Where the backups are stored in Plesk? (path)

The backups in Plesk are stored in directory var/log/psa/dumps

Path for Iptables (Apache)

/etc/init.d/iptables is the INIT script which is used to start, stop the service and/or to save the rulesets.

/etc/sysconfig/iptables this is the file that holds the saved rulesets.

/sbin/iptables and this is the iptables binary.

Log files in an apache server with Plesk

Plesk Error Log

Path: /var/log/messages

Apache Error Log

Path: /var/log/httpd/error_log

Domain's Error Log
Path: var/path_to_domain/statistics/error_log