Has anyone had any issues with logrotate before that causes a log file to get rotated and then go back to the same size it originally was? Here's my findings:

Logrotate Script:

/var/log/mylogfile.log {
    rotate 7
    daily
    compress
    olddir /log_archives
    missingok
    notifempty
    copytruncate
}

Verbose Output of Logrotate:

copying /var/log/mylogfile.log to /log_archives/mylogfile.log.1
truncating /var/log/mylogfile.log
compressing log with: /bin/gzip
removing old log /log_archives/mylogfile.log.8.gz

Log file after truncate happens

[root@server ~]# ls -lh /var/log/mylogfile.log
-rw-rw-r--  1 part1 part1 0 Jan 11 17:32 /var/log/mylogfile.log

Literally Seconds Later:

[root@server ~]# ls -lh /var/log/mylogfile.log
-rw-rw-r--  1 part1 part1 3.5G Jan 11 17:32 /var/log/mylogfile.log

RHEL Version:

[root@server ~]# cat /etc/redhat-release 
Red Hat Enterprise Linux ES release 4 (Nahant Update 4)

Logrotate Version:

[root@DAA21529WWW370 ~]# rpm -qa | grep logrotate
logrotate-3.7.1-10.RHEL4

Few Notes:

• Service can't be restarted on the fly, so that's why I'm using copytruncate
• Logs are rotating every night, according to the olddir directory having log files in it from each night.