vbulletin mail sending
 

Hi, I am setting up a new server with a hardware firewall in front of it using NAT

I am trying to lock down as many ports as possible

I have no reason that I would want email to be delivered to my domain -- but I want my domain to be able to send mail (for example, vbulletin notification messages)

would i be correct that this means there is no reason to open port 25 , 110, 143 on the firewall from the outside?

is there any potential problem that could arise from disallowing messages to be send to my domain?

thanks

How do you want to handle bounced emails?

couldn't i just not do anything?

Sure, but you will be sending out a lot of emails to non-existing accounts. Those will come back to your server. If they cant reach the server, then I expect that your site would quickly be blacklisted as a spammer, which in turn results in many email providers blocking your emails.