$Id: README.monitors,v 1.3 1998/04/12 17:27:33 trockij Exp $

The following monitors are provided with the distribution, to get
you started. It's simple to add your own monitors. See the man page
for "mon" to learn how.

fping.monitor
-------------
    This pings a list of hosts efficiently using the fping program,
    from the Satan distribution. fping.monitor is just a simple
    shell wrapper for fping, and is normally invoked with just the
    list of hosts to ping. Here's a trick: say you don't want to
    trigger an alert until a machine has unpingable for some number
    of minutes. Give fping.monitor the arguments "-r 3 -t 240000".

ping.monitor
------------
    Similar to fping.monitor, but uses the system's ping program.
    This serializes the pings, which is normally bad to do. This
    is simply an alternative to fping.monitor, if you can't get
    fping to compile. I've only tested it with Linux and Solaris.

freespace.monitor
-----------------
    This will monitor disk space usage of a particular NFS server.
    Arguments are supplied as "path:kBfree [path:kBfree...]". If
    free space dips below kBfree, then it returns a failure condition,
    and the output is how much space is left on that server.

    If you use this monitor, use separate mounts for the volumes that
    you want to test, mounting them with the "-o ro,intr,soft" options,
    so things don't hang too bad if the server is down.

    You should use the ";;" directive to the monitor line, because
    freespace.monitor doesn't take a list of hosts. Here's an example:

watch nfsservers
        service fping
            interval 5m
            monitor fping.monitor
            alert mail.alert mis-alert@company.com
            alert netpage.alert mis-pager
            alertevery 60m
        service freespace
            interval 10m
            monitor freespace.monitor /server1:5000000 /server2:5000000 ;;
            alert mail.alert mis-alert@company.com
            alert netpage.alert mis-pager
            alertevery 60m


tcp.monitor
-----------
    Useful to see if it's possible to connect to a particular port
    on a particular server. This is over-simplified, and does not yet
    support parsing of the output from these services. Options are
    "-p port" to tell which port to check, and a list of hosts.
    This uses Wietse Venema's tcp_scan software from the Satan package.


http_t.monitor
--------------
    This monitor, contributed by Jon Meek (meekj@pt.cyanamid.com), will
    use HTTP to connect to a server, get a page, and log the transfer
    speed of the transaction. It uses the Time::HiRes Perl module,
    available from CPAN. It can also register a failure if the transfer
    doesn't complete within a certain number of seconds. See the
    source code for an explanation of the arguments.
