# uname -a

# ls -l /boot/kernel/kernel

# ls -l /boot/kernel/*ko

# sysctl net.inet.ip.ttl=2

# cat /etc/sysctl.conf

# cat /boot/loader.conf

...
hint.acpi.0.disabled="1"

• Подключение звуковой карты (в старых версиях)

# kldstat

# kldload ipfw

# sysctl net.inet.ip.fw.enable=0

# cat /boot/loader.conf

...
if_em_load="YES"
snd_ich_load="YES"

• Сборка и установка собственного ядра
• Configuring the FreeBSD Kernel

• изменение функциональности ядра
• наложение заплаток безопасности на ядро
• уменьшение размера ядра
• повышение производительности

[server:~] # cp -r /boot/kernel/ /boot/kernel.generic/

• Анализ оборудования в FreeBSD

[server:~] # mount -t cd9660 /dev/cd0 /mnt/

[server:~] # cd /

[server:/] # tar -xvf /mnt/usr/freebsd-dist/src.txz

[server:~] # umount /mnt/

[server:~] # freebsd-update fetch

[server:~] # freebsd-update install

Задачи:

• уменьшенить размер ядра
• отключить IPv6
• добавить в ядро поддержку pf и altq
• вынести драйвера сетевой и звуковой карты в модули
• остальные модули не компилировать

[server:~] # less /usr/src/sys/conf/NOTES

[server:~] # cd /usr/src/sys/i386/conf/
 
[server:sys/i386/conf] # cp GENERIC KERN

[server:sys/i386/conf] # ee KERN 

[server:sys/i386/conf] # sed -E '/#.*device/d' KERN
# cpu           I486_CPU
# cpu           I586_CPU
cpu		I686_CPU
ident		GENERIC

makeoptions	DEBUG=-gdwarf-2		# Build kernel with gdb(1) debug symbols
makeoptions	WITH_CTF=1		# Run ctfconvert(1) for DTrace support

options 	SCHED_ULE		# ULE scheduler
options 	PREEMPTION		# Enable kernel thread preemption
options 	INET			# InterNETworking
# options 	INET6			# IPv6 communications protocols
options 	TCP_OFFLOAD		# TCP offload
options 	SCTP			# Stream Control Transmission Protocol
options 	FFS			# Berkeley Fast Filesystem
options 	SOFTUPDATES		# Enable FFS soft updates support
options 	UFS_ACL			# Support for access control lists
options 	UFS_DIRHASH		# Improve performance on big directories
options 	UFS_GJOURNAL		# Enable gjournal-based UFS journaling
options 	QUOTA			# Enable disk quotas for UFS
options 	NFSCL			# New Network Filesystem Client
options 	NFSD			# New Network Filesystem Server
options 	NFSLOCKD		# Network Lock Manager
options 	NFS_ROOT		# NFS usable as /, requires NFSCL
options 	MSDOSFS			# MSDOS Filesystem
options 	CD9660			# ISO 9660 Filesystem
options 	PROCFS			# Process filesystem (requires PSEUDOFS)
options 	PSEUDOFS		# Pseudo-filesystem framework
options 	GEOM_PART_GPT		# GUID Partition Tables.
options 	GEOM_RAID		# Soft RAID functionality.
options 	GEOM_LABEL		# Provides labelization
options 	COMPAT_FREEBSD4		# Compatible with FreeBSD4
options 	COMPAT_FREEBSD5		# Compatible with FreeBSD5
options 	COMPAT_FREEBSD6		# Compatible with FreeBSD6
options 	COMPAT_FREEBSD7		# Compatible with FreeBSD7
options 	SCSI_DELAY=5000		# Delay (in ms) before probing SCSI
options 	KTRACE			# ktrace(1) support
options 	STACK			# stack(9) support
options 	SYSVSHM			# SYSV-style shared memory
options 	SYSVMSG			# SYSV-style message queues
options 	SYSVSEM			# SYSV-style semaphores
options 	_KPOSIX_PRIORITY_SCHEDULING # POSIX P1003_1B real-time extensions
options 	PRINTF_BUFR_SIZE=128	# Prevent printf output being interspersed.
options 	KBD_INSTALL_CDEV	# install a CDEV entry in /dev
options 	HWPMC_HOOKS		# Necessary kernel hooks for hwpmc(4)
options 	AUDIT			# Security event auditing
options 	MAC			# TrustedBSD MAC Framework
options 	KDTRACE_HOOKS		# Kernel DTrace hooks
options 	INCLUDE_CONFIG_FILE     # Include this file in kernel
options 	KDB			# Kernel debugger related code
options 	KDB_TRACE		# Print a stack trace for a panic
options 	DDB_CTF			# kernel ELF linker loads CTF data

options 	ALTQ
options 	ALTQ_CBQ	# Class Based Queueing
options 	ALTQ_RED	# Random Early Detection
options 	ALTQ_RIO	# RED In/Out
options 	ALTQ_HFSC	# Hierarchical Packet Scheduler
options 	ALTQ_CDNR	# Traffic conditioner
options 	ALTQ_PRIQ	# Priority Queueing
options 	ALTQ_NOPCC	# Required if the TSC is unusable
options 	ALTQ_DEBUG

# To make an SMP kernel, the next two lines are needed
options 	SMP			# Symmetric MultiProcessor Kernel
device		apic			# I/O APIC

# CPU frequency control
device		cpufreq

# Bus support.
device		acpi
device		pci

# Floppy drives
device		fdc

# ATA controllers
device		ata		# Legacy ATA/SATA controllers
options 	ATA_CAM		# Handle legacy controllers with CAM

# SCSI Controllers
# options 	AHC_REG_PRETTY_PRINT	# Print register bitfields in debug
					# output.  Adds ~128k to driver.
# options 	AHD_REG_PRETTY_PRINT	# Print register bitfields in debug
					# output.  Adds ~215k to driver.

# ATA/SCSI peripherals
device		scbus		# SCSI bus (required for ATA/SCSI)
device		da		# Direct Access (disks)

# RAID controllers interfaced to the SCSI subsystem

# RAID controllers

# atkbdc0 controls both the keyboard and the PS/2 mouse
device		atkbdc		# AT keyboard controller
device		atkbd		# AT keyboard
device		psm		# PS/2 mouse

device		kbdmux		# keyboard multiplexer

device		vga		# VGA video card driver
options 	VESA		# Add support for VESA BIOS Extensions (VBE)

device		splash		# Splash screen and screen saver support

# syscons is the default console driver, resembling an SCO console
device		sc
options 	SC_PIXEL_MODE	# add support for the raster text mode

device		agp		# support several AGP chipsets

# Power management support (see NOTES for more options)
# Add suspend/resume support for the i8254.
device		pmtimer

# PCCARD (PCMCIA) support
# PCMCIA and cardbus bridge support

# Serial (COM) ports
device		uart		# Generic UART driver

# Parallel port

# PCI Ethernet NICs.

# PCI Ethernet NICs that use the common MII bus controller code.

# ISA Ethernet NICs.  pccard NICs included.

# Wireless NIC cards


device		loop		# Network loopback
options 	PADLOCK_RNG	# VIA Padlock RNG
options 	RDRAND_RNG	# Intel Bull Mountain RNG
device		ether		# Ethernet support
device		vlan		# 802.1Q VLAN support
device		tun		# Packet tunnel.
device		pty		# BSD-style compatibility pseudo ttys
device		md		# Memory "disks"
device		gif		# IPv6 and IPv4 tunneling
device		faith		# IPv6-to-IPv4 relaying (translation)
device		firmware	# firmware assist module

# Be aware of the administrative consequences of enabling this!
# Note that 'bpf' is required for DHCP.
device		bpf		# Berkeley packet filter

# USB support
options 	USB_DEBUG	# enable debug msgs
device		uhci		# UHCI PCI->USB interface
device		ohci		# OHCI PCI->USB interface
device		ehci		# EHCI PCI->USB interface (USB 2.0)
device		xhci		# XHCI PCI->USB interface (USB 3.0)
device		usb		# USB Bus (required)
device		uhid		# "Human Interface Devices"
device		ukbd		# Keyboard
device		ulpt		# Printer
device		umass		# Disks/Mass storage - Requires scbus and da
device		ums		# Mouse
device		urio		# Diamond Rio 500 MP3 player
device		u3g		# USB-based 3G modems (Option, Huawei, Sierra)
device		uark		# Technologies ARK3116 based serial adapters
device		ubsa		# Belkin F5U103 and compatible serial adapters
device		uftdi		# For FTDI usb serial adapters
device		uplcom		# Prolific PL-2303 serial adapters
device		uslcom		# SI Labs CP2101/CP2102 serial adapters
device		uvscom		# USB serial support for DDI pocket's PHS
# USB Ethernet, requires miibus
# # USB Wireless

# Sound support

# VirtIO support

device          pf
device          pflog
device          pfsync

# cat /etc/make.conf

...
MODULES_OVERRIDE = sound em

[server:sys/i386/conf] # cd /usr/src

[server:/usr/src] # make buildkernel KERNCONF=KERN

[server:/usr/src] # make installkernel KERNCONF=KERN

[server:/usr/src] # shutdown –r now

[server:~] # uname –a

В меню Loader выбираем пункт 6

OK unload kernel

OK load /boot/kernel.old/kernel
	или
OK load /boot/kernel.generic/kernel

OK boot