microsoft exchange

[cyanide]

I have a domain (domain.com) which needs to have mail forward to Exchange (domain.somedns.com)

Has anyone modified their mx entry of a domain to forward to a Microsoft Exchange server?
The Exchange is sitting on a sub-domain which is pointing to the Ip address of the ISP.
Unfortunately the ISP is blocking port 25, but Exchange is working on port 26.

I have Exim running on port 25 and 26

Besides entering the sub-domain as the mx entry... anything else that needs to be done?

Geez... did that make any sense?

[haze]

If you are sure you have the dns ( mx ) set up correctly, add the domain to /etc/remotedomains and run /scripts/mailperm

[nickn]

Test it with :

exim -bt email@domain.com

It'll tell you where it "would" send the email too, make sure that's the subdomain you setup, if not, you did something wrong.

[cyanide]

Thanks very much for your responses !

Inside the etc/ folder there is no remotedomains file. So, I assume I can just create it?
Also, I heard that I should remove domain.com from /etc/localdomains also. Is this correct?

As a side note, when I run a dnsstuff.com report, everything seems normal, the mx points to this exchange server, but down where it shows the Connect to mail servers, I'm getting FAIL - So I assume this is related?

[nickn]

When you add it to /etc/remotedomains and run /scripts/mailperm it will remove it from /etc/localdomains

You can remove it manaully if you wish

I'm not sure about the other question, not quite understanding the question.

[SarcNBit]

The real issue is going to be with configuring cpanel to send mail to the exchange server on the non-standard port 26. I have not tried this.

Setting exim up to listen on ports 25 and 26 is not the same as setting up to send on ports 25 and 26.

[nickn]

The real issue is going to be with configuring cpanel to send mail to the exchange server on the non-standard port 26. I have not tried this.

Setting exim up to listen on ports 25 and 26 is not the same as setting up to send on ports 25 and 26.

The server won't do the sending, the user will modify the MX records only and the sending servers wherever they are will do the sending. Port 25 will have to be open as well as port 26, but that won't be done by cPanel that'll be done by the sending servers, cpanel will only be handling the DNS / MX records. "Where do I send email for domain.com?" "DNS Server responds please send to mail.domain.com"

[chirpy]

Yup, having SMTP send on any port other that 25 is a non-starter for the reasons nickn gave. SMTP traffic travels between SMTP servers on port 25.

An alternative, is to put everything back to the way it was, and for your client to use something like EFS as a front-end to their Exchange server:
http://www.chimera.co.nz/

[SarcNBit]

Microsoft offers POP3 connectors for Exchange. There is also a POP3 connector inside of GFI Mail Essentials (<- I recommend GFI for all non-clustered Exchange servers).

When I mentioned configuring your server, I was implying that the mail transfer would be handled differently (as it would be if you used a POP3 connector as chirpy suggested). nickn and chirpy are correct that if you simply relied on hosting an MX that pointed to the Exchange server, that sending MTAs would attempt to connect via port 25 and if that port was closed that the delivery would fail. I was suggesting that you would have to accept the mail on your server via port 25 and then relay the mail onto the Exchange server via a different port.

I would suggest that your client either; discuss the matter with their ISP and have them open the port (some ISPs will do this on a client by client basis, especially if the clients are registered businesses), find a new ISP, use a mail relay service like MailHop Relay from DynDNS, or use a POP3 connector for Exchange.

[cyanide]

Thanks everyone for your responses.

I've been doing the email test from dnsstuff.com and keep getting a mail server timeout from the Exchange Server address.

So, it looks like I won't be able to do it through port 26 directly from the server without one of the third-party forwarding programs mentioned above.

[SarcNBit]

So, it looks like I won't be able to do it through port 26 directly from the server without one of the third-party forwarding programs mentioned above.

Please do not misunderstand. None of the 3rd party programs or services mentioned will allow YOU to do it, and in fact none of them besides the MailHop service I mentioned will send the mail on port 26 (if that is in fact the port you configure MailHop to use). In the case of the POP3 connectors for Exchange, you would recieve all of the mail for your client into a catch-all account as you could for any other account on your server without email addresses configured on the cpanel server. You would then configure the connector on the Exchange side to connect to your server and retrieve the mail (similar to the way you would connect an Outlook client to a POP3 mailbox). Exchange would then handle (or not) the distribution for the mail into individual accounts. This traffic would not travel on port 26.

If possible however I would use the POP connector as a last resort. I would try to avoid POP whenever possible. The SMTP protocol is much better suited for mail delivery IMO. In lieu of reconfiguring your server, I would suggest to the client (depending on your relationship) that they either talk to their ISP, change ISPs or use a MailHop like service.

This is really a netadmin/sysadmin issue on your clients side and really has nothing to do with mail or dns hosting. They need to decide how to integrate their network with the rest of the world.

[cyanide]

Thanks very much SarcNBit, for your extended explaination.

I'll pass this on to the client. Initially he was going to use Zone Edit to accomplish this, but preferred to go through the server where his domain is located.

[cyanide]

Actually, any chance this can work on a Windows Machine ?
We're looking at setting up Windows 2003 server with Plesk

[SarcNBit]

Actually, any chance this can work on a Windows Machine ?
We're looking at setting up Windows 2003 server with Plesk

Please explain the 'this' in 'any chance this can work on a Windows Machine'.