问题: AB去R1走R3 ,R4备份 CD 去R1走R4,R3备份 A去C走R3,R4备份 B去D走R4,R3不能提供备份 来回路径一致
解决方法 1、 EIGRP选路主要受延时和带宽的影响,通过修改延时解决AB访问公网R1的选路,CD同理 R4 interface Serial0/1 delay 2001
R5 interface Serial0/1 delay 2001 2、 通过偏移列表影响AB互访的路径(来去路径都要做) R5 router eigrp 90 offset-list 1 in 10 Serial0/1
access-list 1 permit 172.16.69.0 0.0.0.255
R6 router eigrp 90 offset-list 1 in 10 Serial0/1
access-list 1 permit 172.16.57.0 0.0.0.255
3、 通过分发列表阻止BD通过R3 R5 router eigrp 90 distribute-list 2 in Serial0/0
access-list 2 deny 172.16.60.0 0.0.0.255 access-list 2 permit any R6 router eigrp 90 distribute-list 2 in Serial0/0
access-list 2 deny 172.16.58.0 0.0.0.255
access-list 2 permit any 4、 由于本实验需要访问公网,存在访问公网的的默认路由,故只有分发列表无法阻止,可以通过静态放空通过R3的备份(注意:由于EIGRP支持宣告静态,故R5和R6需要做EIGRP的精确宣告) R5 ip route 172.16.60.0 255.255.255.0 Null0 100 R6 ip route 172.16.58.0 255.255.255.0 Null0 100
详细配置命令
R1 interface Loopback0 ip address 1.1.1.1 255.255.255.0
interface Serial0/0 ip address 12.1.1.1 255.255.255.0
R2 interface Loopback0 ip address 172.16.2.2 255.255.255.0
interface Serial0/0 ip address 12.1.1.2 255.255.255.0 ip nat outside
interface Serial0/1 ip address 172.16.23.1 255.255.255.0 ip nat inside
interface Serial0/2 ip address 172.16.24.1 255.255.255.0 ip nat inside
inrouter eigrp 90 network 172.16.0.0 redistribute static metric 1544 100 255 1 1500
ip nat inside source list 1 interface Serial0/0 overload ip route 0.0.0.0 0.0.0.0 Serial0/0
access-list 1 permit 172.16.0.0 0.0.255.255
R3 interface Loopback0 ip address 172.16.3.3 255.255.255.0
interface Serial0/0 ip address 172.16.23.2 255.255.255.0
interface Serial0/1 ip address 172.16.35.1 255.255.255.0
interface Serial0/2 ip address 172.16.36.1 255.255.255.0 delay 2001
router eigrp 90 network 172.16.0.0
R4 interface Loopback0 ip address 172.16.4.4 255.255.255.0
interface Serial0/0 ip address 172.16.24.2 255.255.255.0
interface Serial0/1 ip address 172.16.45.1 255.255.255.0 delay 2001
interface Serial0/2 ip address 172.16.46.1 255.255.255.0 serial restart-delay 0
router eigrp 90 network 172.16.0.0
R5 interface Loopback0 ip address 172.16.5.5 255.255.255.0
interface Serial0/0 ip address 172.16.35.2 255.255.255.0
interface Serial0/1 ip address 172.16.45.2 255.255.255.0 delay 2001
interface Serial0/2 ip address 172.16.57.1 255.255.255.0
interface Serial0/3 ip address 172.16.58.1 255.255.255.0
router eigrp 90 distribute-list 2 in Serial0/0 network 172.16.35.0 0.0.0.255 network 172.16.45.0 0.0.0.255 network 172.16.57.0 0.0.0.255 network 172.16.58.0 0.0.0.255 offset-list 1 in 10 Serial0/1
ip route 172.16.60.0 255.255.255.0 Null0 100
access-list 1 permit 172.16.69.0 0.0.0.255 access-list 2 deny 172.16.60.0 0.0.0.255 access-list 2 permit any
R6 interface Loopback0 ip address 172.16.6.6 255.255.255.0
interface Serial0/0 ip address 172.16.36.2 255.255.255.0 delay 2001
interface Serial0/1 ip address 172.16.46.2 255.255.255.0
interface Serial0/2 ip address 172.16.69.1 255.255.255.0
interface Serial0/3 ip address 172.16.60.1 255.255.255.0
router eigrp 90 distribute-list 2 in Serial0/0 network 172.16.36.0 0.0.0.255 network 172.16.46.0 0.0.0.255 network 172.16.60.0 0.0.0.255 network 172.16.69.0 0.0.0.255 offset-list 1 in 10 Serial0/1
ip route 172.16.58.0 255.255.255.0 Null0 100
access-list 1 permit 172.16.57.0 0.0.0.255 access-list 2 deny 172.16.58.0 0.0.0.255 access-list 2 permit any