watch_dhcp.pl: monitor a remote DHCP server and launch a local server
when needed.

Usage: watch_dhcp.pl [--server=server] [--client=client] [--ether=ether]
	[--timeout=timeout] [--sleep=sleep] [--wait=wait]
	[--start=start] [--stop=stop]
	[--scopy=scopy_from] [--copy-files=conf,file,list]
	[--ident=ident]
 server:  DHCP server name or IP.
 client:  Local IP address.
 ether:   Local ethernet address.
 timeout: Timeout for network operations.
 sleep:   Interval between monitoring.
 try:     Number of successive (bad/ok) tries before taking action (start/stop).
 start:   Command to start the local DHCP daemon.
 stop:    Command to stop  the local DHCP daemon.
 copy:    If set, indicates a user@host to secure-copy DHCP server files from (defaults to false, i.e. do not copy and needs ssh(1) and scp(1)).
 files:   List of files that need to be copied (defaults: /etc/dhcpd.conf,/var/state/dhcp/dhcpd.leases).
 ident:   SSH Identity to use with scp (default: ${HOME}/.ssh/dhcp-identity.

All options have reasonable values on a UNIX/Linux machine.

 Notes:

   .- This script will fail if remote DHCP server contains
unresolvable server names in its configuration.

.- It uses secure shell (ssh and scp) to update configuration files.

.- The machine that is running the test MUST BE a KNOWN client of the
remote DHCP server.

.- The files Makefile.linux, watch_dhcp.init.d, watch_dhcp.logrotate
can be used to install this exemple as a service. Just issue the
following command (as root):

	make -f Makefile.linux

The makefile is suited for RedHat Linux box. Inspect the Makefile and
change commands and directories as needed four your machine.