3. Security, Optimization and Upgrade


Now that we have installed a base system, the next three chapters will concentrate on

  • How to tighten the security of our configured system.

  • Optimise our sytem to perform at its peak.

  • Upgrade our machine for the latest kernel.

Please note when we talk of tightening the security we are referring to the features available within the base installed system and not to any new additional software. We will talk about that later in this book.

Table of Contents
5. General System Security
5.1. BIOS
5.2. Security as a Policy
5.3. Choose a right Password
5.4. The root account
5.5. The /etc/exports file
5.6. Disable console program access
5.7. Disable all console access
5.8. The inetd - /etc/inetd.conf file
5.10. The /etc/host.conf file
5.11. The /etc/services file
5.12. The /etc/securetty file
5.13. Special accounts
5.14. Blocking; su to root, by one and sundry
5.15. Put limits on resource
5.16. Control mounting a file system
5.17. Conceal binary RPM
5.18. Shell logging
5.19. The LILO and lilo.conf file
5.20. Disable Ctrl-Alt-Delete keyboard shutdown command
5.21. Physical hard copies of all-important logs
5.22. Tighten scripts under /etc/rc.d/
5.23. Bits from root-owned programs
5.24. The kernel tunable parameters
5.25. Refuse responding to broadcasts request
5.26. Routing Protocols
5.27. Enable TCP SYN Cookie Protection
5.28. Disable ICMP Redirect Acceptance
5.29. Enable always-defragging Protection
5.30. Enable bad error message Protection
5.31. Enable IP spoofing protection
5.32. Log Spoofed, Source Routed and Redirect Packets
5.33. Unusual or hidden files
5.34. System is compromised !
6. Linux General Optimization
6.1. The /etc/profile file
6.2. Benchmark Results
6.3. Benchmark results-i586
6.4. Benchmark results -i486
6.5. The bdflush parameters
6.6. The buffermem parameters
6.7. The ip_local_port_range parameters
6.8. The /etc/nsswitch.conf file
6.9. The file-max parameter
6.10. The ulimit parameter
6.11. The atime and noatime attribute
6.12. Tuning IDE Hard Disk Performance
6.13. Better manage your TCP/IP resources
7. Configuring and Building a Secure, Optimized Kernel
7.1. Pre-Install
7.2. Uninstallation and Optimization
7.3. Securing the kernel
7.4. Compilation
7.5. Kernel configuration -Part "A"
7.6. Kernel configuration -Part "B"
7.7. Kernel configuration -Part "C"
7.8. Kernel configuration -Part "D"
7.9. Kernel configuration -Part "E"
7.10. Installing the new kernel
7.11. Delete programs, Edit files pertaining to modules
7.12. Create a emergency Rescue and Boot floppy disk