No entry for system.log in /etc/newsyslog.conf In How can I extend the time when system.log gets turned over? and How to find recently connected external disks? it says that /etc/newsyslog.conf should have an entry for /var/log/system.log that I can edit to change how often this log file is rotated and how many old versions are kept. But on my system there's no entry for this file. The contents of my file are (omitting the big block of comments at the top):

# logfilename          [owner:group]    mode count size when  flags [/pid_file] [sig_num]
/var/log/ftp.log            640  5     1000 *     J
/var/log/hwmond.log         640  5     1000 *     J
/var/log/ipfw.log           640  5     1000 *     J
/var/log/lpr.log            640  5     1000 *     J
/var/log/ppp.log            640  5     1000 *     J
/var/log/wtmp               644  3     *    @01T05 B


I also looked in the files in /etc/newsyslog.d, none of them contain system.log, either.

So how does system.log get rotated now, and is there a setting I can change to control it?
An answer was posted in this ServerFault question.

Configuration of system.log moved in 10.9 to /etc/asl.conf. It should have a section like:

# Rules for /var/log/system.log
&gt; system.log mode=0640 format=bsd rotate=seq compress file_max=5M all_max=50M
? [= Sender kernel] file system.log
? [&lt;= Level notice] file system.log
? [= Facility auth] [&lt;= Level info] file system.log
? [= Facility authpriv] [&lt;= Level info] file system.log


The line beginning with &gt; system.log is analogous to the old newsyslog.conf line.

After editing the file, do:

sudo killall -HUP syslogd


to make it reload the configuration file.