配置LDP跨域扩展示例
介绍LDP跨域扩展的配置过程,包括配置全局使能MPLS和MPLS LDP以及配置聚合路由的策略。
组网需求
如图4-11所示,存在Area 10和Area 20两个IGP域。需要建立LSRA到LSRB以及LSRA到LSRC的跨越两个IGP域的LSP。要求在LSRA上配置LDP跨域扩展功能,使LSRA查找最长匹配路由建立LSP。
配置思路
采用如下的思路实现LDP跨域扩展:
配置各节点接口的IP地址及作为LSR ID的Loopback地址。
配置IS-IS协议的基本功能。
配置聚合路由的策略。
使能各节点全局和接口的MPLS和MPLS LDP。
配置LDP跨域扩展。
操作步骤
- 配置各节点接口的IP地址及作为LSR ID的Loopback地址
按照图4-11配置各接口IP地址和掩码,包括Loopback接口,具体配置过程略。
- 配置IS-IS协议的基本功能
# 配置LSRA。
<~LSRA> system-view
[~LSRA] isis 1
[*LSRA-isis-1] is-level level-2
[*LSRA-isis-1] network-entity 20.0010.0100.0001.00
[*LSRA-isis-1] quit
[*LSRA] interface gigabitethernet 0/1/0
[*LSRA-Gigabitethernet0/1/0] isis enable 1
[*LSRA-Gigabitethernet0/1/0] quit
[*LSRA] interface loopback 0
[*LSRA-LoopBack0] isis enable 1
[*LSRA-LoopBack0] commit
[~LSRA-LoopBack0] quit
# 配置LSRD。
<~LSRD> system-view
[~LSRD] isis 1
[*LSRD-isis-1] network-entity 10.0010.0200.0001.00
[*LSRD-isis-1] quit
[*LSRD] interface gigabitethernet 0/1/0
[*LSRD-Gigabitethernet0/1/0] isis enable 1
[*LSRD-Gigabitethernet0/1/0] isis circuit-level level-2
[*LSRD-Gigabitethernet0/1/0] quit
[*LSRD] interface gigabitethernet 0/1/1
[*LSRD-Gigabitethernet0/1/1] isis enable 1
[*LSRD-Gigabitethernet0/1/1] isis circuit-level level-1
[*LSRD-Gigabitethernet0/1/1] quit
[*LSRD] interface gigabitethernet 0/1/2
[*LSRD-Gigabitethernet0/1/2] isis enable 1
[*LSRD-Gigabitethernet0/1/2] isis circuit-level level-1
[*LSRD-Gigabitethernet0/1/2] quit
[*LSRD] interface loopback 0
[*LSRD-LoopBack0] isis enable 1
[*LSRD-LoopBack0] commit
[~LSRD-LoopBack0] quit
# 配置LSRB。
<~LSRB> system-view
[~LSRB] isis 1
[*LSRB-isis-1] is-level level-1
[*LSRB-isis-1] network-entity 10.0010.0300.0001.00
[*LSRB-isis-1] quit
[*LSRB] interface gigabitethernet 0/1/0
[*LSRB-Gigabitethernet0/1/0] isis enable 1
[*LSRB-Gigabitethernet0/1/0] quit
[*LSRB] interface loopback 0
[*LSRB-LoopBack0] isis enable 1
[*LSRB-LoopBack0] commit
[~LSRB-LoopBack0] quit
# 配置LSRC。
<~LSRC> system-view
[~LSRC] isis 1
[*LSRC-isis-1] is-level level-1
[*LSRC-isis-1] network-entity 10.0010.0300.0002.00
[*LSRC-isis-1] quit
[*LSRC] interface gigabitethernet 0/1/0
[*LSRC-Gigabitethernet0/1/0] isis enable 1
[*LSRC-Gigabitethernet0/1/0] quit
[*LSRC] interface loopback 0
[*LSRC-LoopBack0] isis enable 1
[*LSRC-LoopBack0] commit
[~LSRC-LoopBack0] quit
# 在LSRA上执行display ip routing-table命令查看路由信息。
[~LSRA] display ip routing-table
Route Flags: R - relay, D - download to fib, T - to vpn-instance, B - black hole route ------------------------------------------------------------------------------ Routing Tables: Public Destinations : 11 Routes : 11 Destination/Mask Proto Pre Cost Flags NextHop Interface 1.1.1.1/32 Direct 0 0 D 127.0.0.1 LoopBack0 2.2.2.2/32 ISIS-L1 15 10 D 10.1.1.2 Gigabitethernet0/1/0 1.3.0.1/32 ISIS-L1 15 20 D 10.1.1.2 Gigabitethernet0/1/0 1.3.0.2/32 ISIS-L1 15 20 D 10.1.1.2 Gigabitethernet0/1/0 10.1.1.0/24 Direct 0 0 D 10.1.1.1 Gigabitethernet0/1/0 10.1.1.1/32 Direct 0 0 D 127.0.0.1 Gigabitethernet0/1/0 10.1.1.2/32 Direct 0 0 D 10.1.1.2 Gigabitethernet10/0/0 20.1.1.0/24 ISIS-L1 15 20 D 10.1.1.2 Gigabitethernet0/1/0 20.1.2.0/24 ISIS-L1 15 20 D 10.1.1.2 Gigabitethernet0/1/0 127.0.0.0/8 Direct 0 0 D 127.0.0.1 InLoopBack0 127.0.0.1/32 Direct 0 0 D 127.0.0.1 InLoopBack0
- 配置聚合路由的策略
# 在LSRD上执行summary命令将到LSRB和LSRC的主机路由聚合。
[~LSRD] isis 1
[*LSRD-isis-1] summary 1.3.0.0 255.255.255.0 avoid-feedback
[*LSRD-isis-1] commit
[~LSRD-isis-1] quit
# 在LSRA上执行display ip routing-table命令查看路由信息。
Route Flags: R - relay, D - download to fib, T - to vpn-instance, B - black hole route ------------------------------------------------------------------------------ Routing Tables: Public Destinations : 10 Routes : 10 Destination/Mask Proto Pre Cost Flags NextHop Interface 1.1.1.1/32 Direct 0 0 D 127.0.0.1 LoopBack0 2.2.2.2/32 ISIS-L1 15 10 D 10.1.1.2 Gigabitethernet0/1/0 1.3.0.0/24 ISIS-L1 15 20 D 10.1.1.2 Gigabitethernet0/1/0 10.1.1.0/24 Direct 0 0 D 10.1.1.1 Gigabitethernet0/1/0 10.1.1.1/32 Direct 0 0 D 127.0.0.1 Gigabitethernet0/1/0 10.1.1.2/32 Direct 0 0 D 10.1.1.2 Gigabitethernet0/1/0 20.1.1.0/24 ISIS-L1 15 20 D 10.1.1.2 Gigabitethernet0/1/0 20.1.2.0/24 ISIS-L1 15 20 D 10.1.1.2 Gigabitethernet0/1/0 127.0.0.0/8 Direct 0 0 D 127.0.0.1 InLoopBack0 127.0.0.1/32 Direct 0 0 D 127.0.0.1 InLoopBack0
从显示信息可以看到,到LSRB和LSRC的主机路由已经聚合。
- 配置各节点全局和接口的MPLS和MPLS LDP能力,使网络能够转发MPLS流量,并查看LSP建立情况
# 配置LSRA。
[~LSRA] mpls lsr-id 1.1.1.1
[~LSRA] mpls
[*LSRA-mpls] quit
[*LSRA] mpls ldp
[*LSRA-mpls-ldp] quit
[*LSRA] interface gigabitethernet 0/1/0
[*LSRA-Gigabitethernet0/1/0] mpls
[*LSRA-Gigabitethernet0/1/0] mpls ldp
[*LSRA-Gigabitethernet0/1/0] commit
[~LSRA-Gigabitethernet0/1/0] quit
# 配置LSRD。
[~LSRD] mpls lsr-id 2.2.2.2
[~LSRD] mpls
[*LSRD-mpls] quit
[*LSRD] mpls ldp
[*LSRD-mpls-ldp] quit
[*LSRD] interface gigabitethernet 0/1/0
[*LSRD-Gigabitethernet0/1/0] mpls
[*LSRD-Gigabitethernet0/1/0] mpls ldp
[*LSRD-Gigabitethernet0/1/0] quit
[*LSRD] interface gigabitethernet 0/1/1
[*LSRD-Gigabitethernet0/1/1] mpls
[*LSRD-Gigabitethernet0/1/1] mpls ldp
[*LSRD-Gigabitethernet0/1/1] quit
[*LSRD] interface gigabitethernet 0/1/2
[*LSRD-Gigabitethernet0/1/2] mpls
[*LSRD-Gigabitethernet0/1/2] mpls ldp
[*LSRD-Gigabitethernet0/1/2] commit
[~LSRD-Gigabitethernet0/1/2] quit
# 配置LSRB。
[~LSRB] mpls lsr-id 1.3.0.1
[~LSRB] mpls
[*LSRB-mpls] quit
[*LSRB] mpls ldp
[*LSRB-mpls-ldp] quit
[*LSRB] interface gigabitethernet 0/1/0
[*LSRB-Gigabitethernet0/1/0] mpls
[*LSRB-Gigabitethernet0/1/0] mpls ldp
[*LSRB-Gigabitethernet0/1/0] commit
[~LSRB-Gigabitethernet0/1/0] quit
# 配置LSRC。
[~LSRC] mpls lsr-id 1.3.0.2
[~LSRC] mpls
[*LSRC-mpls] quit
[*LSRC] mpls ldp
[*LSRC-mpls-ldp] quit
[*LSRC] interface gigabitethernet 0/1/0
[*LSRC-Gigabitethernet0/1/0] mpls
[*LSRC-Gigabitethernet0/1/0] mpls ldp
[*LSRC-Gigabitethernet0/1/0] commit
[~LSRC-Gigabitethernet0/1/0] quit
# 配置完成后,在LSRA上执行display mpls lsp命令,查看已经建立的LSP。
[~LSRA] display mpls lsp
------------------------------------------------------------------------------- LSP Information: LDP LSP ------------------------------------------------------------------------------- FEC In/Out Label In/Out IF Vrf Name 2.2.2.2/32 NULL/3 -/Gigabitethernet0/1/0 2.2.2.2/32 1024/3 -/Gigabitethernet0/1/0
从显示信息可以看到,缺省情况下,LDP没有建立从LSRA到LSRB和LSRC的跨域LSP。
- 配置LDP跨域扩展
# 在LSRA上执行longest-match命令,使能LDP按照最长匹配方式查找路由建立LSP。
[~LSRA] mpls ldp
[*LSRA-mpls-ldp] longest-match
[*LSRA-mpls-ldp] commit
[~LSRA-mpls-ldp] quit
- 检查配置结果
# 上述配置完成后,在LSRA上执行display mpls lsp命令,查看已经建立的LSP。
[~LSRA] display mpls lsp
------------------------------------------------------------------------------- LSP Information: LDP LSP ------------------------------------------------------------------------------- FEC In/Out Label In/Out IF Vrf Name 2.2.2.2/32 NULL/3 -/Gigabitethernet0/1/0 2.2.2.2/32 1024/3 -/Gigabitethernet0/1/0 1.3.0.1/32 NULL/1025 -/Gigabitethernet0/1/0 1.3.0.1/32 1025/1025 -/Gigabitethernet0/1/0 1.3.0.2/32 NULL/1026 -/Gigabitethernet0/1/0 1.3.0.2/32 1026/1026 -/Gigabitethernet0/1/0
从显示信息可以看到,LDP建立了从LSRA到LSRB和LSRC的跨越两个IGP域的LSP。
配置文件
LSRA的配置文件
# sysname LSRA # mpls lsr-id 1.1.1.1 mpls # mpls ldp longest-match # isis 1 is-level level-2 network-entity 20.0010.0100.0001.00 # interface gigabitethernet0/1/0 undo shutdown ip address 10.1.1.1 255.255.255.0 isis enable 1 mpls mpls ldp # interface LoopBack0 ip address 1.1.1.1 255.255.255.255 isis enable 1 # return
LSRD的配置文件
# sysname LSRD # mpls lsr-id 2.2.2.2 mpls # mpls ldp # isis 1 network-entity 10.0010.0200.0001.00 import-route isis level-1 into level-2 filter-policy ip-prefix permit-host summary 1.3.0.0 255.255.255.0 avoid-feedback # interface gigabitethernet0/1/0 undo shutdown ip address 10.1.1.2 255.255.255.0 isis enable 1 isis circuit-level level-2 mpls mpls ldp # interface gigabitethernet0/1/1 undo shutdown ip address 10.1.2.1 255.255.255.0 isis enable 1 isis circuit-level level-1 mpls mpls ldp # interface gigabitethernet0/1/2 undo shutdown ip address 10.1.3.1 255.255.255.0 isis enable 1 isis circuit-level level-1 mpls mpls ldp # interface LoopBack0 ip address 2.2.2.2 255.255.255.255 isis enable 1 # ip ip-prefix permit-host index 10 permit 0.0.0.0 32 # return
LSRB的配置文件
# sysname LSRB # mpls lsr-id 1.3.0.1 mpls # mpls ldp # isis 1 is-level level-1 network-entity 10.0010.0300.0001.00 # interface gigabitethernet0/1/0 undo shutdown ip address 10.1.2.2 255.255.255.0 isis enable 1 mpls mpls ldp # interface LoopBack0 ip address 1.3.0.1 255.255.255.255 isis enable 1 # return
LSRC的配置文件
# sysname LSRC # mpls lsr-id 1.3.0.2 mpls # mpls ldp # isis 1 is-level level-1 network-entity 10.0010.0300.0002.00 # interface gigabitethernet0/1/0 undo shutdown ip address 10.1.3.2 255.255.255.0 isis enable 1 mpls mpls ldp # interface LoopBack0 ip address 1.3.0.2 255.255.255.255 isis enable 1 # return