前言
Zebra是一个路由软件包，提供基于TCP/IP路由服务，支持RIPv1, RIPv2, RIPng, OSPFv2, OSPFv3, BGP- 4,
和 BGP-4+等众多路由协议。Zebra还支持BGP特性路由反射器（Route Reflector）。除了传统的 IPv4路由协议
，Zebra也支持IPv6路由协议。如果运行的SNMP守护进程（需要ucd-snmp）支持SMUX协 议，Zebra还能支持路由
协议MIBs。
由以上可见，Zebra的确是一个很不错的路由系统，但比起真正的路由器就简直是小儿科，所以网络高手 就当
这文章是小孩子过家家吧，而对于象我这样的初学者（特别是没有真实设备或足够设备进行实验） 也不失为一
个学习和熟悉路由配置、路由协议的好工具。我没有实际的配置经验，对路由的技术细节也 不是十分清晰，完
全是在扔破砖头。希望路由高手指正概念错误。
安装
Zebra目前最新的版本是0.92a，它的安装非常简单，我们只需从http://www.zebra.org/下载zebra-
0.92a.tar.gz，然后执行以下命令安装（本文环境是RedHat7.2）：
shell> tar xzf zebra-0.92a.tar.gz
shell> cd zebra-0.92a
shell> ./configure
shell> make
shell> make install
shell> cd zebra-0.92a
shell> ./configure
shell> make
shell> make install
这样Zebra就安装好了，安装的执行文件：
shell> ls /usr/local/sbin
bgpd ospfd ripd zebra
bgpd ospfd ripd zebra
配置文件：
shell> ls /usr/local/etc
bgpd.conf.sample ospfd.conf.sample zebra.conf.sample
bgpd.conf.sample2 ripd.conf.sample
bgpd.conf.sample ospfd.conf.sample zebra.conf.sample
bgpd.conf.sample2 ripd.conf.sample
运行
编译安装完Zebra后，可以看到有4个可执行文件和5个配置样本文件，我们就使用它的配置样本文件：
shell> cd /usr/local/etc
shell> cp zebra.conf.sample zebra.conf
shell> cp zebra.conf.sample zebra.conf
Zebra的各进程有各自的终端接口或VTY，如果我们需要给连接到它们的端口设置别名的话，在/etc/ services
文件添加如下内容：
zebrasrv 2600/tcp # zebra service
zebra 2601/tcp # zebra vty
ripd 2602/tcp # RIPd vty
ripngd 2603/tcp # RIPngd vty
ospfd 2604/tcp # OSPFd vty
bgpd 2605/tcp # BGPd vty
ospf6d 2606/tcp # OSPF6d vty
zebra 2601/tcp # zebra vty
ripd 2602/tcp # RIPd vty
ripngd 2603/tcp # RIPngd vty
ospfd 2604/tcp # OSPFd vty
bgpd 2605/tcp # BGPd vty
ospf6d 2606/tcp # OSPF6d vty
然后就可以启动Zebra了：
shell> zebra -d
这样，Zebra就以守护进程启动了，其它的参数请参考zebra -h。
基本路由配置命令
直接用telnet连接：
shell> telnet localhost 2601
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Hello, this is zebra (version 0.92a).
Copyright 1996-2001 Kunihiro Ishiguro.
Copyright 1996-2001 Kunihiro Ishiguro.
User Access Verification
Password:
Zebra会提示输入口令，我们通过/usr/local/etc/zebra.conf可以看到口令是zebra，enable口令也是zebra。
输 入口令zebra，得到路由器用户模式提示符：
Router>
进入特权模式：
Router> en
Password:
Router#
Password:
Router#
输入一个问号，看看Zebra提供了多少路由命令：
Router# ?
configure Configuration from vty interface
copy Copy configuration
debug Debugging functions (see also 'undebug')
disable Turn off privileged mode command
end End current mode and change to enable mode.
exit Exit current mode and down to previous mode
help Description of the interactive help system
list Print command list
no Negate a command or set its defaults
quit Exit current mode and down to previous mode
show Show running system information
terminal Set terminal line parameters
who Display who is on vty
write Write running configuration to memory, network, or terminal
configure Configuration from vty interface
copy Copy configuration
debug Debugging functions (see also 'undebug')
disable Turn off privileged mode command
end End current mode and change to enable mode.
exit Exit current mode and down to previous mode
help Description of the interactive help system
list Print command list
no Negate a command or set its defaults
quit Exit current mode and down to previous mode
show Show running system information
terminal Set terminal line parameters
who Display who is on vty
write Write running configuration to memory, network, or terminal
提供的命令很少，实际路由器好多命令都没有，我们只能用有限的命令投入到无限的实验中去。
Router# sh run
Current configuration:
!
hostname Router
password zebra
enable password zebra
!
interface lo
!
interface eth0
!
line vty
!
end
!
hostname Router
password zebra
enable password zebra
!
interface lo
!
interface eth0
!
line vty
!
end
Zebra把操作系统的网络接口当做路由器的接口，所以在做比较复杂的路由实验，会需要比较多的网卡。
进入全局模式，尽可能把实际可用的配置命令都实验一遍：
Router# conf t
Router(config)#
Router(config)#
自己取一个路由器名字：
Router(config)# hostname r1
r1(config)#
r1(config)#
Zebra比较简单，登陆口令不是在line下修改，而是直接在全局模式下用password修改
r1(config)# password {password}
Zebra不支持enable secret {password}这种MD5加密口令，只能使用enable password {password}来修改
enable口令：
r1# conf t
r1(config)# enable password {password}
r1(config)# enable password {password}
在路由器配置中加密所有的口令：
r1(config)# service password-encryption
回到特权模式：
r1(config)# exit
r1# sh run
r1# sh run
Current configuration:
!
hostname r1
password 8 alA5.vcyMAwXQ
enable password 8 ksbxOFN8xcFMc
service password-encryption
!
interface lo
!
interface eth0
!
line vty
!
end
!
hostname r1
password 8 alA5.vcyMAwXQ
enable password 8 ksbxOFN8xcFMc
service password-encryption
!
interface lo
!
interface eth0
!
line vty
!
end
我们看到刚才的明文密码都进行加密了，给我们的实验机也提高安全性。Zebra有一点比较恶心，如果我 们先
设置了service password-encryption，然后再修改口令，sh run就发现口令又都是明文的了，但是由 于有
service password-encryption，所以就无法登陆了。
去掉会话超时，免得10分钟没有动作，就把我们给踢了。但是在实际的路由器配置中，为安全起见我们 最好还
是设上会话超时。
r1# conf t
r1(config)# line vty
r1(config-line)# exec-timeout 0 0
r1(config)# line vty
r1(config-line)# exec-timeout 0 0
设置日志记录，Zebra可以把日志记录到标准输出、syslog、以及指定输出文件：
r1(config-line)# exit
r1(config)# log stdout
r1(config)# no log stdout
r1(config)# log syslog
r1(config)# no log syslog
r1(config)# log file /usr/local/etc/zebra.log
r1(config)# log stdout
r1(config)# no log stdout
r1(config)# log syslog
r1(config)# no log syslog
r1(config)# log file /usr/local/etc/zebra.log
配置接口IP地址：
r1(config)# int lo
r1(config-if)# ip address 127.0.0.1/8
r1(config-if)# exit
r1(config)# int eth0
r1(config-if)# ip address 192.168.5.121/24
r1(config-if)# ip address 127.0.0.1/8
r1(config-if)# exit
r1(config)# int eth0
r1(config-if)# ip address 192.168.5.121/24
Zebra比较奇怪，不能使用ip address 192.168.5.121 255.255.255.0这种形式设置IP。测试一下，就设置成
和Linux中使用的一样。
保存我们刚才的配置：
r1(config-if)# exit
r1(config)# exit
r1# copy run start
Configuration saved to /usr/local/etc/zebra.conf
r1#
r1(config)# exit
r1# copy run start
Configuration saved to /usr/local/etc/zebra.conf
r1#
2、用Zebra做简单的RIP实验
RIP是应用较早、使用较普遍的IGP，适用于小型同类网络，是典型的距离向量(distance-vector)协 议。RIP通
过广播UDP报文来交换路由信息，每30秒发送一次路由信息更新。RIP提供跳跃计数(hop count)作为尺度来衡量
路由距离，跳跃计数是一个包到达目标所必须经过的路由器的数目。如果到相同 目标有二个不等速或不同带宽
的路由器，但跳跃计数相同，则RIP认为两个路由是等距离的。RIP最多支 持的跳数为15，即在源和目的网间所
要经过的最多路由器的数目为15，跳数16表示不可达。RIPv2支持 验证、密钥管理、路由汇总、无类域间路由
(CIDR)和变长子网掩码(VLSMs)。
Zebra支持RIPv2，使用ripd程序实现RIP路由功能，但ripd程序需要在zebra程序读取接口信息，所以zebra 一
定要在ripd之前启动。由于条件所限，下面的RIP实验是在两台单网卡的RedHat7.2下做的，所以只是 最简单的
演示。
按照上面基本配置的方法初始化第一台机器：
shell_1> cd /usr/local/etc
shell_1> cp zebra.conf.sample zebra.conf
shell_1> cp ripd.conf.sample ripd.conf
shell_1> zebra -d
shell_1> cp zebra.conf.sample zebra.conf
shell_1> cp ripd.conf.sample ripd.conf
shell_1> zebra -d
进入zebra设置IP
shell_1> telnet localhost 2601
Password:
Router> en
Password:
Router# conf t
Router(config)# hostname r1
r1(config)# int eth0
r1(config-if)# ip address 192.168.5.121/24
r1(config-if)# ctrl+z
r1# copy run start
Password:
Router> en
Password:
Router# conf t
Router(config)# hostname r1
r1(config)# int eth0
r1(config-if)# ip address 192.168.5.121/24
r1(config-if)# ctrl+z
r1# copy run start
进入第一台机器的rip设置
shell_1> ripd -d
shell_1> telnet localhost 2602
Password:
ripd> en
ripd# conf t
ripd(config)# hostname r1_ripd !改个名字好辨认
r1_ripd(config)# router rip !启动rip
r1_ripd(config-router)# network 192.168.5.0/24 !RIPv1是有类别路由协议，RIPv2是无类别路由协议，
shell_1> telnet localhost 2602
Password:
ripd> en
ripd# conf t
ripd(config)# hostname r1_ripd !改个名字好辨认
r1_ripd(config)# router rip !启动rip
r1_ripd(config-router)# network 192.168.5.0/24 !RIPv1是有类别路由协议，RIPv2是无类别路由协议，
Zebra 默认支持RIPv2，指定网络需要子网掩码。
r1的RIP简单配置这样就可用了，下面来检验一下：
r1_ripd# sh ip protocols
Routing Protocol is "rip"
Sending updates every 30 seconds with +/-50%, next due in 3 seconds
Timeout after 180 seconds, garbage collect after 120 seconds
Outgoing update filter list for all interface is not set
Incoming update filter list for all interface is not set
Default redistribution metric is 1
Redistributing:
Default version control: send version 2, receive version 2
Interface Send Recv Key-chain
eth0 2 2
Routing for Networks:
192.168.5.0/24
Routing Information Sources:
Gateway BadPackets BadRoutes Distance Last Update
Distance: (default is 120)
Routing Protocol is "rip"
Sending updates every 30 seconds with +/-50%, next due in 3 seconds
Timeout after 180 seconds, garbage collect after 120 seconds
Outgoing update filter list for all interface is not set
Incoming update filter list for all interface is not set
Default redistribution metric is 1
Redistributing:
Default version control: send version 2, receive version 2
Interface Send Recv Key-chain
eth0 2 2
Routing for Networks:
192.168.5.0/24
Routing Information Sources:
Gateway BadPackets BadRoutes Distance Last Update
Distance: (default is 120)
我们看到RIP已经起来了，是RIPv2。
r1_ripd# sh ip rip
Codes: R - RIP, C - connected, O - OSPF, B - BGP
Codes: R - RIP, C - connected, O - OSPF, B - BGP
Network Next Hop Metric From Time
由于就两个接口直连，没有其它网络，所以sh ip rip看不到什么。
Zebra对log处理可能有些问题，使用log stdout不能显示各种debug信息，所以只能记录到文件，在shell下 用
tail命令查看。
r1_ripd# debug rip events
r1_ripd# debug rip packet
r1_ripd(config)# log file /usr/local/etc/ripd.log
r1_ripd# debug rip packet
r1_ripd(config)# log file /usr/local/etc/ripd.log
然后我们在shell下查看debug信息
shell_1> tail -f /usr/local/etc/ripd.log
--------------------------------8<---------------------------------------
2002/04/28 22:17:44 RIP: update timer fire!
2002/04/28 22:17:44 RIP: SEND UPDATE to eth0 ifindex 2
2002/04/28 22:17:44 RIP: multicast announce on eth0
2002/04/28 22:17:44 RIP: update routes on interface eth0 ifindex 2
2002/04/28 22:18:23 RIP: update timer fire!
2002/04/28 22:18:23 RIP: SEND UPDATE to eth0 ifindex 2
2002/04/28 22:18:23 RIP: multicast announce on eth0
2002/04/28 22:18:23 RIP: update routes on interface eth0 ifindex 2
2002/04/28 22:19:04 RIP: update timer fire!
2002/04/28 22:19:04 RIP: SEND UPDATE to eth0 ifindex 2
2002/04/28 22:19:04 RIP: multicast announce on eth0
2002/04/28 22:19:04 RIP: update routes on interface eth0 ifindex 2
--------------------------------8<---------------------------------------
--------------------------------8<---------------------------------------
2002/04/28 22:17:44 RIP: update timer fire!
2002/04/28 22:17:44 RIP: SEND UPDATE to eth0 ifindex 2
2002/04/28 22:17:44 RIP: multicast announce on eth0
2002/04/28 22:17:44 RIP: update routes on interface eth0 ifindex 2
2002/04/28 22:18:23 RIP: update timer fire!
2002/04/28 22:18:23 RIP: SEND UPDATE to eth0 ifindex 2
2002/04/28 22:18:23 RIP: multicast announce on eth0
2002/04/28 22:18:23 RIP: update routes on interface eth0 ifindex 2
2002/04/28 22:19:04 RIP: update timer fire!
2002/04/28 22:19:04 RIP: SEND UPDATE to eth0 ifindex 2
2002/04/28 22:19:04 RIP: multicast announce on eth0
2002/04/28 22:19:04 RIP: update routes on interface eth0 ifindex 2
--------------------------------8<---------------------------------------
RIP每隔30秒发送一次更新，在sh ip prot可以看到Sending updates every 30 seconds with +/-50%
第二台机器的设置
前面的初始化和第一台一样，不过这里名字设成r2便于辨认，IP设成了192.168.5.123/24。
进入第二台机器的rip设置
shell_2> ripd -d
shell_2> telnet localhost 2602
Password:
ripd> en
ripd# conf t
ripd(config)# hostname r2_ripd
r2_ripd(config)# router rip
r2_ripd(config-router)# network 192.168.5.0/24
shell_2> telnet localhost 2602
Password:
ripd> en
ripd# conf t
ripd(config)# hostname r2_ripd
r2_ripd(config)# router rip
r2_ripd(config-router)# network 192.168.5.0/24
执行完network命令，我们看到第一台机器的tail -f /usr/local/etc/ripd.log输出下面的信息：
--------------------------------8<---------------------------------------
2002/04/28 22:19:15 RIP: RECV packet from 192.168.5.123 port 520 on eth0
2002/04/28 22:19:15 RIP: RECV REQUEST version 2 packet size 24
2002/04/28 22:19:15 RIP: 0.0.0.0/0 -> 0.0.0.0 family 0 tag 0 metric 16
2002/04/28 22:19:15 RIP: update routes to neighbor 192.168.5.123
2002/04/28 22:19:35 RIP: update timer fire!
2002/04/28 22:19:35 RIP: SEND UPDATE to eth0 ifindex 2
2002/04/28 22:19:35 RIP: multicast announce on eth0
2002/04/28 22:19:35 RIP: update routes on interface eth0 ifindex 2
--------------------------------8<---------------------------------------
2002/04/28 22:19:15 RIP: RECV packet from 192.168.5.123 port 520 on eth0
2002/04/28 22:19:15 RIP: RECV REQUEST version 2 packet size 24
2002/04/28 22:19:15 RIP: 0.0.0.0/0 -> 0.0.0.0 family 0 tag 0 metric 16
2002/04/28 22:19:15 RIP: update routes to neighbor 192.168.5.123
2002/04/28 22:19:35 RIP: update timer fire!
2002/04/28 22:19:35 RIP: SEND UPDATE to eth0 ifindex 2
2002/04/28 22:19:35 RIP: multicast announce on eth0
2002/04/28 22:19:35 RIP: update routes on interface eth0 ifindex 2
--------------------------------8<---------------------------------------
r1通过UDP广播接收到192.168.5.123的更新包，并且把192.168.5.123设为neighbor。
保存一下配置
r1_ripd# copy run start
Configuration saved to /usr/local/etc/ripd.conf
r2_ripd# copy run start
Configuration saved to /usr/local/etc/ripd.conf
Configuration saved to /usr/local/etc/ripd.conf
r2_ripd# copy run start
Configuration saved to /usr/local/etc/ripd.conf
Zebra还支持很多RIP功能，如果Filtering RIP Routes, RIP route-map, RIP Authentication等，有条件有时
间 的话可以做更复杂的实验。
3、用Zebra做OSPF实验
OSPF（开放最短路径优先）路由协议是一项链路状态型技术，是目前IGP中应用最广、性能最优的一个 协议，
解决了RIP不能解决的大型、可扩展的网络需求而写的，适用于大规模的网络。
Zebra支持OSPFv2和OSPFv3（用于IPv6的OSPF，CISCO还未对其封装），由于条件所限，下面的OSPF实 验同样是
在两台单网卡的RedHat7.2下做的。
Zebra使用ospfd程序实现OSPF路由功能，但ospfd需要从zebra程序获得接口信息，所以zebra程序必须在 ospfd
程序之前运行。ospfd不支持多个OSPF进程，我们不能指定OSPF进程号。
初始化第一台机器：
shell_1> cd /usr/local/etc
shell_1> cp zebra.conf.sample zebra.conf
shell_1> cp ospfd.conf.sample ospfd.conf
shell_1> zebra -d
shell_1> cp zebra.conf.sample zebra.conf
shell_1> cp ospfd.conf.sample ospfd.conf
shell_1> zebra -d
进入zebra设置IP
shell_1> telnet localhost 2601
Password:
Router> en
Password:
Router# conf t
Router(config)# hostname r1
r1(config)# int eth0
r1(config-if)# ip address 192.168.5.121/24
r1(config-if)# ctrl+z
r1# copy run start
Password:
Router> en
Password:
Router# conf t
Router(config)# hostname r1
r1(config)# int eth0
r1(config-if)# ip address 192.168.5.121/24
r1(config-if)# ctrl+z
r1# copy run start
进入第一台机器的ospf设置
shell_1> ospfd -d
shell_1> telnet localhost 2604
Password:
ospfd> en
ospfd# conf t
ospfd(config)# hostname r1_ospfd !改个名字好辨认
r1_ospfd(config)# router ospf !启动ospf
r1_ospfd(config-router)# ospf router-id 192.168.5.121 !设置router-id
r1_ospfd(config-router)# network 192.168.5.0/24 area 0
!最关键的，来标识路由器上哪些IP网络号是OSPF的一部分，对于每个网络，我们必须标识该网络所属 的区域
shell_1> telnet localhost 2604
Password:
ospfd> en
ospfd# conf t
ospfd(config)# hostname r1_ospfd !改个名字好辨认
r1_ospfd(config)# router ospf !启动ospf
r1_ospfd(config-router)# ospf router-id 192.168.5.121 !设置router-id
r1_ospfd(config-router)# network 192.168.5.0/24 area 0
!最关键的，来标识路由器上哪些IP网络号是OSPF的一部分，对于每个网络，我们必须标识该网络所属 的区域
。由于我们只有两台机器，当然只有一个网络，所以只需执行一个network命令就够了。
对于我们的小网络，ospf就算配好了，下面来检验一下：
r1_ospfd(config-router)# ctrl+z
r1_ospfd# sh ip ospf route
============ OSPF network routing table ============
N 192.168.5.0/24 [10] area: 0.0.0.0
directly attached to eth0
r1_ospfd# sh ip ospf route
============ OSPF network routing table ============
N 192.168.5.0/24 [10] area: 0.0.0.0
directly attached to eth0
============ OSPF router routing table =============
============ OSPF external routing table ===========
r1_ospfd# sh ip ospf database
OSPF Router with ID (192.168.5.121)
Router Link States (Area 0.0.0.0)
Link ID ADV Router Age Seq# CkSum Link count
192.168.5.121 192.168.5.121 126 0x80000002 0x8584 1
192.168.5.121 192.168.5.121 126 0x80000002 0x8584 1
r1_ospfd# sh ip ospf int eth0
eth0 is up, line protocol is up
eth0 is up, line protocol is up
Internet Address 192.168.5.121/24, Area 0.0.0.0
Router ID 192.168.5.121, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 192.168.5.121, Interface Address 192.168.5.121
No backup designated router on this network
Timer intarvals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Neighbor Count is 0, Adjacent neighbor count is 0
Router ID 192.168.5.121, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 192.168.5.121, Interface Address 192.168.5.121
No backup designated router on this network
Timer intarvals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:07
Neighbor Count is 0, Adjacent neighbor count is 0
由于网络里没有其它的路由器，r1就把自己选为DR（指定路由器）了。Zebra对log处理可能有些问题，使 用
log stdout不能显示各种debug信息，所以只能记录到文件，在shell下用tail命令查看。而且debug命令和 实
际路由器也有不同。
r1_ospfd# debug ospf event
r1_ospfd(config)# log file /usr/local/etc/ospfd.log
r1_ospfd(config)# log file /usr/local/etc/ospfd.log
然后我们在shell下查看debug信息
shell_1> tail -f /usr/local/etc/ospfd.log
--------------------------------8<---------------------------------------
2002/04/28 14:24:27 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 14:24:37 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 14:24:47 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 14:24:57 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 14:25:07 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
--------------------------------8<---------------------------------------
--------------------------------8<---------------------------------------
2002/04/28 14:24:27 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 14:24:37 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 14:24:47 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 14:24:57 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 14:25:07 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
--------------------------------8<---------------------------------------
我们错过了最开始的信息，看到路由器每隔10秒发送一个hello数据包。hello数据包通过多目组播地址
224.0.0.5被发送出去，如果我们打开debug ospf packet all就能很清楚的看到。
第二台机器的设置
前面的初始化和第一台一样，不过这里名字设成r2便于辨认，IP设成了192.168.5.123/24。
进入第二台机器的ospf设置
shell_2> ospfd -d
shell_2> telnet localhost 2604
Password:
ospfd> en
ospfd# conf t
ospfd(config)# hostname r2_ospfd
r2_ospfd(config)# router ospf
r2_ospfd(config-router)# ospf router-id 192.168.5.123
r2_ospfd(config-router)# network 192.168.5.0/24 area 0
shell_2> telnet localhost 2604
Password:
ospfd> en
ospfd# conf t
ospfd(config)# hostname r2_ospfd
r2_ospfd(config)# router ospf
r2_ospfd(config-router)# ospf router-id 192.168.5.123
r2_ospfd(config-router)# network 192.168.5.0/24 area 0
执行完network命令，我们看到第一台机器的tail -f /usr/local/etc/ospfd.log输出下面的信息：
--------------------------------8<---------------------------------------
2002/04/28 14:25:51 OSPF: Packet 192.168.5.123 [Hello:RECV]: Options *|*|-|-|-|-|E|*
2002/04/28 14:25:51 OSPF: NSM[eth0:192.168.5.121:0.0.0.0]: start
2002/04/28 14:25:52 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 14:25:52 OSPF: couldn't find any VL to associate the packet with
2002/04/28 14:25:52 OSPF: DR-Election[1st]: Backup 192.168.5.123
2002/04/28 14:25:52 OSPF: DR-Election[1st]: DR 192.168.5.121
2002/04/28 14:25:52 OSPF: Packet[DD]: Negotiation done (Slave).
--------------------------------8<---------------------------------------
2002/04/28 14:25:51 OSPF: Packet 192.168.5.123 [Hello:RECV]: Options *|*|-|-|-|-|E|*
2002/04/28 14:25:51 OSPF: NSM[eth0:192.168.5.121:0.0.0.0]: start
2002/04/28 14:25:52 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 14:25:52 OSPF: couldn't find any VL to associate the packet with
2002/04/28 14:25:52 OSPF: DR-Election[1st]: Backup 192.168.5.123
2002/04/28 14:25:52 OSPF: DR-Election[1st]: DR 192.168.5.121
2002/04/28 14:25:52 OSPF: Packet[DD]: Negotiation done (Slave).
--------------------------------8<---------------------------------------
r1收到r2(192.168.5.123)发过来的hello数据包，交换信息后选举DR，由于本身192.168.5.121是DR了，所以
只选举了BDR就好了。这时在r1上就能看到r2了。
r1_ospfd# sh ip ospf neig
Neighbor ID Pri State Dead Time Address Interface RXmtL
RqstL DBsmL
192.168.5.123 1 Full/Backup 00:00:37 192.168.5.123 eth0:192.168.5.121 0 0
192.168.5.123 1 Full/Backup 00:00:37 192.168.5.123 eth0:192.168.5.121 0 0
0
检验其它信息
r1_ospfd# sh ip ospf database
OSPF Router with ID (192.168.5.121)
Router Link States (Area 0.0.0.0)
Link ID ADV Router Age Seq# CkSum Link count
192.168.5.121 192.168.5.121 1259 0x80000008 0x534e 1
192.168.5.123 192.168.5.123 1265 0x80000006 0x534a 1
192.168.5.121 192.168.5.121 1259 0x80000008 0x534e 1
192.168.5.123 192.168.5.123 1265 0x80000006 0x534a 1
Net Link States (Area 0.0.0.0)
Link ID ADV Router Age Seq# CkSum
192.168.5.123 192.168.5.123 1265 0x80000001 0x5a5a
192.168.5.123 192.168.5.123 1265 0x80000001 0x5a5a
r1_ospfd# sh ip ospf int eth0
eth0 is up, line protocol is up
eth0 is up, line protocol is up
Internet Address 192.168.5.121/24, Area 0.0.0.0
Router ID 192.168.5.121, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 192.168.5.121, Interface Address 192.168.5.121
Backup Designated Router (ID) 192.168.5.123, Interface Address 192.168.5.123
Timer intarvals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Neighbor Count is 1, Adjacent neighbor count is 1
Router ID 192.168.5.121, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 192.168.5.121, Interface Address 192.168.5.121
Backup Designated Router (ID) 192.168.5.123, Interface Address 192.168.5.123
Timer intarvals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Neighbor Count is 1, Adjacent neighbor count is 1
和前面的输出信息相比，发生了很多变化，两台路由器已经相互识别了。OSPF不象RIP一样，每隔30秒 给所有
的邻居广播一次完整的路由表，而是通过IP多目组播地址224.0.0.5每隔10秒发送一个很小的hello 数据包来维
护邻居关系，当链路发生变化的时候，才重新计算。
拔掉两台机器连接的网线，看ospfd.log的记录：
--------------------------------8<---------------------------------------
2002/04/28 16:25:53 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 16:25:57 OSPF: Packet 192.168.5.123 [Hello:RECV]: Options *|*|-|-|-|-|E|*
2002/04/28 16:26:03 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 16:26:13 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 16:26:23 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 16:26:33 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): Start
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): looked through areas
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): bb_configured: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): bb_act_attached: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): areas_configured: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): areas_act_attached: 1
2002/04/28 16:26:37 OSPF: nsm_change_status(): scheduling new router-LSA origination
2002/04/28 16:26:37 OSPF: DR-Election[1nd]: Backup 0.0.0.0
2002/04/28 16:26:37 OSPF: DR-Election[1nd]: DR 192.168.5.121
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): Start
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): looked through areas
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): bb_configured: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): bb_act_attached: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): areas_configured: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): areas_act_attached: 1
2002/04/28 16:26:37 OSPF: Timer[router-LSA]: (router-LSA Refresh expire)
2002/04/28 16:26:37 OSPF: counting fully adjacent virtual neighbors in area 0.0.0.0
2002/04/28 16:26:37 OSPF: there are 0 of them
2002/04/28 16:26:37 OSPF: SPF: calculation timer scheduled
2002/04/28 16:26:37 OSPF: SPF: calculation timer delay = 5
2002/04/28 16:26:37 OSPF: ospf_flood_through_interface(): considering int eth0:192.168.5.121
2002/04/28 16:26:37 OSPF: ospf_flood_through_interface(): considering nbr 192.168.5.121
2002/04/28 16:26:42 OSPF: SPF: Timer (SPF calculation expire)
2002/04/28 16:26:42 OSPF: ospf_spf_calculate: Start
2002/04/28 16:26:42 OSPF: ospf_spf_calculate: running Dijkstra for area 0.0.0.0
2002/04/28 16:26:42 OSPF: SPF Result: 0 [R] 192.168.5.121
2002/04/28 16:26:42 OSPF: ========== OSPF routing table ==========
2002/04/28 16:26:42 OSPF: ========================================
2002/04/28 16:26:42 OSPF: ospf_process_stub():processing stubs for area 0.0.0.0
2002/04/28 16:26:42 OSPF: ospf_process_stub():processing router LSA, id: 192.168.5.121
2002/04/28 16:26:42 OSPF: ospf_process_stub(): we have 1 links to process
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): Start
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): processing route to 192.168.5.0/24
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): calculated cost is 0 + 10 = 10
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): installing new route
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): this network is on this router
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): the interface is eth0:192.168.5.121
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): Stop
2002/04/28 16:26:42 OSPF: children of V:
2002/04/28 16:26:42 OSPF: ospf_spf_calculate: Stop
2002/04/28 16:26:42 OSPF: ospf_ia_routing():start
2002/04/28 16:26:42 OSPF: ospf_ia_routing():not ABR, considering all areas
2002/04/28 16:26:42 OSPF: Pruning unreachable networks
2002/04/28 16:26:42 OSPF: Pruning unreachable routers
2002/04/28 16:26:42 OSPF: Route: Router Routing Table free
2002/04/28 16:26:42 OSPF: SPF: calculation complete
--------------------------------8<---------------------------------------
2002/04/28 16:25:53 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 16:25:57 OSPF: Packet 192.168.5.123 [Hello:RECV]: Options *|*|-|-|-|-|E|*
2002/04/28 16:26:03 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 16:26:13 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 16:26:23 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 16:26:33 OSPF: make_hello: options: 2, int: eth0:192.168.5.121
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): Start
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): looked through areas
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): bb_configured: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): bb_act_attached: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): areas_configured: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): areas_act_attached: 1
2002/04/28 16:26:37 OSPF: nsm_change_status(): scheduling new router-LSA origination
2002/04/28 16:26:37 OSPF: DR-Election[1nd]: Backup 0.0.0.0
2002/04/28 16:26:37 OSPF: DR-Election[1nd]: DR 192.168.5.121
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): Start
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): looked through areas
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): bb_configured: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): bb_act_attached: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): areas_configured: 1
2002/04/28 16:26:37 OSPF: ospf_check_abr_status(): areas_act_attached: 1
2002/04/28 16:26:37 OSPF: Timer[router-LSA]: (router-LSA Refresh expire)
2002/04/28 16:26:37 OSPF: counting fully adjacent virtual neighbors in area 0.0.0.0
2002/04/28 16:26:37 OSPF: there are 0 of them
2002/04/28 16:26:37 OSPF: SPF: calculation timer scheduled
2002/04/28 16:26:37 OSPF: SPF: calculation timer delay = 5
2002/04/28 16:26:37 OSPF: ospf_flood_through_interface(): considering int eth0:192.168.5.121
2002/04/28 16:26:37 OSPF: ospf_flood_through_interface(): considering nbr 192.168.5.121
2002/04/28 16:26:42 OSPF: SPF: Timer (SPF calculation expire)
2002/04/28 16:26:42 OSPF: ospf_spf_calculate: Start
2002/04/28 16:26:42 OSPF: ospf_spf_calculate: running Dijkstra for area 0.0.0.0
2002/04/28 16:26:42 OSPF: SPF Result: 0 [R] 192.168.5.121
2002/04/28 16:26:42 OSPF: ========== OSPF routing table ==========
2002/04/28 16:26:42 OSPF: ========================================
2002/04/28 16:26:42 OSPF: ospf_process_stub():processing stubs for area 0.0.0.0
2002/04/28 16:26:42 OSPF: ospf_process_stub():processing router LSA, id: 192.168.5.121
2002/04/28 16:26:42 OSPF: ospf_process_stub(): we have 1 links to process
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): Start
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): processing route to 192.168.5.0/24
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): calculated cost is 0 + 10 = 10
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): installing new route
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): this network is on this router
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): the interface is eth0:192.168.5.121
2002/04/28 16:26:42 OSPF: ospf_intra_add_stub(): Stop
2002/04/28 16:26:42 OSPF: children of V:
2002/04/28 16:26:42 OSPF: ospf_spf_calculate: Stop
2002/04/28 16:26:42 OSPF: ospf_ia_routing():start
2002/04/28 16:26:42 OSPF: ospf_ia_routing():not ABR, considering all areas
2002/04/28 16:26:42 OSPF: Pruning unreachable networks
2002/04/28 16:26:42 OSPF: Pruning unreachable routers
2002/04/28 16:26:42 OSPF: Route: Router Routing Table free
2002/04/28 16:26:42 OSPF: SPF: calculation complete
--------------------------------8<---------------------------------------
我们看到r1生成一个LSA包，通知其它路由器，由于网络里只有自己了，又选自己为DR。r2也是一样。 我们再
插上网线，查看ospfd.log：
--------------------------------8<---------------------------------------
2002/04/28 16:52:08 OSPF: Packet 192.168.5.123 [Hello:RECV]: Options *|*|-|-|-|-|E|*
2002/04/28 16:52:08 OSPF: NSM[eth0:192.168.5.121:0.0.0.0]: start
2002/04/28 16:52:08 OSPF: DR-Election[1st]: Backup 192.168.5.123
2002/04/28 16:52:08 OSPF: DR-Election[1st]: DR 192.168.5.121
2002/04/28 16:52:08 OSPF: DR-Election[1st]: Backup 0.0.0.0
2002/04/28 16:52:08 OSPF: DR-Election[1st]: DR 192.168.5.123
2002/04/28 16:52:08 OSPF: DR-Election[2nd]: Backup 192.168.5.121
2002/04/28 16:52:08 OSPF: DR-Election[2nd]: DR 192.168.5.123
--------------------------------8<---------------------------------------
2002/04/28 16:52:08 OSPF: Packet 192.168.5.123 [Hello:RECV]: Options *|*|-|-|-|-|E|*
2002/04/28 16:52:08 OSPF: NSM[eth0:192.168.5.121:0.0.0.0]: start
2002/04/28 16:52:08 OSPF: DR-Election[1st]: Backup 192.168.5.123
2002/04/28 16:52:08 OSPF: DR-Election[1st]: DR 192.168.5.121
2002/04/28 16:52:08 OSPF: DR-Election[1st]: Backup 0.0.0.0
2002/04/28 16:52:08 OSPF: DR-Election[1st]: DR 192.168.5.123
2002/04/28 16:52:08 OSPF: DR-Election[2nd]: Backup 192.168.5.121
2002/04/28 16:52:08 OSPF: DR-Election[2nd]: DR 192.168.5.123
--------------------------------8<---------------------------------------
由于拔了网线，r1和r2都把自己选为DR，一个网络只能有一个DR，所以恢复连接后它们重新进行了DR选 举，由
于192.168.5.123的router id大，所以它被选为DR。
保存一下配置
r1_ospfd# copy run start
Configuration saved to /usr/local/etc/ospfd.conf
r2_ospfd# copy run start
Configuration saved to /usr/local/etc/ospfd.conf
Configuration saved to /usr/local/etc/ospfd.conf
r2_ospfd# copy run start
Configuration saved to /usr/local/etc/ospfd.conf
以上只是演示了最简单的OSPF的配置，而OSPF在大型网络才广泛的使用，配置也复杂多很多。即使是 Zebra，
也还可用做复杂的多的OSPF实验。
4、用Zebra做BGP实验
RIP和OSPF都是内部网关协议（IGP），BGP属于外部网关协议（EGP）。BGP广泛用于Internet以连接 ISP，并将
企业与ISP互连。
当BGP的影响被完全了解，并且至少下列情况之一存在时，在AS中使用BGP才是最恰当的：
1 AS允许数据包穿过它到达其它自治系统（例如，某个服务提供商）。
2 AS有到其它自治系统的多条连接。
3 必须对进入和离开AS的数据流进行控制。
1 AS允许数据包穿过它到达其它自治系统（例如，某个服务提供商）。
2 AS有到其它自治系统的多条连接。
3 必须对进入和离开AS的数据流进行控制。
对于互连的自治系统来说，BGP并不总是恰当的解决方案，如果有如下情况中的一个或多个时，不要使 用BGP：
1 只有到Internet或另一AS的单一连接。
2 无需考虑路由策略或路由选择。
3 路由器缺乏经常性的BGP更新的内存或处理器。
4 对路由过滤和BGP路径选择过程的了解十分有限。
5 在自治系统间的带宽较低。
在这些情况下，应该使用静态路由。
1 只有到Internet或另一AS的单一连接。
2 无需考虑路由策略或路由选择。
3 路由器缺乏经常性的BGP更新的内存或处理器。
4 对路由过滤和BGP路径选择过程的了解十分有限。
5 在自治系统间的带宽较低。
在这些情况下，应该使用静态路由。
Zebra支持BGP-4和BGP-4+，下面实验只是演示BGP的基本命令，以及debug的一些信息。一个比较复杂 的用
Zebra做BGP实验见http://www.unixreview.com/print/documentID=15977，有条件可以做一下。
Zebra使用bgpd程序实现BGP路由功能，但bgpd需要从zebra程序获得接口信息，所以zebra程序必须在 bgpd程序
之前运行。
初始化第一台机器：
shell_1> cd /usr/local/etc
shell_1> cp zebra.conf.sample zebra.conf
shell_1> cp bgpd.conf.sample bgpd.conf
shell_1> zebra -d
shell_1> cp zebra.conf.sample zebra.conf
shell_1> cp bgpd.conf.sample bgpd.conf
shell_1> zebra -d
还有一个bgpd.conf.sample2配置样例是用于IPv6的。
进入zebra设置IP
shell_1> telnet localhost 2601
Password:
Router> en
Password:
Router# conf t
Router(config)# hostname r1
r1(config)# int eth0
r1(config-if)# ip address 192.168.5.121/24
r1(config-if)# ctrl+z
r1# copy run start
Password:
Router> en
Password:
Router# conf t
Router(config)# hostname r1
r1(config)# int eth0
r1(config-if)# ip address 192.168.5.121/24
r1(config-if)# ctrl+z
r1# copy run start
进入第一台机器的bgp设置
shell_1> bgpd -d
启动bgpd，我们看到TCP端口179已经打开。两台BGP路由器相互间建立一条TCP连接，交换消息以打开 和确认连
接参数。这两台路由器被称为对等路由器，或者邻居。
shell_1> telnet localhost 2605
Password:
bgpd> en
bgpd# conf t
bgpd(config)# hostname r1_bgpd
r1_bgpd(config)# router bgp 7675
Password:
bgpd> en
bgpd# conf t
bgpd(config)# hostname r1_bgpd
r1_bgpd(config)# router bgp 7675
配置样例里已经指定了AS为7675，我们懒的改就拿来用。AS是一个16bit的数字，其范围从1到 65535。RFC
1930给出了AS编号使用指南。从64512到65535的AS编号范围是留作私用的，类似私有IP。
r1_bgpd(config-router)# network 192.168.5.0/24
r1_bgpd(config-router)# neighbor 192.168.5.121 remote-as 7676
r1_bgpd(config-router)# neighbor 192.168.5.121 remote-as 7676
查看bgp信息：
r1_bgpd# sh ip bgp
BGP table version is 0, local router ID is 192.168.5.123
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete
BGP table version is 0, local router ID is 192.168.5.123
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 192.168.5.0 0.0.0.0 32768 i
*> 192.168.5.0 0.0.0.0 32768 i
Total number of prefixes 1
把log记录到文件：
r1_bgpd# conf t
r1_bgpd(config)# log file /usr/local/etc/bgpd.log
r1_bgpd(config)# log file /usr/local/etc/bgpd.log
打开debug选项：
r1_bgpd(config)# exit
r1_bgpd debug bgp events
r1_bgpd debug bgp keepalives
r1_bgpd debug bgp updates
r1_bgpd debug bgp events
r1_bgpd debug bgp keepalives
r1_bgpd debug bgp updates
然后在shell下用tail查看log记录：
shell_1> tail -f /usr/local/etc/bgpd.log
--------------------------------8<---------------------------------------
2002/04/29 19:13:08 BGP: 192.168.5.121 [Event] Connect start to 192.168.5.121 fd 10
2002/04/29 19:13:11 BGP: 192.168.5.121 [Event] Connect failed (Operation now in progress)
--------------------------------8<---------------------------------------
--------------------------------8<---------------------------------------
2002/04/29 19:13:08 BGP: 192.168.5.121 [Event] Connect start to 192.168.5.121 fd 10
2002/04/29 19:13:11 BGP: 192.168.5.121 [Event] Connect failed (Operation now in progress)
--------------------------------8<---------------------------------------
r1不能连接邻居192.168.5.121。
第二台机器的设置
前面的初始化和第一台一样，不过这里名字设成r2便于辨认，IP设成了192.168.5.123/24。
进入第二台机器的bgp设置
shell_2> bgpd -d
shell_2> telnet localhost 2605
Password:
bgpd> en
bgpd# conf t
bgpd(config)# hostname r2_bgpd
shell_2> telnet localhost 2605
Password:
bgpd> en
bgpd# conf t
bgpd(config)# hostname r2_bgpd
AS要设成不一样，所以修改一下：
r2_bgpd(config)# no router bgp 7675
r2_bgpd(config)# router bgp 7676
r2_bgpd(config-router)# network 192.168.5.0/24
r2_bgpd(config-router)# neighbor 192.168.5.123 remote-as 7675
r2_bgpd(config)# router bgp 7676
r2_bgpd(config-router)# network 192.168.5.0/24
r2_bgpd(config-router)# neighbor 192.168.5.123 remote-as 7675
这时第一台机器的log出现如下信息：
--------------------------------8<---------------------------------------
2002/04/29 19:16:35 BGP: [Event] BGP connection from host 192.168.5.121
2002/04/29 19:16:35 BGP: [Event] Make dummy peer structure until read Open packet
2002/04/29 19:16:35 BGP: 192.168.5.121 [Event] Transfer temporary BGP peer to existing one
2002/04/29 19:16:35 BGP: 192.168.5.121 [Event] Accepting BGP peer delete
2002/04/29 19:16:35 BGP: 192.168.5.121 send UPDATE 192.168.5.0/24 nexthop 192.168.5.123, origin
2002/04/29 19:16:35 BGP: [Event] BGP connection from host 192.168.5.121
2002/04/29 19:16:35 BGP: [Event] Make dummy peer structure until read Open packet
2002/04/29 19:16:35 BGP: 192.168.5.121 [Event] Transfer temporary BGP peer to existing one
2002/04/29 19:16:35 BGP: 192.168.5.121 [Event] Accepting BGP peer delete
2002/04/29 19:16:35 BGP: 192.168.5.121 send UPDATE 192.168.5.0/24 nexthop 192.168.5.123, origin
i, path
2002/04/29 19:16:35 BGP: 192.168.5.121 rcvd UPDATE w/ attr: nexthop 192.168.5.121, origin i, path
2002/04/29 19:16:35 BGP: 192.168.5.121 rcvd UPDATE w/ attr: nexthop 192.168.5.121, origin i, path
7676
2002/04/29 19:16:35 BGP: 192.168.5.121 rcvd 192.168.5.0/24
--------------------------------8<---------------------------------------
2002/04/29 19:16:35 BGP: 192.168.5.121 rcvd 192.168.5.0/24
--------------------------------8<---------------------------------------
两台bgp已经互连了。再看一下第一台机器的bgp信息：
r1_bgpd# sh ip bgp
BGP table version is 0, local router ID is 192.168.5.123
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete
BGP table version is 0, local router ID is 192.168.5.123
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* 192.168.5.0 192.168.5.121 0 7676 i
*> 0.0.0.0 32768 i
* 192.168.5.0 192.168.5.121 0 7676 i
*> 0.0.0.0 32768 i
Total number of prefixes 1
r1_bgpd# sh ip bgp neighbors
BGP neighbor is 192.168.5.121, remote AS 7676, local AS 7675, external link
BGP version 4, remote router ID 192.168.5.121
BGP state = Established, up for 00:01:13
Last read 00:00:13, hold time is 180, keepalive interval is 60 seconds
Neighbor capabilities:
Route refresh: advertised and received (old and new)
Address family IPv4 Unicast: advertised and received
Received 98 messages, 0 notifications, 0 in queue
Sent 103 messages, 0 notifications, 0 in queue
Route refresh request: received 0, sent 0
Minimum time between advertisement runs is 0 seconds
BGP neighbor is 192.168.5.121, remote AS 7676, local AS 7675, external link
BGP version 4, remote router ID 192.168.5.121
BGP state = Established, up for 00:01:13
Last read 00:00:13, hold time is 180, keepalive interval is 60 seconds
Neighbor capabilities:
Route refresh: advertised and received (old and new)
Address family IPv4 Unicast: advertised and received
Received 98 messages, 0 notifications, 0 in queue
Sent 103 messages, 0 notifications, 0 in queue
Route refresh request: received 0, sent 0
Minimum time between advertisement runs is 0 seconds
For address family: IPv4 Unicast
Community attribute sent to this neighbor (both)
1 accepted prefixes
Community attribute sent to this neighbor (both)
1 accepted prefixes
Connections established 2; dropped 1
Local host: 192.168.5.123, Local port: 179
Foreign host: 192.168.5.121, Foreign port: 1029
Nexthop: 192.168.5.123
Read thread: on Write thread: off
Local host: 192.168.5.123, Local port: 179
Foreign host: 192.168.5.121, Foreign port: 1029
Nexthop: 192.168.5.123
Read thread: on Write thread: off
Zebra还支持很多BGP的特性，请参考GNU Zebra Manual，有条件的可以做一下那些实验。
Zebra的Mailing List比较活跃，有许多人在那里讨论Zebra的开发和配置等等，有问题的话，在那里应该 能得
到解答。
Reference
GNU Zebra Manual
http://www.pointless.net/~jasper/zebra-html/zebra_toc.html#SEC_Contents
组建可扩展的Cisco网络
http://www.unixreview.com/print/documentID=15977]
http://www.pointless.net/~jasper/zebra-html/zebra_toc.html#SEC_Contents
组建可扩展的Cisco网络
http://www.unixreview.com/print/documentID=15977]
本文转自 曾永刚 51CTO博客，原文链接:http://blog.51cto.com/zyg0227/331405