If your /var/log/messages is infrequently updated, it may appear that your "dispatcher" script does not produce output.

Try adding "tail => 5" to the File::Tail constructor - this will make it behave more like the linux "tail" command, and immediately produce 5 lines of output (default is 0).

Try moving the Ping constructor outside the loop.

Why not combine the scripts, since they seem inter-dependent.

On my system, the DHCPACK line looks like this :

May  5 11:19:59 MyHostName dhcpd: DHCPACK on 192.168.0.94 to 00:50:56:
+ab:42:51 (localhost) via eth1
[download]

so, your regex-scanner is very dependent on the syntax produced. Double check that it matches the lines generated by your DHCP server.