In my experience as a Systems Administrator, it has come up quite often to create a script to rotate and compress rather large log files.
The daily mode is intended to be run daily (obviously) , gzipping the previous days log file. The monthly mode, run monthly (obviously), then tar’s up all the previous month’s gzip files into one big tarball.
Note that this script assumes the log filenames are assorted by the filename + date (year/month/day). This can obviously be modified to suit the specific syntax of your log file names.
Here is the script :
#!/bin/sh # Rotate / compress old logs # Star Dot Hosting yesterday=`date --date='1 day ago' +%Y-%m-%d` lastmonth=`date --date='1 month ago' +%Y-%m` lasttwomonth=`date --date='2 months ago' +%Y-%m` currentmonth=`date "+%Y-%m-%d"` logdir="/path/to/log/directory" logfilename="log-file-name" #gzip yesterdays log if [ "$1" = "daily" ] then gzip $logdir/$logfilename.$yesterday.log exit 0 #tar all last month's logs on the 1st of each month elif [ "$1" = "monthly" ] then tar -C $logdir -cf $logdir/$logfilename.$lastmonth.tar $logdir/$logfilename.$lastmonth-*.log.gz && rm -f $logdir/$logfilename.$lastmonth-*.log.gz exit 0 else echo "no or invalid arguments given." echo "syntax : ./logcompress.sh daily or ./logcompress.sh monthly" exit 1 fi
I simply make two crontab entries :
0 3 * * * /bin/sh /usr/local/bin/logcompress.sh daily 0 5 1 * * /bin/sh /usr/local/bin/logcompress.sh monthly
The above entries run the script daily at 3:00am, and monthly on the 1st of every month at 5:00am, this ensures the script isn’t run at the same time on the 1st as the daily job.