Hexamail - Setting up Sendmail


This section explains how to configure your system if you are running the Sendmail mail server.

Hexamail runs its own SMTP daemon for accepting email. If you are on Unix, you are probably running "Sendmail" (or some other mail server), you will need to decide which method you want to use so that Hexamail can both receive email and forward it to Sendmail.

1) Hexamail FORWARDS TO ANOTHER TCP/IP ADDRESS: assign two TCP/IP addresses to this machine. Tell Sendmail to run on one TCP/IP address and Hexamail runs on the other.

2) Hexamail FORWARDS TO ANOTHER PORT: move Sendmail to another port and inform Hexamail to forward mail to sendmail on the alternate port.

3) Hexamail FORWARDS TO ANOTHER MACHINE: install Hexamail on a machine with no mail server, and inform Hexamail to forward mail to a different machine, which is running your mail server.

Method "1" is the easiest approach. Method "2" is recommended for most sites. Depending on your needs, you may find method "3" acceptable, especially if your mail server cannot have its TCP/IP address or port number redefined.

Forward to Another Address

In this scenario, your machine uses two TCP/IP addresses and has two machine names. Sendmail will run on one TCP/IP address, and receive mail there. Hexamail will run on the other TCP/IP address, and receive mail there.

The advantage of this approach is that it is very straightforward to set up.

For example, if your machine is named "apollo.mycorp.com" and has the TCP/IP address "207.105.6.10", you might also assign your machine the TCP/IP address "207.105.6.11" and have Sendmail listen to that address. Hexamail would listen on the .10 address and forward email to sendmail on the .11 address.

Add a new TCP/IP address

The first step in implementing this method is to obtain, from your network administrator, a second TCP/IP address. A DNS hostname for your second machine is not needed.

The next step is to configure Sendmail to use only one TCP/IP address. If you do not do this, Sendmail will automatically use all the TCP/IP addresses on your machine and none will be available for Hexamail.

To restrict Sendmail to one TCP/IP address, add the following line to the top of your /etc/mail/sendmail.cf file:

Substituting your 1st TCP/IP address for 207.105.6.11. This Sendmail option is explained in the "Options" chapter of the O'Reilly Sendmail book.

You will now need to restart Sendmail. Be sure to telnet to port 25 on each TCP/IP address to ensure that Sendmail is using the correct TCP/IP address.

Configure Hexamail

You will now need to tell Hexamail to use the 1st TCP/IP address. This is done by editing the tcpip.txt file. In this example, the setting would be:

You now need to inform Hexamail to forward mail to your mail server, which is running on the other TCP/IP address. This is done by editing the smtpserv.txt file. In this example, the setting would be:

Change your DNS settings to point to Hexamail

You will now need to change your corporate DNS setup so that mail is no longer sent directly to your mail server, but is instead sent to Hexamail. If you do not know about DNS, you will need help from your system administrator.

For example, if your company is named "yourcompany.com", and now receives mail at "mail.yourcompany.com", you would change this from this:

to this:

You are now ready to use Hexamail!

You can start Hexamail in the foreground with the command "shield start".

Adding a TCP/IP Address

Adding a TCP/IP address on Windows 95/NT

Go to the Control Panel, Click on Networks, Click on Protocols, Click on TCP/IP, Click on Advanced, and you will see a list of TCP/IP addresses. You can add additional TCP/IP addresses on this screen.

Adding a TCP/IP address on Solaris

You can add this TCP/IP address to your Solaris system with a command such as this:

In this example, the Ethernet adapter "le0" has been assigned a second address (with the ":1") of "207.105.6.11" and is now up. You might want to add this command to a startup file, such as /etc/rc2.d/S72inetsvc so that this command executes automatically at system startup.

Forward to Another Port

The first step is to configure Sendmail to listen to another TCP/IP port. If you do not do this, Sendmail will automatically listen to port 25, which will conflict with Hexamail.

To have Sendmail listen to another TCP/IP port, add the following line to the top of your /etc/mail/sendmail.cf file:

This Sendmail option is explained in the "Options" chapter of the O'Reilly Sendmail book.

You will now need to restart Sendmail. Be sure to telnet to port 25 and port 26 to ensure that Sendmail is using the correct TCP/IP address.

You now need to inform Hexamail to forward mail to your mail server, which is running on the other TCP/IP port. This is done by editing the smtpserv.txt file. In this example, the setting would be:

You are now ready to use Hexamail!

You can start Hexamail in the foreground with the command "shield start".

If you are running Unix, you can run Hexamail in the background with "shield -bd". On Windows NT, you can run Hexamail as a service. See Command-Line Options.

Initially, we recommend that you run Hexamail in the foreground, so that any error messages are immediately displayed.