Fri Jul 23 09:03:46 PDT 2004

Ran into some issues with aol.com and others blocking email from dynamic IP addresses on my Verizon business DSL account. This is a very bad thing, but fortunately, there’s a reasonable workaround. The solution is to relay the mail through a static-ip machine, and verizon provides one: outgoing.verizon.net. So for a linux sendmail configuration, add the line:

define(SMART_HOST,outgoing.verizon.net)

to your /etc/mail/sendmail.mc (assuming your layout is something like a redhat or fedora box) and then, this is the critical part, you need to authenticate to outgoing.verizon.net as described by "Benway" in this thread:

http://www.webservertalk.com/archive58-2004-6-260816.html —————————————————————————— My memory is a bit hazy on this but, try adding the following line to /etc/mail/access:

AuthInfo:smtp.server.com "U:username" "I:username" "P:password" "M:PLAIN"

Changing the server name, username and password to that of your account. Then run make all in /etc/mail. This will tell sendmail to always send this info by default.

You can test the above manually by uuencoding the details with:

[root@host1 root]# echo -en "usernamex00usernamex00password" | uuencode -m /dev/stdout begin-base64 644 /dev/stdout dXNlcm5hbWUAdXNlcm5hbWUAcGFzc3dvcmQ= ====

Then once you’ve telnet’ed onto port 25 of the mailserver and issued a helo do:

AUTH PLAIN dXNlcm5hbWUAdXNlcm5hbWUAcGFzc3dvcmQ= ——————————————————————————

If you are on a redhat/fedora machine you can restart sendmail as follows and it automagically updates the config files

/sbin/service sendmail restart

This appears to have solved the problem for me as I’m not getting mail from aol.com and other addresses bounced back to me. So Benway, whoever you are, thank you very much for the helpful information!