Using TELNET to Troubleshoot EIMS Server Problems

ISSUE:

How can I troubleshoot EIMS through telnet commands?

SOLUTION:

A very fundamental way to test the various services offered by the EIMS server is through the use of a standard TELNET client. On the Macintosh, common TELNET clients are: NCSA Telnet, Better Telnet, MacTelnet among others. You can also use a TELNET client on a Window/DOS PC, most any UNIX machine and other machines that have Internet facilities. Most of the EIMS services that can be tested communicate with the respective client using a command language. Through the use of a TELNET session you can issue commands using the proper syntax and judge the results you receive to determine whether EIMS is adequately performing that service. These results will often tell you whether the problem is within the EIMS server configuration or that the problem is outside of EIMS in the client, local network or Internet configuration.

The following EIMS services can be tested to some degree using TELNET.

Following the service name is the common EIMS port used for that service.

Admin : 4199

POP3 : 110

IMAP : 143

SMTP : 25

Password : 106

Ph : 105

LDAP : 389

ACAP : 674

The basic information required to establish a TELNET connection to a specific server port is the domain name of the server and the TCP port number.

To initiate a TELNET connection using the command line form (UNIX,Windows) you would issue a command with the following structure:

telnet domainname.com portnumber

In a TELNET client application on the Macintosh this information would be entered into a field labeled Host Name: or Host/Session Name: with the following form:

domainname.com portnumber

EIMS Admin

Since there are no commands that can be issued to test the Admin connection, telneting to port 4199 will serve the purpose of confirming that the EIMS server is available to connections on that port. In the telnet window a positive response would be the display of stream of random characters. If the result is that the connection could not be established this could mean that there is already an Admin connection to this server, the port is unavailable due to blocking by a firewall or there is some other basic connectivity problem.

POP3

The POP3 service uses a fairly basic set of commands that need to be issued in a certain sequence. Below is a link to a web page that will supply more detailed information about the POP3 Internet standard and the POP3 command structure.

http://freesoft.org/CIE/RFC/1725/index.htm

Minimal POP3 Commands:

USER name valid in the AUTHORIZATION state

PASS string

QUIT

STAT valid in the TRANSACTION state

LIST [msg]

RETR msg

DELE msg

NOOP

RSET

QUIT valid in the UPDATE state

Optional POP3 Commands:

APOP name digest valid in the AUTHORIZATION state

TOP msg n valid in the TRANSACTION state

UIDL [msg]

POP3 Replies:

+OK

-ERR

Note that with the exception of the STAT, LIST, and UIDL commands, the reply given by the POP3 server to any command is significant only to "+OK" and "-ERR". Any text occurring after this reply may be ignored by the client.

IMAP

Telneting to port 143 confirms that an IMAP connection is possible. A positive response is a standard greeting from EIMS.

To login you to an account enter a Number Login Username Password then hit enter.

Here is an example:

00001 login fred flintstone

The number doesn't matter, and in the example above the username would be fred and the password is flintstone.

To aviod the possiblity of locking the mailbox end by issuing the following command instruction:

00002 logout

SMTP

To test the basic capability of EIMS accepting SMTP connections, telneting to port 25 will yield the standard server greeting. One could then issue a series of commmands and actually send out a mail message but for most this will be too cumbersome. If the server will accept the connection it is best to use a mail client that will produce a session log if you need to confirm that EIMS is interacting correctly to construct and send messages.

Beyond a basic connection the EHLO command can be used for further evidence that the connection is stable and that the transmission of data is clear.

Similar to the example below, type the EHLO command followed by a domain name:

EHLO qualcomm.com

The EIMS server should respond with a list of the extended SMTP commands that it supports. To end the session issue the "quit" command and the connection will be terminated.

KEYWORDS: EIMS, TELNET, PROBLEMS, TROUBLESHOOT, ADMIN