More and more companies are depending on Linux to run their mission critical networks and store their most important data. This expert guide shows Linux system administrators exactly how to protect those resources and networks, using the powerful open source tools the Linux community has developed. Start by learning how to prepare your Linux system for a production environment, including identifying system vulnerabilities, planning for day-to-day security administration; implementing firewalls, and more. Review the key steps involved in securing filesystems, email, web servers, and other key applications; then learn how to protect applications running in a mixed Linux/Unix and Windows NT environment. Linux System Security book contains invaluable "rules of thumb" that can help any Linux sysadmin leverage the security expertise that usually earned only through hard-won experience. It's informal and witty -- but when it comes to protecting your systems and resources, this book is deadly serious! For all Linux sysadmins familiar with the basics of system administration and TCP/IP network administration.