The ESI Dispatchers and Galil Controllers  

 

The ESI Dispatchers

The ESI software on the UNIX side talks to the two Galil controllers with "dispatchers." Galil controller 0 uses dispatcher 0 and Galil 1 uses dispatcher 1. The dispatchers are represented in the "Esicon" control panel by two buttons. If the button is not blue, then the dispatcher is not running. You can also check from the esieng account on koki by typing "esi status dispatcher2.0" and "esi status dispatcher2.1". Finally, you can type (on koki) "ps -auxww | grep dispatcher" which should show you the dispatcher processes. Note that they are of the form:

1642 ? S 0:00 dispatcher2 -s esi -n 1 -l /kroot/var/log/dispatcher_lo
1670 ? S 0:00 dispatcher2 -s esi -n 0 -l /kroot/var/log/dispatcher_lo

In this output note that the "2" in "dispatcher2" has nothing whatsoever to do with which dispatcher is run by that process. The "-n 0" and "-n 1" parts of the command give this information.

Normally, the dispatchers are started automatically when koki is booted. If the dispatchers are stopped, they need to be manually restarted from the esieng account on koki, using the commands: "esi start dispatcher2.0" and "esi start dispatcher2.1". These are also available from the esieng account's "Engineering" pull-down menu as "Restart dispatcher 0" and "Restart dispatcher 1".

The Galil controllers can also be accessed through the Lantronics terminal server and the main Galil serial ports. Galil 0 connects to server port 2001 and Galil 1 to port 2003. For example

telnet 192.168.5.2 2001

will attempt to connect to port 2001 and Galil 0. However, note that while the dispatchers are running, they "own" their respective ports on the terminal server, and attempts to telnet to the port will be refused. For example, if dispatcher 0 is running, any attempt to telnet to port 2001 will be refused by the Lantronix. Should you need to obtain a telnet connection to a Galil controller's serial port, you need to stop the corresponding dispatcher first.

Known Problems

The Lantronix needs to have a valid, properly terminated, ThinNet ethernet connection before you apply power to it in order to boot correctly. Unforuntately, just because it boots correctly doesn't guarantee that it will come up in a useful state.

The fundamental problem here is that neither the Lantronixs nor the Galils behave deterministically when power cycled. It appears that their serial interface hardware can spit out some stray characters when power is first applied. If the Lantronix senses these characters, it wrongly concludes that the Galil controller is trying to log into the Lantronix, and thus it puts that port into "Job Service". Once that happens, you can't telnet into the port nor can the dispatcher establish a connection to that port. The only recourse is to log into the main port (i.e., portless) connection, set privileged mode, and logout the spurious "connections" on ports 2001 and 2003, as described below. We would love to find a way to get the Lantronix to ignore these stray characters on power up, or to prevent the Galil from generating them on power up. So far we haven't. The problem can be corrected as follows:

  1. From the esieng account on koki, first stop any ESI dispatchers using the commands: esi stop dispatcher2.0 esi stop dispatcher2.1

  2. Telnet directly into the IP address of the Lantronix, but without specifying any port number:

    telnet 192.168.5.2

  3. It should respond with:

    Trying 192.168.5.2...
    Connected to 192.168.5.2.
    Escape character is '^]'.


    Lantronix ETS8P Version V3.5/1(970325)

    Type HELP at the 'Local_10> ' prompt for assistance

    Username>

  4. In response to the username prompt, type "esi", then hit the RETURN key. It should respond with: Local_10>
  5. To display the status of port 2001 (i.e., the one that connects to the main serial port of Galil controller 0), in response to the "Local_10>" prompt, type:

    show port 1.

  6. It should respond with something like:

    Local_10> show port 1
    Port 1 : Username:         Physical Port 1 (Job Service)
    Char Size/Stop Bits: 8/1   Input Speed: 19200
    Flow Ctrl: Cts/Rts         Output Speed: 19200
    Parity: None               Modem Control: None

    Access: Remote             Local Switch: None
    Backward: None             Port Name: Port_1
    Break Ctrl: Local          Session Limit: 4
    Forward: None              Terminal Type: Soft()

    Preferred Services: (Lat)
                     (Telnet)

    Authorized Groups : 0
    (Current)  Groups : 0

    Characteristics: Autoprompt Broadcast Loss Notify Verify
                     Remote Conf Telnet Pad

  7. If you have indeed stopped dispatcher 0 and no one else has already telnetted into this port, then the port should display as (Idle), i.e., the top line of the display should look like this:

    Port 1 : Username:          Physical Port 1 (Idle)

    If, with dispatcher 0 stopped and no one telnetted into port 2001, the port is shown as being in (Job Service), then the Lantronix is confused and needs to be set straight. Our initial output from the "show port 1" command illustrates this state. To correct the Lantronix's confusion, issue the following commands in response to the "Local_10>" prompt:

    set priv

    followed by hitting the RETURN key, to which it will respond with:

    Password>

    In response to the "Password>" prompt, type the password. If you don't know the password, ask one of the software on-call people.

  8. If you have done this correctly, the Lantronix should respond with a slightly different prompt: Local_10>> The second ">" character confirms that you have put the Lantronix into privileged mode.

  9. Now type the command: logout port 1 which should put port 2001 back into the "Idle" state. You can confirm this by issuing another "show port 1" command.

  10. To reset port 2003 (i.e., the one that connects to the main serial port on Galil controller 1), you would do the same sequence of operations, except substituting a "1" for a "3", e.g.:

    show port 3
    logout port 3
    show port 3

  11. Once you have used the commands "show port 1" and "show port 3" to confirm that both ports are in the "Idle" state, you should be able to establish telnet connections to the respective port numbers 2001 and 2003.

  12. To check that Galil controller 0 is responding appropriately:

    telnet 192.168.5.2 2001

    Once connected, hit the return key several times. If the Galil is responding, it should echo back a colon character (i.e., ":" ) as a prompt. If, instead, it echoes back a question mark, hit several more return keys until you get a ":" prompt. If you are unable to obtain a colon prompt, then that Galil controller probably needs to be reset or power cycled. Once you have confirmed that Galil controller 0 is responding and it has issued a ":" prompt, carefully (and without hitting any other characters) enter the telnet escape sequence (i.e., while holding down the control key hit the right-bracket key) to terminate the telnet connection to Lantronix port 2001.

  13. To check that Galil controller 1 is responding appropriately:

    telnet 192.168.5.2 2003

    and do the same as you did for the other controller. Once you have confirmed that Galil controller 1 is responding and it has issued a ":" prompt, carefully (and without hitting any other characters) enter the telnet escape sequence (i.e., while holding down the control key hit the right-bracket key) to terminate the telnet connection to Lantronix port 2003.

  14. At this point, you have confirmed that both the Lantronix and Galil controllers are properly initialized, so you should be able to restart both dispatchers from the Engineering pull-down menu in the esieng account on koki.

To determine which keywords are handled by which dispatcher, use one of the commands:

show -s esi memes | grep -i esi_dispatch_0
show -s esi memes | grep -i esi_dispatch_1

Trouble-Shooting the Dispatchers

If you tail the most recent dispatcher log file for a given dispatcher, it should give you some idea as to what the problem might be. The "esi status dispatcher2.0" or "esi status dispatcher2.1" given on koki should give you the path to this log file. To determine whether or not the Lantronix has booted correctly:

  1. Trying pinging it, i.e.:

    ping -sv 192.168.5.2
  2. Try logging into its master port (i.e., don't specify a port):

    telnet 192.168.5.2

If you can do both of these steps, then the Lantronix has successfully booted. However, as noted earlier, if the instrument (or pieces of it) have been power cycled, the Lantronix may have erroneously put either port 2001 or 2003 into "Job Service". In that case, follow the 14-step procedure outlined above to clear the problem.

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ESI Master
3 January 2000