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$Id: README.hints 1.1 Sat, 26 Aug 2000 15:22:34 -0400 trockij $

To be sure that mon works reliably, you may want to pay attention to the
following hints:

-Keep all alert and mon directories on a local filesystem. When
 the daemon is run, be sure that PATH does not contain remote
 filesystems.

-Do your best to make the mon host maintain independence of all systems
 that it is monitoring. Configurations may vary as different services
 are being monitored. For example, if you need to monitor whether
 DNS is operational, don't depend on DNS being available in the monitor
 script. Use a local hosts table which contains all the hosts referred
 to in the configuration file.

-If you're monitoring a network resource, don't depend on using the network
 to deliver alerts. If you subscribe to a paging service,
 get "Quick Page" or "tpage", and hook a modem and phone line up to
 the host which runs the daemon.

-Be aware of dependencies on services so that you're not surprised
 when one component fails, and then see that three more things fail
 because of this. If you get burnt by this situation, learn from it and
 see what you can do minimize the dependencies.

-Remember the power of "m4" if you want to do more complex things with
 the configuration file.

To be sure that mon works efficiently, respect these rules:

-Monitor programs should parallelize, like fping does. Instead of
 doing a bunch of fork(2)s to send out a lot of pings, it does
 it all from a single process, using nonblocking I/O, like Dan Farmer's
 "fping" from the Satan package.

-If you use hostnames in your hostgroups, consider keeping a local
 /etc/hosts file on the mon server. Monitors can generate lots of DNS
 traffic.