Getting Data In

Rsyslog Log Rotation

dillardo_2
Path Finder

We need to rotate syslog files once they reach a certain size.
Our directory structure looks like the following:

/opt/splunk/syslog/datasource1
/opt/splunk/syslog/datasource2
/opt/splunk/syslog/datasource3

etc.

Once files in the source folders reach 1GB for example, we need them to be moved to /opt/splunk/old_files

Has anyone successfully set up a rotation script?

0 Karma

Jawahir
Communicator

dillardo_2
Path Finder

Thanks, I did see this and have tried using logrotate. When we rotate the logs, they need to be moved to an archive folder outside of the syslog directory. When I add a command to move the files after postrotate, they files are moved successfully, but rsyslog stops working and must be restarted.

For example: 

/opt/splunk/syslog/*/*
 {
    daily
    missingok
    compress    
    notifempty    
    sharedscripts
    postrotate
                mv /opt/splunk/syslog/*/*.gz /opt/splunk/archive/;
    endscript
}
0 Karma

dillardo_2
Path Finder

This works for us, but rsyslog stops processing data and has to be restarted.

0 Karma

mydog8it
Builder

We create a new file per device type every hour and throw away files in 72 hours.

0 Karma

dillardo_2
Path Finder

@mydog8it, are you able to share your process and the script you are using? That would be helpful.

0 Karma

maraman_splunk
Splunk Employee
Splunk Employee

the hourly rotation is by design is you name the log file in rsyslog with mylog-yearmonthday-hour.log
(and that avoid any race condition as it is done directly by rsyslog)
to purge, just add a simple script in /etc/cron.d/purgemylog.cron
with hourly + run as a user who can delete log then run
find /var/log/mylogdir -type f -name \"mylog*.log\"-mtime +2 -delete
if you want to keep them 2 days
(or -mmin +xxx for more granularity)

make sure you specify the directory and a filename form in your find command to avoid any bad surprise...

0 Karma
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