Sentry Firewall CD-ROM is a Linux-based bootable CDROM suitable for use as an inexpensive and easy to maintain firewall, server, or IDS(Intrusion Detection System) Node. The system is designed to be immediately configurable for a variety of different operating environments via a configuration file located on a floppy disk, a local hard drive, and/or a network via HTTP(S), FTP, SFTP, or SCP. The Sentry Firewall CD is a complete Linux system that runs off of an initial ramdisk, much like a floppy-based system, and a CD. The default kernel is a current 2.4.x series kernel with various Netfilter patches applied. An
OpenWall-patched current 2.2.x kernel is also available on the CD.