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Ok, I feel like a dork. I know this has got to be a really easy issue,
but I sure can't seem to find it.

New install of Fedora core 1. yum updated all the packages (incl.

modified and changed
DAEMON_OPTIONS(`Port=smtp,Addr=, Name=MTA')dnl
dnl # DAEMON_OPTIONS(`Port=smtp,Addr=, Name=MTA')dnl

did the make -C /etc/mail

can issue "telnet localhost 25" and get a response as one would expect.
However, nothing is coming in. Telnet to the host from elsewhere (even different computer using same switch - not a firewall issue) using port 25 goes unanswered.
nmap localhost shows "25/tcp open smtp"

http and ssh to the machine are working fine

What am I missing?
what does:

netstat -an | grep 25 | grep LISTEN | grep tcp

Mine says:

tcp 0 0* LISTEN
I think the command you want to use to update is this (from within the /etc/mail directory):

m4 >

In order to do that, you will need the following packages installed:

that netstat command on my box shows the same result.
I issued the m4 command as shown, restarted sendmail, but still nothing.

Anything else I can try?

your /etc/hosts file should looks something like this localhost.localdomain localhost

Robert B
It (/etc/hosts) does. I also have /etc/host.allow with
sendmail: ALL

Someone suggested doing a tcpdump while trying to telnet to the box on port 25. Here is the output of that:

[root@cornerstone etc]# tcpdump host cornerstone and titan
tcpdump: listening on eth0
11:29:50.870754 titan.42321 > cornerstone.smtp: S 886781666:886781666(0) win 5840 <mss 1460,sackOK,timestamp 41904123 0,nop,wscale 0> (DF) [tos 0x10]
11:29:50.870856 arp who-has titan. tell cornerstone
11:29:50.870984 arp reply titan. is-at 0:7:e9:d:5f:66
11:29:50.870999 > titan: icmp: host cornerstone unreachable - admin prohibited [tos 0xd0]
Ok, I just found my own answer. The file I needed to modify was /etc/sysconfig/iptables. I had to add the smtp, imap, & pop ports to those that are open.

As soon as I did that, everything worked.
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