Hi,
I have got a problem with my sendmail daemon on a cobalt 5.0 system.
Sendmail version is: sendmail-8.9.3-C7
The daemon has stopped accepting incoming email from other mx hosts. netstat shows a lot of connections (ESTABLISHED & CLOSE_WAIT) from other hosts, but the daemon does not exchange any data with the hosts. When I telnet to port 25, the TCP connection is opened, but there is no welcome message from the server and it does not respond to the HELO command.
I believe having that much connections in CLOSE_WAIT status means that the daemon is not talking to the hosts at all, and the hosts remain in this status after they try to close the connection.
maillog shows entries like this:
Sep 25 00:22:06 www sendmail[26121]: NOQUEUE: SYSERR: putoutmsg (mta4.realage.com): error on output channel sending "220
www.MYHOST.net ESMTP Sendmail 8.9.3/8.9.3; Thu, 25 Sep 2003 00:22:06 +0330": Broken pipe
Sep 25 00:22:06 www sendmail[26121]: NOQUEUE: Null connection from mta4.realage.com [209.75.40.47]
Please advice me. I'm stuck. The owner of the server says that this problem has happened suddenly.