ISC-dhcpd with newsyslog

Problem
Problem: my DHCP server crashed every few days.

Analysis
A quick look at the log file gave a hint that the crash occured just when newsyslog was rotating the log files:

Feb 15 02:59:46 wolfje dhcpd: DHCPACK on 172.25.129.98 to 00:26:4a:e8:ab:b9 via em3 Feb 15 03:00:00 wolfje newsyslog[92690]: logfile turned over due to size>100K Feb 15 09:02:45 wolfje dhcpd: Internet Systems Consortium DHCP Server 4.2.3-P2 ... further boot log of ISC-dhcpd ...

Feb 20 13:59:39 dhcpd: DHCPREQUEST for 172.25.129.67 from 00:13:d3:a2:57:59 via em3 Feb 20 13:59:39 dhcpd: DHCPACK on 172.25.129.67 to 00:13:d3:a2:57:59 via em3 Feb 20 14:00:00 newsyslog[14620]: logfile turned over due to size>100K Feb 20 15:30:24 dhcpd: Internet Systems Consortium DHCP Server 4.2.3-P2 Feb 20 15:30:24 dhcpd: Copyright 2004-2012 Internet Systems Consortium. Feb 20 15:30:24 dhcpd: All rights reserved. ... further boot log of ISC-dhcpd ...

Now I recently added the following line to : /var/log/dhcpd.log	dhcpd:audit	640 10	   100	*     C	/var/run/dhcpd/dhcpd.pid

The PID file means that newsyslog will send a SIGHUP to the process ID (PID) of dhcpd when it is rotated.

From the DHCP FAQ:


 * How do you have dhcpd reload its configuration file?
 * At this time, the dhcpd server doesn't have any reload mechanism. It doesn't handle HUP signal nor have a 'soft' reconfiguration method. The server has to be stopped and restarted.

So this SIGHUP caused the DHCP server to stop.

Solution
My  configuration was at fault. It was easily solved by using syslog, and sending a SIGHUP to syslog instead of dhcpd:

From : log-facility local7;
 * 1) Log to syslog

And in : /var/log/dhcpd.log	dhcpd:audit	640 10	   10	*     C