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System Configuration—Keeping it UpdatedCustomizing and Rebuilding KernelThe default FreeBSD GENERIC kernel is good enough for a typical installation.It contains support for the most commonly used hardware including networkinterfaces, USB ports, SCSI disk, and other commonly used hardware that are mostlikely to exist on any computer or server. However, there is no guarantee that allyour installed hardware is supported by this kernel. It is also not the ideal kernel forthe high performance servers. There is a lot of hardware support compiled into thiskernel that you probably won't ever need.Creating a custom kernel for your server has many advantages that include (but notlimited to) the following:• Removing support for unnecessary hardware from the kernel will lead tosmaller memory footprint and faster system boot up process.• Custom kernel would only support your currently installed hardware thatwas unavailable in the default GENERIC kernel.• Custom kernel may include support for some features that are not availablein GENERIC kernel, such as Firewall and NAT support.Removing unnecessary modules from the statically built kernel does notmean that you are completely removing the feature. Most modules can beloaded dynamically during system run time when needed.The kernel configuration files can be found under the /usr/src/sys/i386/confdirectory. This is the default directory for the i386 platform. However, if you are noton i386 platform, you should use the relevant subdirectory to your platform as listedin the following table:Subdirectory in /usr/src/sysamd64i386ia64pc98powerpcsparc64PlatformAMD's AMD64 and Intel 64 platformIntel 32bit PlatformIntel IA-64 (Itanium) PlatformNEC PC-98x1 PlatformPowerPC platformSun Microsystems' UltraSPARC PlatformThe configuration file is a text-based configuration file that contains informationabout the modules and options that are supposed to be statically compiled intothe kernel.[ 38 ]