will start using the new MX record. Then you can ask your ISP to remove mail.companyname.com. Please make sure first to verify mail is using the MX entry with the lower number. This will assure you this gets first priority. Hope you understand...Then I would set OWA on a different server and give that mail.companyname.com. I like the fact of keeping these two on different servers just because of the importance of your relay server. It also lets you use the name for what you want. DNS zone file examplebelow.

current
mail.companyname.com IN MX 10

after entry to dns zone file
relay.companyname.com IN MX 5
mail.companyname.com IN MX 10

after resolution have them remove mail.companyname.com
relay.companyname.com IN MX 5

You then have to add A records but your ISP should be able to help you with this. Hope this helps.