The init command is a cool tool to do simple process monitoring. Add :respawn: entry to your /etc/inittab, if you need procees to be respawned. See the online manual page by typing 'man init' at bash prompt.
On linux systems you can find the following packages. If it is not in the main cdrom than you must check in the contrib cdrom :
$ top $ ktop $ gtop
Visit the web site of daemontools at http://www.pobox.com/~djb/daemontools.html
To install the daemontools RPM, do -
# rpm -i /mnt/cdrom/daemontools*.html # man supervise
supervise monitors a service. It starts the service and restarts the service if it dies. The companion svc program stops, pauses, or restarts the service on sysadmin request. The svstat program prints a one-line status report. See man page by 'man supervise'
svc - control a supervised service.
svc changes the status of a supervise-monitored service. dir is the same directory used for supervise. You can list several dirs. svc will change the status of each service in turn.
svstat - print the status of a supervised service.
svstat prints the status of a supervise-monitored service. dir is the same directory used for supervise. You can list several dirs. svstat will print the status of each service in turn.
cyclog writes a log to disk. It automatically synchronizes the log every 100KB (by default) to guarantee data integrity after a crash. It automatically rotates the log to keep it below 1MB (by default). If the disk fills up, cyclog pauses and then tries again, without losing any data. See man page by 'man cyclog'
accustamp puts a precise timestamp on each line of input. The timestamp is a numeric TAI timestamp with microsecond precision. The companion tailocal program converts TAI timestamps to local time. See 'man accustamp'
usually watches a log for lines that do not match specified patterns, copying those lines to stderr. The companion errorsto program redirects stderr to a file. See 'man usually'
setuser runs a program under a user's uid and gid. Unlike su, setuser does not gain privileges; it does not check passwords, and it cannot be run except by root. See 'man setuser'
There are commercial monitoring tools available. Check out -