bgp防环实验解决路由黑洞问题

bgp防环实验解决路由黑洞问题

解决路由黑洞方法如下：

由于路由在传递的过程中，AR2和AR4建立了bgp邻居，但是和AR3没建立bgp，所以导致AR3上学习不到去200.1.1.1的对应路由，AR3查不到对应路由就丢弃了，所以产生了路由黑洞，导致100.1.1.1去ping200.1.1.1不通。

解决路由黑洞方法有：

1.全互联

2.路由引入：将bgp路由引入igp（但是bgp路由几十万条，igp承载不了这么大的路由，会导致设备炸了，所以不推荐）

3.mpls多协议标签交换（推荐）。

配置如下：

AR1配置：

[AR1]dis cu
#
sysname AR1
#
interface GigabitEthernet0/0/0
ip address 12.1.1.1 255.255.255.0
#
interface LoopBack0
ip address 100.1.1.1 255.255.255.255
#
bgp 1
router-id 1.1.1.1
peer 12.1.1.2 as-number 234
#
ipv4-family unicast
undo synchronization
network 100.1.1.1 255.255.255.255
peer 12.1.1.2 enable

AR2配置如下：

[AR2]dis cu
sysname AR2
#
interface GigabitEthernet0/0/0
ip address 12.1.1.2 255.255.255.0
#
interface GigabitEthernet0/0/1
ip address 23.1.1.2 255.255.255.0
#
interface LoopBack0
ip address 2.2.2.2 255.255.255.255
#
bgp 234
router-id 2.2.2.2
peer 3.3.3.3 as-number 234
peer 3.3.3.3 connect-interface LoopBack0
peer 4.4.4.4 as-number 234
peer 4.4.4.4 connect-interface LoopBack0
peer 12.1.1.1 as-number 1
#
ipv4-family unicast
undo synchronization
peer 3.3.3.3 enable
peer 3.3.3.3 next-hop-local
peer 4.4.4.4 enable
peer 4.4.4.4 next-hop-local
peer 12.1.1.1 enable
#
ospf 1 router-id 2.2.2.2
area 0.0.0.0
network 2.2.2.2 0.0.0.0
network 23.1.1.2 0.0.0.0

AR3配置如下：

[AR3]DIS CU
#
sysname AR3
#
interface GigabitEthernet0/0/0
ip address 34.1.1.3 255.255.255.0
#
interface GigabitEthernet0/0/1
ip address 23.1.1.3 255.255.255.0
#
interface LoopBack0
ip address 3.3.3.3 255.255.255.255
#
bgp 234
peer 2.2.2.2 as-number 234
peer 2.2.2.2 connect-interface LoopBack0
peer 4.4.4.4 as-number 234
peer 4.4.4.4 connect-interface LoopBack0
#
ipv4-family unicast
undo synchronization
peer 2.2.2.2 enable
peer 4.4.4.4 enable
#
ospf 1 router-id 3.3.3.3
area 0.0.0.0
network 3.3.3.3 0.0.0.0
network 23.1.1.3 0.0.0.0
network 34.1.1.3 0.0.0.0

AR4配置如下：

[AR4]dis cu
#
sysname AR4
#
interface GigabitEthernet0/0/0
ip address 45.1.1.4 255.255.255.0
#
interface GigabitEthernet0/0/1
ip address 34.1.1.4 255.255.255.0
#
interface LoopBack0
ip address 4.4.4.4 255.255.255.255
#
bgp 234
router-id 4.4.4.4
peer 2.2.2.2 as-number 234
peer 2.2.2.2 connect-interface LoopBack0
peer 3.3.3.3 as-number 234
peer 3.3.3.3 connect-interface LoopBack0
peer 45.1.1.5 as-number 5
peer 45.1.1.5 ebgp-max-hop 255
#
ipv4-family unicast
undo synchronization
peer 2.2.2.2 enable
peer 2.2.2.2 next-hop-local
peer 3.3.3.3 enable
peer 3.3.3.3 next-hop-local
peer 45.1.1.5 enable
#
ospf 1 router-id 4.4.4.4
area 0.0.0.0
network 4.4.4.4 0.0.0.0
network 34.1.1.4 0.0.0.0

AR5配置如下：

[AR5]dis cu
#
sysname AR5
#
interface GigabitEthernet0/0/0
ip address 45.1.1.5 255.255.255.0
#
interface LoopBack0
ip address 200.1.1.1 255.255.255.255
#
bgp 5
peer 45.1.1.4 as-number 234
#
ipv4-family unicast
undo synchronization
network 200.1.1.1 255.255.255.255
peer 45.1.1.4 enable

验证现象：