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20030804: ldm back data

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  • Subject: 20030804: ldm back data
  • Date: Mon, 04 Aug 2003 12:07:31 -0600
>From: address@hidden
>Organization: ULM
>Keywords: 200308041746.h74HkZLd017877 LDM request

Adam,

>Is there a way to change the ldm so that i can get more then 1 hour worth of
>data back if a mcahine is down for a while??

Yes, but the age of the oldest product you can request ultimately
depends on the age of the oldest product in your upstream LDM host's
queue.  So, if your upstream host(s) is(are) only keeping an hour of
data, then that is all that you will be able to request.

How far back in time a data request goes is governed by the '-o' flag
on the lead rpc.ldmd process.  The LDM startup script, ldmadmin, does
not expose setting this parameter to the user.  If you wanted to change
the default value, you would need to edit ~ldm/bin/ldmadmin and add
setting of the '-o' flag.  This should be done in the main portion
of the script:

 ...

# build the command line

    $cmd_line = "rpc.ldmd";

    if ($debug) {
    $cmd_line .= " -x";
    }
    if ($verbose) {
    $cmd_line .= " -v";
    }

    $cmd_line .= " -q $pq_path $ldmd_conf > $pid_file";

    print "Starting the LDM server...\n";

    system("$cmd_line");

 ...

For instance, setting the value of the oldest product to request to
10000 seconds, would like something like:

$cmd_line .= " -q $pq_path $ldmd_conf -o 10000 > $pid_file";

You must set the '-o' value to a something less than 'max_latency'
which is the value of the '-m' flag.

So, '$cmd_line" should probably be set as follows for the example above:

$cmd_line .= " -q $pq_path $ldmd_conf -m 10000 -o 10000 > $pid_file";

Please review the rpc.ldmd man page carefully before modifying the LDM
startup, AND make a backup copy of ldmadmin so you can recover after
typos, etc.

Good luck!

Tom