实现SPF垃圾邮件防护功能
SenderID （寄件人身份识别技术）。
SPF（SenderPolicyFramework，寄件人政策架构）。
SenderID技术与SPF一样，都是一种以IP（互联网协定）位址认证电子邮件寄件人身份的技术。
SenderID的创建向导地址是：http://www.microsoft.com/mscorp/safety/content/technologies/senderid/wizard/
要查看其他邮件域的SPF值，只需要在CMD下运行：
set type=txt
这里假如我们要查询163.com的SPF值，那么就键入163.com
会得到以下结果：
"v=spf1 ip4:220.181.12.0/22 ip4:202.108.9.128/25 ip4:202.108.5.0/24 ?all" 163.com nameserver = ns3.nease.net
163.com nameserver = ns.nease.net
ns.nease.net internet address = 202.106.185.75
ns3.nease.net internet address = 220.181.28.3
其中红色高亮部分就是SPF值，从这个值中我们可以得到163.com有效的邮件服务器是哪些。
FreeBSD：编译内核
FreeBSD安装后，内核中包含很多在实际环境中用不到的项目，所以可以重新修改编译内核来达到优化的效果。下面就是我的具体操作：
# cp GENERIC MAYTIDE （注释：MAYTIDE是我为这个新内核起的名字，你也可以根据自己的喜好命名。）
# ee MAYTIDE
我重新修改过的内核文件内容如下：
#
# GENERIC -- Generic kernel configuration file for FreeBSD/i386
#
# For more information on this file, please read the handbook section on
# Kernel Configuration Files:
#
# http://www.FreeBSD.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig-config.html
#
# The handbook is also available locally in /usr/share/doc/handbook
# if you've installed the doc distribution, otherwise always see the
# FreeBSD World Wide Web server (http://www.FreeBSD.org/) for the
# latest information.
#
# An exhaustive list of options and more detailed explanations of the
# device lines is also present in the ../../conf/NOTES and NOTES files.
# If you are in doubt as to the purpose or necessity of a line, check first
# in NOTES.
#
# $FreeBSD: src/sys/i386/conf/GENERIC,v 1.429.2.3.2.1 2005/10/28 19:22:41 jhb Exp $
machine i386
#cpu I486_CPU
#cpu I586_CPU
cpu I686_CPU
ident MAYTIDE
# To statically compile in device wiring instead of /boot/device.hints
#hints "GENERIC.hints" # Default places to look for devices.
makeoptions DEBUG=-g # Build kernel with gdb(1) debug symbols
#options SCHED_ULE # ULE scheduler
options SCHED_4BSD # 4BSD scheduler
options PREEMPTION # Enable kernel thread preemption
options INET # InterNETworking
options INET6 # IPv6 communications protocols
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 MD_ROOT # MD is a potential root device
#options NFSCLIENT # Network Filesystem Client
#options NFSSERVER # Network Filesystem Server
#options NFS_ROOT # NFS usable as /, requires NFSCLIENT
#options MSDOSFS # MSDOS Filesystem
options CD9660 # ISO 9660 Filesystem
options PROCFS # Process filesystem (requires PSEUDOFS)
options PSEUDOFS # Pseudo-filesystem framework
options GEOM_GPT # GUID Partition Tables.
options COMPAT_43 # Compatible with BSD 4.3 [KEEP THIS!]
options COMPAT_FREEBSD4 # Compatible with FreeBSD4
options COMPAT_FREEBSD5 # Compatible with FreeBSD5
options SCSI_DELAY=5000 # Delay (in ms) before probing SCSI
options KTRACE # ktrace(1) 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 KBD_INSTALL_CDEV # install a CDEV entry in /dev
#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.
options ADAPTIVE_GIANT # Giant mutex is adaptive.
device apic # I/O APIC
# Bus support.
#device eisa
device pci
# Floppy drives
#device fdc
# ATA and ATAPI devices
device ata
device atadisk # ATA disk drives
#device ataraid # ATA RAID drives
device atapicd # ATAPI CDROM drives
#device atapifd # ATAPI floppy drives
device atapist # ATAPI tape drives
options ATA_STATIC_ID # Static device numbering
# SCSI Controllers
#device ahb # EISA AHA1742 family
#device ahc # AHA2940 and onboard AIC7xxx devices
#device ahd # AHA39320/29320 and onboard AIC79xx devices
#device amd # AMD 53C974 (Tekram DC-390(T))
#device isp # Qlogic family
#device ispfw # Firmware for QLogic HBAs- normally a module
#device mpt # LSI-Logic MPT-Fusion
#device ncr # NCR/Symbios Logic
#device sym # NCR/Symbios Logic (newer chipsets + those of `ncr')
#device trm # Tekram DC395U/UW/F DC315U adapters
#device adv # Advansys SCSI adapters
#device adw # Advansys wide SCSI adapters
#device aha # Adaptec 154x SCSI adapters
#device aic # Adaptec 15[012]x SCSI adapters, AIC-6[23]60.
#device bt # Buslogic/Mylex MultiMaster SCSI adapters
#device ncv # NCR 53C500
#device nsp # Workbit Ninja SCSI-3
#device stg # TMC 18C30/18C50
# SCSI peripherals
#device scbus # SCSI bus (required for SCSI)
#device ch # SCSI media changers
#device da # Direct Access (disks)
#device sa # Sequential Access (tape etc)
#device cd # CD
#device pass # Passthrough device (direct SCSI access)
#device ses # SCSI Environmental Services (and SAF-TE)
# RAID controllers interfaced to the SCSI subsystem
#device amr # AMI MegaRAID
#device arcmsr # Areca SATA II RAID
#device asr # DPT SmartRAID V, VI and Adaptec SCSI RAID
#device ciss # Compaq Smart RAID 5*
#device dpt # DPT Smartcache III, IV - See NOTES for options
#device hptmv # Highpoint RocketRAID 182x
#device iir # Intel Integrated RAID
#device ips # IBM (Adaptec) ServeRAID
#device mly # Mylex AcceleRAID/eXtremeRAID
#device twa # 3ware 9000 series PATA/SATA RAID
# RAID controllers
#device aac # Adaptec FSA RAID
#device aacp # SCSI passthrough for aac (requires CAM)
#device ida # Compaq Smart RAID
#device mlx # Mylex DAC960 family
#device pst # Promise Supertrak SX6000
#device twe # 3ware ATA RAID
# 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 vga # VGA video card driver
device splash # Splash screen and screen saver support
# syscons is the default console driver, resembling an SCO console
device sc
# Enable this for the pcvt (VT220 compatible) console driver
#device vt
#options XSERVER # support for X server on a vt console
#options FAT_CURSOR # start with block cursor
device agp # support several AGP chipsets
# Power management support (see NOTES for more options)
#device apm
# Add suspend/resume support for the i8254.
device pmtimer
# PCCARD (PCMCIA) support
# PCMCIA and cardbus bridge support
#device cbb # cardbus (yenta) bridge
#device pccard # PC Card (16-bit) bus
#device cardbus # CardBus (32-bit) bus
# Serial (COM) ports
#device sio # 8250, 16[45]50 based serial ports
# Parallel port
#device ppc
#device ppbus # Parallel port bus (required)
#device lpt # Printer
#device plip # TCP/IP over parallel
#device ppi # Parallel port interface device
#device vpo # Requires scbus and da
# If you've got a "dumb" serial or parallel PCI card that is
# supported by the puc(4) glue driver, uncomment the following
# line to enable it (connects to the sio and/or ppc drivers):
#device puc
# PCI Ethernet NICs.
device de # DEC/Intel DC21x4x (``Tulip'')
device em # Intel PRO/1000 adapter Gigabit Ethernet Card
device ixgb # Intel PRO/10GbE Ethernet Card
device txp # 3Com 3cR990 (``Typhoon'')
device vx # 3Com 3c590, 3c595 (``Vortex'')
# PCI Ethernet NICs that use the common MII bus controller code.
# NOTE: Be sure to keep the 'device miibus' line in order to use these NICs!
device miibus # MII bus support
device bfe # Broadcom BCM440x 10/100 Ethernet
device bge # Broadcom BCM570xx Gigabit Ethernet
device dc # DEC/Intel 21143 and various workalikes
device fxp # Intel EtherExpress PRO/100B (82557, 82558)
device lge # Level 1 LXT1001 gigabit Ethernet
device nge # NatSemi DP83820 gigabit Ethernet
device nve # nVidia nForce MCP on-board Ethernet Networking
device pcn # AMD Am79C97x PCI 10/100(precedence over 'lnc')
device re # RealTek 8139C+/8169/8169S/8110S
device rl # RealTek 8129/8139
device sf # Adaptec AIC-6915 (``Starfire'')
device sis # Silicon Integrated Systems SiS 900/SiS 7016
device sk # SysKonnect SK-984x & SK-982x gigabit Ethernet
device ste # Sundance ST201 (D-Link DFE-550TX)
device ti # Alteon Networks Tigon I/II gigabit Ethernet
device tl # Texas Instruments ThunderLAN
device tx # SMC EtherPower II (83c170 ``EPIC'')
device vge # VIA VT612x gigabit Ethernet
device vr # VIA Rhine, Rhine II
device wb # Winbond W89C840F
device xl # 3Com 3c90x (``Boomerang'', ``Cyclone'')
# ISA Ethernet NICs. pccard NICs included.
device cs # Crystal Semiconductor CS89x0 NIC
# 'device ed' requires 'device miibus'
device ed # NE[12]000, SMC Ultra, 3c503, DS8390 cards
device ex # Intel EtherExpress Pro/10 and Pro/10+
device ep # Etherlink III based cards
device fe # Fujitsu MB8696x based cards
device ie # EtherExpress 8/16, 3C507, StarLAN 10 etc.
device lnc # NE2100, NE32-VL Lance Ethernet cards
device sn # SMC's 9000 series of Ethernet chips
device xe # Xircom pccard Ethernet
# ISA devices that use the old ISA shims
#device le
# Wireless NIC cards
#device wlan # 802.11 support
#device an # Aironet 4500/4800 802.11 wireless NICs.
#device awi # BayStack 660 and others
#device ral # Ralink Technology RT2500 wireless NICs.
#device wi # WaveLAN/Intersil/Symbol 802.11 wireless NICs.
#device wl # Older non 802.11 Wavelan wireless NIC.
# Pseudo devices.
device loop # Network loopback
device random # Entropy device
device ether # Ethernet support
device sl # Kernel SLIP
device ppp # Kernel PPP
device tun # Packet tunnel.
device pty # Pseudo-ttys (telnet etc)
device md # Memory "disks"
device gif # IPv6 and IPv4 tunneling
device faith # IPv6-to-IPv4 relaying (translation)
# The `bpf' device enables the Berkeley Packet Filter.
# Be aware of the administrative consequences of enabling this!
# Note that 'bpf' is required for DHCP.
device bpf # Berkeley packet filter
# USB support
#device uhci # UHCI PCI->USB interface
#device ohci # OHCI PCI->USB interface
#device ehci # EHCI PCI->USB interface (USB 2.0)
#device usb # USB Bus (required)
#device udbp # USB Double Bulk Pipe devices
#device ugen # Generic
#device uhid # "Human Interface Devices"
#device ukbd # Keyboard
#device ulpt # Printer
#device umass # Disks/Mass storage - Requires scbus and da
#device ums # Mouse
#device ural # Ralink Technology RT2500USB wireless NICs
#device urio # Diamond Rio 500 MP3 player
#device uscanner # Scanners
# USB Ethernet, requires miibus
#device aue # ADMtek USB Ethernet
#device axe # ASIX Electronics USB Ethernet
#device cdce # Generic USB over Ethernet
#device cue # CATC USB Ethernet
#device kue # Kawasaki LSI USB Ethernet
#device rue # RealTek RTL8150 USB Ethernet
# FireWire support
#device firewire # FireWire bus code
#device sbp # SCSI over FireWire (Requires scbus and da)
#device fwe # Ethernet over FireWire (non-standard!)
编辑好内核后就可以编译安装这个新内核。
# cd ../compile/MAYTIDE
# make depend
# make
# make install
编译安装完成后重新启动，就会发现系统使用的是新的内核了。
我在虚拟机种编译感觉CPU占用率特别高，整个过程用了近1个小时。
FreeBSD：安装CVSUP并更新代码和PORTS树
什么是CVSup?
CVSup 是一个用于从远程服务器主机上的主cvs(1) 库分发和更新源码树的软件包。OpenBSD源码的维护，用的是位于加拿大的一个中心开发机器上的CVS库。通过使用CVSup，OpenBSD用户可以很简单的让他们自己的源码树保持最新。
CVSup使用所谓拉模式的更新方式。在拉模式作用下，客户在需要的时候，询问服务器以获取更新。服务器被动的等待它的客户发出更新请求。因而，所有等更新由客户端发起，服务器从不主动发送更新请求。用户必须手动运行CVSup客户端来获取更新，或者设置一个cron(8) 作业定期自动运行。
术语CVSup，大写表示，指代整个软件包。它的主要组件是运行于客户端机器的cvsup，还有运行在每个OpenBSD CVSup站点的服务器端 cvsupd 。
CVSup被设计为比sup(1)更快速和灵活，并且是它的替代软件。
OpenBSD项目当前有五个主要的源码库：
- src - 存放OpenBSD操作系统的所有源码。
- ports - 存放OpenBSD Ports。
- www - 存放所有OpenBSD web页(包括现在这个)。
- x11 - 存放OpenBSD对XFree86-3 软件计划的改编版本。
- xf4 - 存放OpenBSD对XFree86-4 软件计划的改编版本。
什么是CVS?
CVS是用于管理OpenBSD源码树的源码控制系统。详细说明请参考这里。注意CVS和CVSup是完全不同的程序。 尽管CVS可被用作远程文件访问，但没有对大规模的网络源码发布作优化，而CVSup对完成这样的任务更有效。
以下是我的学到的安装、配置和使用：
1、安装CVSUP
这里我通过网络来安装cvsup，使用命令：
2、配置CVSUP
配置CVSUP主要是指定索要使用的CVSUP服务器地址及配置选择性的更新。
# ee standard-supfile
将“*host=”后面的地址更换为你连接最快的服务器，我找到的是“cvsup4.freebsdchina.org”
# ee ports-supfile
将“*host=”后面的地址更换为你连接最快的服务器，我找到的是“cvsup4.freebsdchina.org”
# reboot 重新启动计算机。
3、升级源代码
# cvsup -g -L 2 standard-supfile
之后再升级PORTS树
# cvsup -g -L 2 Ports-supfile
以上便完成了CVSUP的安装、配置和升级，在完成这篇Blog时我的升级还没有完成，郁闷！看来编译优化内核要放到明天了。
