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Re: (ASCEND) SNMP the hard way

        Dr. Wolfgang Beneicke asked:

>Last saturday though it caught me bad: I couldn't connect from my office
>to issue the "reset" command in debug mode. Ouch.

>Now, there is no SNMP around, not in the MAX's network (just about 200
>hosts...:-), and not in my 1-host-network. Question to the Knowing Ones:
>is there a way to cause the MAX to reboot using SNMP commands without a
>SNMP beast like HP OV? Say, an awk script?
>Or do I have to throw 80 connect requests plus Immed Modem feature at it

>Any ideas welcome, a fixed patch release _very_ welcome.

        If you Max is "locking up", what assurance do you have that
        the Max will respond to SNMP commands when "locked"?  In your 
        place, I would guess "none".

        A short-term, cheap, and easy way to do what you wish to
        do would be to plug the Max's power cord into a simple
        programmable timer.  They come in various wattages, and
        can be programmed to go "off" for a few seconds every
        two days at 4am (or whenever).

        This ugly and brute-force approach, while very low-tech
        and inelegant, has the advantage of being foolproof, 
        although blind to conditions when the reset would knock
        users offline for no good reason.

        There are also touch-tone phone controllable power switches
        that allow one to power-cycle any/all connected equipment.
        This would cover the need for a manual-intervention approach
        to the problem.  The products I have seen are "password 
        protected", so there is little chance of unauthorized use.

        One could also plug an external modem into the "console"
        port of the Max, and put in a single analog phone line
        to support last-ditch administration of the Max via direct
        dial-up connection.  (The line can also be handy in cases where
        a tech wants to call the NOC from the site.)

        I am demanding on the issue of reliable service, so at all pops, I
        provision an analog phone line, a modem, and an ASCII terminal
        controlled port switch that allows a technician to dial up an 
        "unreachable" pop, and connect his terminal to any of the gear,
        including the Maxen, the AC power relays, the battery bank 
        controller, and the backup generator.  Most everything comes 
        with a serial port for admin and config, so this is the ultimate 
        in last-ditch options if you are willing to have someone spend 
        an afternoon figuring out the differences between all the "RS-232
        Standard" interfaces on all the gear.

        As for a "deadman timer", I would guess that the best
        mechanism would be a script that parses the radius log file
        and the syslog, and decides when a Max has gone catatonic.
        It would then communicate with the Max via SNMP, or if SNMP
        requests go unanswered, communicate via an old-style modem
        chat script over a serial port to a power-cycle box that 
        could be commanded via an ASCII terminal.  There are more
        than a few freeware SNMP packages out there, with the most
        often-mentioned being "scotty", and the CMU-snmp packages.
        There are Perl interfaces for both packages, I hear.
        
        As for awk, you and I may be the last two people on Earth
        to think first of awk rather than Perl.  Even I would suggest 
        that you use Perl in this case, since the SNMP package 
        interfaces exist now, and are fairly well documented.

 Surfing the electromagnetic spectrum, looking for that perfect Hertzian wave

james fischer                                jfischer@supercollider.com

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