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PortServer FAQ

FAQ: PortServer Family

How do I set my port to bypass the PortServer and give me a login from one specific host?

set port auto=on dport=23 dest= range=1
This will directly connect port 1 via telnet (dport=513 for rlogin) to You will not receive a login from the PortServer. You will not be able to run multiple sessions.

Depending on who I login as, how do I bypass the PortServer command line and connect to a host?

set logins login=on range=1-16
set user name=host_a auto=on dport=23 dest=
set user name=host_b auto=on dport=513 dest=
You will be prompted with a login from the PortServer. Logging in as host_a will directly connect via telnet to Logging in as host_b will directly connect via rlogin to You will not be able to run multiple sessions. Using the menu option may also be an alternative to easily connect to multiple hosts. The menu option is available with the PortServer II only, refer to the PortServer II User''''s Guide for configuration. Using menu will allow multiple sessions.

How do I connect over the network, directly into a port(s)?

Commonly refered to as "reverse telnet". There are two ways to directly connect to a port(s), thru the socket id "20xx" and "21xx", or thru altip. "xx" equals the actual port number.
  set port dev=prn range=5

The port must be set to a device type that supports "reverse telnet". Acceptable device types are prn, rp, mout, mio, host (if DCD is high). Refer to the manual for specifics on device types. Set auth defaults to unrestricted so it is probably not needed but do check this if you cannot connect. Specifics to set auth is in the manual.

With the port set to one of these device types will allow you to:

   telnet termserv1 2005
This will connect you directly to port 5 of termserv1. The PortServer will NOT allow you to telnet to the PortServer AND then telnet to 2005, the PortServer II does support this.

For altip:
set port dev=prn group=77 range=1-5
set altip ip= group=77
You can then do:
With this example telneting to will connect to the first open port of ports 1-5. Use a group id greater than 65 for the PortServer II or greater than 17 for the PortServer. You can also use the group option within altip to be a specific port. You have up to 16 alternate ip addresses to use (other than the PortServer''''s own ip).

How do I setup a permanent connection from a port on one PortServer to a port on another PortServer?

For this example I have a PC (no tcp/ip) where I''''m connecting my com port to port 5 of the PortServer-ip= I want this port to permanately connect to port 10 of a different PortServer-ip= that I have a printer connected to.
On PortServer-
set port dev=term auto=on dport=2010 dest= range=5
On PortServer-
set port dev=prn range=10
In the above example, dport=2110 would be used if you were sending strictly binary data (raw).

How do I get rid of the Digi banner that appears at the beginning of my print jobs?

set logins mess=1 range=0
set logins mess=2 range=0
This command is not documented in the manuals. It clears out the two message databases which default with ''''Digi International PortServer 16''''. This is only valid for the PortServer not the PortServer II.

How do I reset the PortServer/PortServer II products back to factory defaults?

Hold both the left and right arrows on the front panel down.  Turn the power on the PortServer/PortServer II module OFF and then ON. Watch for ''''EP'''' on the PortServer or ''''CL'''' on the PortServer II to appear on the front panel display, then release the left and right arrow buttons.

How do I setup RARP?

The PortServer can be assigned its ip address by one of two ways (the default is, logging in from one of the ports (follow the ''''Quick Start'''' section in the manual), or if no ip address is set it will send out a RARP request. To set up RA RP on most Unix systems, this example is for SCO, do the following:
  1. stop tcp
  2. Edit /etc/ethers add in the PortServer''''s ethernet address (this is on a sticker at the bottom of the PortServer) along with a name, examples are in the /etc/ethers file.
  3. Edit /etc/hosts add in the PortServer''''s ip address and the name you specified in /etc/ethers.
  4. Edit /etc/tcp uncomment out the 4-5 ''''if'''' and ''''fi'''' lines in regards to RARP.
  5. start tcp
  6. Boot the PortServer

What does the rtty program do?

The ''''rtty'''' program is available ''''as is'''' meaning source is provided but Digi is not responsible for maintanence, support, etc. There are compiled versions for a handful of Unix OS''''s, or you can grab the source and compile it yourself. The ''''rtty'''' program works with BSD style pseudo devices (not streams). ''''rtty'''' is a daemonized program run from Unix, it essentially allows you to assign a specific BSD pseudo device to a specific port on the PortServer. Check to see that these pseudo devices exist in /dev.

Use the highest pseudo device available (lower ones may be used for things like ''''telnet''''), for example ''''ttyp0-ttyp31'''' you want to start with ''''ttyp31. You should be able to create more pseudos if needed, refer to the OS on how to add. This is commonly used for printers or dial-out modems where the ''''realport'''' driver is not being used. Exact syntax for ''''rtty'''' is in the Appendix of the PortServer manual.

What sort of monitoring/diagnostic tools do we have available?

The PS/PSII both have Post-diagnostic testing for hardware verification, you can monitor ports and ethernet activity from the front panel. Both can be SNMP managed, network statistics gathered. The PSII has the set trace utility for debugging things such as PPP, serial, ICMP, etc. The PSII also supports RADIUS.

NOTE for users of Front Panel Diagnostics
Some terminals require DCD to be high or floating in order to initiate communication. Use of a fully pinned out cable which wires anything from the PortServer (or PSII) to DCD will initially tie this signal low and may prevent the terminal from communicating. In this case, use of a 3 wire cable which only connects Tx, Rx, and SG is recommended.

How can I change the password for a user on a PortServer or PortServer II? 

The PS/PSII both use the command newpass for this feature login as the user and issue the command newpass or as root newpass na=[username]. Please note that on a PortServer, the password must start with a letter.

I forgot the root password after changing it.
          If you do not remember the root password after having changed it, and you not have a backup configuration file as a result of the cpconf command, you will need to reset the PortServer to factory defaults.

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