Using logadm, a powerful log rotation tool
One of the secret and powerful tools that are mostly forgotten is
logadm. The tool allows system and application logfiles to be rotated at a configureable interval.
The configuration file
/etc/logadm.conf contains the information which logfile need to be rotated and how.
logadm control the configuration file with some of the following options, check the manpage for more details:
General options: -w entryname write entry to config file Options which control how a logfile is rotated: -a cmd execute cmd after taking actions -b cmd execute cmd before taking actions -o owner new empty log file owner -g group new empty log file group -m mode new empty log file mode -c copying it and truncating the original Options which control the expiration of old logfiles: -C count expire old logs until count remain
logadm run on most solaris based systems each day at 3:10 am. With the
-p option you could specify a period of time if required. I recommend to use as “entry name” the logfile including the path, this should be unique enough.
If you would like to rotate the exim main logfile every day without restarting the service I also recommend the option
-c. This will copy the log entries from the old logfile and truncate it after.
.- keep 10 files .- copy and truncating $ logadm -w /var/log/exim/main -p 1d -C 10 -o mail -g mail -m 640 -c -N `- write to config `- one a day `- owner and group `- prevent error if file not exists
Because of the
-w write entry to config file option, this line will appear in
Maybe you’ve script that should send the exim panic log and rotate the logfile by his own? Yes this is also possible with logadm but you don’t require the
$ logadm -p now -C 10 -o mail -g mail -m 640 /var/log/exim/panic `- run the rotation of the logfile now
By rotating a logfile with
logadm it adds
.<number> at the end of the old files. This number increase by the date.
Please check the manpage for more options,
logadm supports different log rotation types (count or size) and could also
gzip your old files.