ISP not using 25 due to spam
Please could you inform me how to switch smtp to 587.
ISP (Comcast) told me due to spamming they are not using 25 any longer.
I'm not sure how to go about changing to 587.
ROUTER specification was simply SMTP without a port being specified, which routed to my server box. Not sure if default included 25 and 587, so I deactivated it and added a separate line for smtp routed to port 587 going to my server.
SERVER /etc/services has process called submission on 587 tcp and udp. Can you tell me how to change this? Eliminate the line for smtp 25, and rename 587 lines smtp? Or what should I do here?
I think isptables are OK.
Is there anything else that needs to change?
Thanks in advance for assistance with this.