Smtp cannot establish a remote connection

Mail and Messaging Guide
Chapter 4, Managing mail with MMDF

You can have a working TCP/IP configuration with successful implementation of most TCP/IP functions (telnet, rlogin, ftp, and rcp) between the local machine and a remote machine, but the /usr/mmdf/chans/smtp program may be unable to establish a connection with the remote site.

You may see an error message like this in /usr/mmdf/log/chan.log when you attempt to send mail to the remote site if you have the logging level set to Every diagnostic possible (FTR in the mmdftailor(F) file):

   trying 89.0.0.3
   can't get connection (115)
   [SYSERR(115) connection refused] a3000.sco.com(59000003) no open
   sm_gethostid (a3000.sco.COM)
   tb_k2val (smtp.chn, first=0, a3000.sco.COM)
   tb_k2val failed
   qu_wrply()
   (DHST) 'Remote host unavailable'
   qu_wrec() (15) "Remote host unavailable"
   qu_radr
   qu_rrec ()
   (4) "aend"
   qu_wrply()
   (DHST) 'no valid addresses'
   qu_wrec() (51) "no valid addresses"
   qu_mend
   hd_end ()
   qu_pkend
   wend
   qu_end

When inetd(ADMN) is started it reads /etc/inetd.conf and /etc/services. It then creates a socket for each server and binds each socket to the port for that server.

inetd listens on multiple ports for incoming connection requests. When it receives a request it spawns the appropriate server.

The above error message indicates that the local smtp program did not establish a socket connection. This means that the inetd process on the remote machine did not open a socket for smtp at port 25 because the smtp entry was omitted in /etc/inetd.conf and /etc/services.

To resolve the problem:

Log in as root on the remote machine.
If the smtp entry is missing from /etc/inetd.conf, edit inetd.conf and add this line:
```
   smtp  stream  tcp nowait mmdf /usr/mmdf/chans/smtpd smtpd
   	/usr/mmdf/chans/smtpsrvr smtp
```
NOTE: This long entry is all one line.
If the smtp entry is missing from /etc/services, edit services and add this line:
```
   smtp      25/tcp      mail
```
The line in /etc/services consists of service name, port number and protocol type (separated by /), and an optional alias name.
Restart inetd by entering this when in multiuser mode:
```
   ps -ef | grep inetd
```
If you see an output similar to this:
```
   root  257 1 0  May 11  ?  0:01 inetd
```
then kill inetd by entering:
```
   kill -1 257
```
Where 257 is the process id.

If the remote machine (to which mail is being directed) is not an SCO system, see the appropriate documentation for your system.