SMTP Relay

[BobSchleicher]

My goal is to setup a recieve connector on my server to allow external users to authenticate using SSL SMTP. I know I would have to open my firewall for that port.
I am very hesitant on doing this. Can someone offer any visible issues (like OMG your crazy or your now a SPAM mule or no issues because your authenticating)?

BobSchleicher

 

[58sniper]

Why aren't your users user RPC over HTTPS (aka "Outlook Anywhere? in Exchange 2010) and talking RPC to the server? That's far more beneficial.

Do you have your Tek-Tips.com Swag? I've got mine!

Stop by the new Tek-Tips group at LinkedIn.

 

[BobSchleicher]

We do have OUR users using that but we are offering a service to some of our customers and basically it works like this:
We ship a PC to their location and a custom application collects alerts and emails these alerts to our company but some of our customers don't want to allow an email relay for that PC to send these alerts to us. So my only thought is to setup a secure SMTP connect with our email server so we can relay these emails to ourselves and the customer won't have to change anything in their environment.
I was originally going to purchase a service from a company but the email alert volume (we get more than a million emails a month just from these alerts) we do makes the cost too high.
Hope this makes more sense now.

BobSchleicher

 

[Zelandakh]

Yes, that is a good clarification.

Create an SMTP receive connector but use TLS instead of SSL, open port 587 to the Exchange server. Then secure the receive connector so that only a single account (SMTP_Alert etc) can use it then configure the PCs application to use that username and password over TLS to connect to the FQDN of the mail server.

That should work and should be reasonably safe.

 

[BobSchleicher]

I do currently have it set like this but my concern now is a SPAM king is going to figure out a domain users name and password combo. Am I too paranoid? Right now I'm thinking about setting up a cheap/free email server that I will create a username and password in that software and then only allow email going to x@domain.com then relay that to my current EX. This may help me only except email from certain domains which I don't think I can do that on a recieve connector (I don't want to block any domains on my default connectors.

BobSchleicher

 

[Zelandakh]

Yup.

Make the username really long and the password even longer...and leave it on your domain.