Fetch program specific log from syslog to own log file

pgpool2_log_process.txt

### Create rsyslog entry to catch log data [based on 'pgpool' name] in '/etc/rsyslog.d/pgpool2.conf'
  if ( $programname == "pgpool" ) then {
    action(type="omfile" fileOwner="postgres" fileGroup="postgres" fileCreateMode="0644" file="/var/log/pgpool2/pgpool2.log") stop
  }

### Create logrotate configuration in '/etc/logrotate.d/pgpool2.conf'
  /var/log/pgpool2/pgpool2.log {
      daily
      rotate 30
      compress
      delaycompress
      notifempty
      missingok
      dateext
      dateformat -%d%m%Y
      copytruncate
      create 0644 postgres postgres
  }

  REF: 
    https://en.linuxportal.info/tutorials/web-hosting/other/rotate-and-output-log-files-using-the-logrotate-program
    https://www.tecmint.com/install-logrotate-to-manage-log-rotation-in-linux/
    https://linuxconfig.org/logrotate
    https://unix.stackexchange.com/questions/33447/why-we-should-use-create-and-copytruncate-together

### re-init rsyslog
  # pkill -HUP rsyslog

### restart pgpool & rsyslog
  # service rsyslog restart
  # service pgpool2 restart

### cleanup log file [OPTIONAL]
  # truncate -s 0 {log_file}		EX: truncate -s 0 /var/log/syslog