I've noticed that one system user is constantly downloading a single JPEG file (every few seconds) via FTP server. The source IP is actually assigned to the server itself. I've tried to use tools like lsof, ps, top. I've also checked the cron jobs with no luck. Could you please advise how I can trace the source of this process, script? Please note that this server is running cPanel.
I could use strace however the process is not running long enough to catch it.
# tail /var/log/xferlog
Wed Jan 23 14:21:26 2013 0 xxx.xxx.xxx.xxx 14558 /path_to_dir/file.jpg b _ o r user ftp 1 * c
Wed Jan 23 14:21:26 2013 0 xxx.xxx.xxx.xxx 14558 /path_to_dir/file.jpg b _ o r user ftp 1 * c
Wed Jan 23 14:21:27 2013 0 xxx.xxx.xxx.xxx 14558 /path_to_dir/file.jpg b _ o r user ftp 1 * c