How can i backup var/log files/folders ?
- Log files/folders changes (log updates) should be automatically updated from original log file/folder to duplicate file/folder.
If I understand, what you need,then simplest thing might be just to specify multiple saving locations in /etc/syslog.conf, example from syslog manpage.
As you can see, every kernel message is stored in /var/adm/kernel,and every critical kernel message will be sent to logserver on machine 'finlandia' and displayed on console as well. You will have to edit logrotate in /etc/logrotate.d/syslog, so logs will be rotated properly on your backup partition.
I believe this is better solution than backup with cron,because backup-logs are created everytime something is logged :-)
Anyway, if you will be interested in creating a backup log-server on remote machine, I recommend NSA RHEL Security Guide. Page 66. It helped us quite a lot when I was setting up a Rhel server with my classmates :-)
so you want to keep only one backup and not multiple backups for different points in time? than the easiest way to go should by using