This document is designed as an introduction on how the Sentry Firewall CDROM works and how to get started using the system. The Sentry Firewall CD is a Linux-based bootable CDROM suitable for use in a variety of different operating environments. The system is designed to be configured dynamically via a floppy disk or over a network.. . .
This document is designed as an introduction on how the Sentry Firewall CDROM works and how to get started using the system. The Sentry Firewall CD is a Linux-based bootable CDROM suitable for use in a variety of different operating environments. The system is designed to be configured dynamically via a floppy disk or over a network. This allows one to configure the system dynamically, eventhough much of the actual system is on read-only(CDROM) media.

There are several advantages of using a CDROM based system in various security related environments. The main system is centered around the ramdisk; a compressed file system image which is loaded into RAM at boot time. Any changes to the ramdisk image are temporary, and will be undone upon the next reboot. Furthermore, the ramdisk, kernel, binaries, etc, related to the operating system are kept on read-only media(CDROM). This means that if the security of a box running a CDROM based system is ever compromised the attacker can at best own the box until the next reboot. So there is no real threat of having to go through the tedious task of rebuilding and hardening the system after a successful attack is discovered.

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