Write Naemon Log

We can write to naemon.log file by issue command

OMD[monitor@501264b41d2d]:~/var/naemon$ pwd
/omd/sites/monitor/var/naemon
OMD[monitor@501264b41d2d]:~/var/naemon$ echo "[$(date +%s)] User Activity msg TEST log" >> naemon.log 

Linux command date +%s will print time in current time since Epoch 1970

In C program, we can implement this function with bash shell via system( bash cmd )

int writeLogFile( char *msg )
{
   char str_msg[1024];
   sprintf( str_msg, "echo \"[%d] User Activity %s \" >> /omd/sites/monitor/var/naemon/naemon.log",(int)time(NULL), msg);
   printf(str_msg);
   system(str_msg);
   return 0;
}

logrotate

we can config naemon.log to rotate as following

OMD[monitor@906094f86a76]:~/etc/logrotate.d$ more /omd/sites/monitor/etc/logrotate.d/naemon 
/omd/sites/monitor/var/naemon/naemon.log {
    daily
    rotate 7
    nocompress
    olddir /omd/sites/monitor/var/naemon/archive
    dateext
    dateformat -%Y%m%d
    missingok
    notifempty
    postrotate
      [ -f /omd/sites/monitor/tmp/lock/naemon.lock ] && kill -s USR1 `cat /omd/sites/monitor/tmp/lock/naemon.lock`
    endscript
    create 0664 monitor monitor
}

/omd/sites/monitor/var/naemon/livestatus.log {
        missingok
        rotate 0
        compress
        delaycompress
        notifempty
        create 640 monitor monitor
}

A file thruk.log was an activity user log. We can logrotate as following

OMD[monitor@906094f86a76]:~/etc/logrotate.d$ more /omd/sites/monitor/etc/logrotate.d/thruk  
/omd/sites/monitor/var/log/thruk.log {
        daily
        rotate 3
        nocompress
        olddir /omd/sites/monitor/var/log/archive
        dateext
        dateformat -%Y%m%d
        missingok
        notifempty
        create 660 monitor monitor
}

/omd/sites/monitor/var/thruk/cron.log {
        missingok
        rotate 0
        compress
        delaycompress
        notifempty
        create 660 monitor monitor
}