Hello all. I have a Linux box running FC2. Running Sendmail 8.12.11. My server seems to be functioning correctly except for a few small issues. When it tries to connect to two different servers, the connection times out. This did not start until 2-3 days ago. Before that everything was fine - clients could send mail successfully to that address. Now it just times out. This started about the time that I began to subscribe to a spam blacklist. I thought it might be a slow response by the blacklist making the servers timeout before it could respond so I commented out those lines and rebuilt the sendmail.cf file. Still no joy. Mail still times out. I get no errors, no comments and the mail log says that the "connection timed out with XXX.XXX.com. Nothing else. So my theory about the spam blacklist taking too long to answer didn't do the trick. If anyone has any ideas on how I can test to make sure it isn't something on my end I would appreciate it. Thanks in advance for any and all help!

P.S. - I can't communicate this problem to the admins on the other end as they are "untouchable". One is Microsoft and the other is Walmart. Any ideas would be appreciated.

You can check the remote mailserver by attempting to communicate with it manually:

$ telnet XXXXXX.com 25
Trying 123.45.67.89...
Connected to XXXXXX.com (123.45.67.89).
Escape character is '^]'.
220 XXXXXX.com ESMTP Sendmail 8.13.1/8.12.11; Sat, 15 Oct 2005 12:09:12 -0400
HELO dummy.net
250 XXXXXX.com Hello XXXXXX.com [123.45.67.89], pleased to meet you
quit
221 2.0.0 XXXXXX.com closing connection

If the response is reasonably quick, then the problem isn't the remote server. Is your email server on a dynamic IP? Many folks block email from dynamic IP addresses.

No, the server is on a static IP. Been the same IP for about two years now. I tried connecting to the other server via telnet after I made the post and all I got was a blank screen. No response or anything. One thing that I forgot to post is that I can send mail from an external account (i.e., yahoo) to one of those accounts but nothing can get through from mine. I would have thought that if they had me blocked for some reason I would have gotten an error message, but nothing. Thanks for the help though! I'll just keep at it and maybe someone will post something that will make a light bulb go on.

Not changing is not the same as static. If the address is defined by your ISP as dynamic, that is how it will be treated.

I run my own dns servers and have a direct pop to alltel (fiber link) and part of a class c set of IP addresses from IANA. I share the addresses with another company; helps with costs. So I would guess that I am my own ISP in this case. The Ip address range is portable (can change from one tier 2 to another) but the address of my mail server is not handed out by a DHCP server (dynamic). They are infact static ip's. At least from everything I have been taught anyway. Any other ideas? This is really hard to troubleshoot when you just can't pick up the phone and call someone on the other end and ask "what's up?". Thanks for your help though and I will hopefully figure something out or someone will post an answer that makes the lightbulb go on.....

Better to verify the address here, and see if it's in anyones database as dynamic or blocked.

Nope. Not listed there either. I usually use http://www.dnsstuff.com for that kind of lookup. But it wasn't listed there either. That was actually the first thing that I thought about. If a server ends up on a list you block them. But if it does get blocked, there is usually an error message that states so. I never get any error messages from these two servers, just time outs.

If you're not blocked, then you may be able to get more information with the telnet test in post #2. The destination servers could simply be having a problem (they could be owned, and busy pumping out spam, for example).

If the telnet test times out as well, then the issue is likely on the server side.

Well, when I try and connect via telnet, all I get is a blank screen. For instance, from my desktop (running windows XPPro) I start a command line and type the following: telnet 123.456.789.000 25. The screen changes like I would expect it to and then justs sits there. No apparent response or messages from the server. If I connect to my own server, I get a response, etc. Those just sit there. Could it be that if they are blocking me for some reason, it is at a firewall? That would be unusual for Microsoft (one of the culprits) but not Walmart. They are famous for trying to be secretive. Oh well, any other ideas?

It could be that they're using something like SPF. You can try adding the DNS records and see if they then allow connection. You can use the self publishing wizard at that website to help you create the necessary DNS records.

I haven't heard of that yet but will definitely check it out thanks! I will give that a try and repost. Thanks!