$Id: README.hints,v 1.1.1.1 2004/06/09 05:18:06 trockij Exp $ 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.