For about 6 months, I've had two lines coming into my house. AT&T (Uverse) for TV, phone, and internet, and Comcast Internet Only (had a great deal on it). Comcast recently jacked up the rate due to a promotion ending, and I don't want to pay 65$ a month plus the 200 something for AT&T, so I'm dropping Comcast. I have a number of machines on my network, that I've switched over to the AT&T line (just plugged the router they were connected to to the AT&T box). and now I find that I'm having trouble sending email from Exchange.
Before when I was on comcast, I had no issues sending/receiving from Exchange to gmail, yahoo, etc. The moment I swapped the line, I could only receive, but not send. I did some research and saw that it looks like AT&T Uverse blocks SMTP traffic, so I called up AT&T and first got the Philippines, which was no help, then I got someone in India, who didn't even know what Exchange was. They claim they don't block any ports (except neither could tell me what port SMTP ran on), yet when I try doing some basic tests, I get failures.
Here's what I know:
1.) So far, can only successfully send to the AT&T account they set up. Gmail, my work email, yahoo...nothing else works. No problem receiving inbound email though
2.) nslookup for gmail:
C:\Users\Administrator>nslookup -query=mx gmail.com Server: www.asusnetwork.net Address: 192.168.0.1 Non-authoritative answer: gmail.com MX preference = 5, mail exchanger = gmail-smtp-in.l.google.com gmail.com MX preference = 20, mail exchanger = alt2.gmail-smtp-in.l.google.com gmail.com MX preference = 10, mail exchanger = alt1.gmail-smtp-in.l.google.com gmail.com MX preference = 30, mail exchanger = alt3.gmail-smtp-in.l.google.com gmail.com MX preference = 40, mail exchanger = alt4.gmail-smtp-in.l.google.com
If I ping these, i get a reply, but if I try to telnet to any of them against port 25, I get timeouts.
telnet smtp.gmail.com 25 Connecting to smtp.gmail.com...Could not open connection to the host, on port 25: Connect failed
So I try using one of AT&T's servers
telnet frf-mailrelay.att.net 25 220 att.net - -Maillennium ESMTP/MULTIBOX frfwmxc14 #1036
I then try SMTPS on gmail:
telnet smtp.gmail.com 587 220 mx.google.com ESMTP g1sm2482249oeq.6 - gsmtp
so SMTPS works fine, but not SMTP. telneting to smtp.gmail.com 465 also seems to connect, but gives me a blank screen
Last but not least, I grab a vm thats running ubuntu behind the AT&T box, and run tcptraceroute. results:
evan@apt-proxy:~$ sudo tcptraceroute smtp.gmail.com 25 Selected device eth0, address 192.168.0.113, port 56215 for outgoing packets Tracing the path to smtp.gmail.com (22.214.171.124) on TCP port 25 (smtp), 30 hops max 1 192.168.0.1 0.431 ms 0.340 ms 0.376 ms 2 192.168.1.254 1.484 ms 0.901 ms 0.703 ms 3 * * * 4 * * *..... (and so forth)
so it's clear that it dies right outside the 2Wire box from AT&T.
Besides this, is there anything ELSE i can try to get more evidence against at&t? I found this link http://forums.att.co...ed/td-p/2544419 that seems to help, but the links to the at&t social media connect guys doesn't work. I'm just looking for any more tests I can do to prove AT&T is blocking port 25 outbound.