MPLS LDP 基本配置.doc

Service Professional Outstanding Teamwork ObtainMPLS LDP基本配置实验V0.12012-6-25Author顾赟TELPHONEOrganizationLastUpdate2013-6-22目录1实验目的32拓扑与需求32.1网络拓扑及地址规划32.2需求概述33配置与实现43.1实验步骤43.2配置MPLS43.3 结果测试53.3.1查看LDP邻居53.3.2查看LDP接口63.3.3查看LIB63.3.4查看LFIB93.3.5查看跟踪路由93.4 手工指定LDP RID103.5 修改LDP Transport-Address113.6 修改LDP Hello Time123.7 修改LDP Hold Time131 实验目的1、理解MPLS LDP的基本原理及运作机制。2 拓扑与需求2.1 网络拓扑及地址规划设备名称IP地址接口备注R112.1.1.1/24F0/01.1.1.1/32Lo0R212.1.1.2/24F0/023.1.1.2/24F1/02.2.2.2/32Lo0R323.1.1.3/24F1/03.3.3.3/32Lo02.2 需求概述1、全网配置静态路由，再配置MPLS协议，并查看其结果。2、手工指定LDP RID、修改LDP Transport-Address、修改LDP Hello time、修改LDP Hold time，并查看其结果。3 配置与实现3.1 实验步骤1、搭建拓扑，配置IP。2、配置静态路由，保证全网畅通。3、启用MPLS LDP协议。4、手工指定LDP RID。5、修改LDP Transport-Address。6、修改LDP Hello time。7、修改LDP Hold time。3.2 配置MPLSR1(config)#mpls label protocol ldp/将MPLS标签协议设为LDP，默认为LDPR1(config)#mpls label range 100 199/指定本地分配标签的范围R1(config)#interface f0/0R1(config-if)#mpls ip/指定MPLS协议，默认是LDPR2(config)#mpls label range 200 299R2(config)#interface f0/0R2(config-if)#mpls ipR2(config)#interface f1/0R2(config-if)#mpls ipR3(config)#mpls label range 300 399R3(config)#interface f1/0R3(config-if)#mpls ip首先必须在全局下启用CEF，然后才能够在接口下启MPLS LDP。标签值有20个比特位，所以除了被保留的标签值0到15以外，标签值16到1048575都可以用来进行普通报文转发。在Cisco的IOS中，默认的范围是16到100000，可以通过mpls label range命令来修改标签范围。3.3 结果测试3.3.1 查看LDP邻居R1# show mpls ldp neighbor Peer LDP Ident: 2.2.2.2:0; Local LDP Ident 1.1.1.1:0/本地LDP ID（RID + 标签空间） TCP connection: 2.2.2.2.25590 - 1.1.1.1.646 State: Oper; Msgs sent/rcvd: 12/12; Downstream Up time: 00:03:43 LDP discovery sources: FastEthernet0/0, Src IP addr: 12.1.1.2 Addresses bound to peer LDP Ident: 12.1.1.2 2.2.2.2 23.1.1.2R2#show mpls ldp neighbor Peer LDP Ident: 1.1.1.1:0; Local LDP Ident 2.2.2.2:0 TCP connection: 1.1.1.1.646 - 2.2.2.2.25590 State: Oper; Msgs sent/rcvd: 14/14; Downstream Up time: 00:05:49 LDP discovery sources: FastEthernet0/0, Src IP addr: 12.1.1.1 Addresses bound to peer LDP Ident: 12.1.1.1 1.1.1.1 Peer LDP Ident: 3.3.3.3:0; Local LDP Ident 2.2.2.2:0 TCP connection: 3.3.3.3.44602 - 2.2.2.2.646 State: Oper; Msgs sent/rcvd: 13/13; Downstream Up time: 00:04:34 LDP discovery sources: FastEthernet1/0, Src IP addr: 23.1.1.3 Addresses bound to peer LDP Ident: 23.1.1.3 3.3.3.3R3#show mpls ldp neighbor Peer LDP Ident: 2.2.2.2:0; Local LDP Ident 3.3.3.3:0 TCP connection: 2.2.2.2.646 - 3.3.3.3.44602 State: Oper; Msgs sent/rcvd: 13/13; Downstream Up time: 00:05:01 LDP discovery sources: FastEthernet1/0, Src IP addr: 23.1.1.2 Addresses bound to peer LDP Ident: 12.1.1.2 2.2.2.2 23.1.1.2LDP通过Hello消息（UDP端口646）发现对方，然后通过建立一个TCP会话（TCP端口646）在对等体之间通告标签映射信息。3.3.2 查看LDP接口R1#show mpls interfaces/查看哪些接口运行了LDPInterface IP Tunnel OperationalFastEthernet0/0 Yes (ldp) No YesR2#show mpls interfacesInterface IP Tunnel OperationalFastEthernet0/0 Yes (ldp) No YesFastEthernet1/0 Yes (ldp) No YesR3#show mpls interfaces Interface IP Tunnel OperationalFastEthernet1/0 Yes (ldp) No Yes3.3.3 查看LIBR1#show mpls ldp bindings tib entry: 1.1.1.1/32, rev 2 local binding: tag: imp-null /隐式空标签，用于倒数第二跳弹出（PHP） remote binding: tsr: 2.2.2.2:0, tag: 200 tib entry: 2.2.2.2/32, rev 4 local binding: tag: 100 remote binding: tsr: 2.2.2.2:0, tag: imp-null tib entry: 3.3.3.3/32, rev 6 local binding: tag: 101 remote binding: tsr: 2.2.2.2:0, tag: 201 tib entry: 12.1.1.0/24, rev 10 local binding: tag: imp-null remote binding: tsr: 2.2.2.2:0, tag: imp-null tib entry: 23.1.1.0/24, rev 8 local binding: tag: 102 remote binding: tsr: 2.2.2.2:0, tag: imp-nullR2#show mpls ldp bindings tib entry: 1.1.1.1/32, rev 8 local binding: tag: 200 remote binding: tsr: 1.1.1.1:0, tag: imp-null remote binding: tsr: 3.3.3.3:0, tag: 300 tib entry: 2.2.2.2/32, rev 4 local binding: tag: imp-null remote binding: tsr: 1.1.1.1:0, tag: 100 remote binding: tsr: 3.3.3.3:0, tag: 301 tib entry: 3.3.3.3/32, rev 10 local binding: tag: 201 remote binding: tsr: 1.1.1.1:0, tag: 101 remote binding: tsr: 3.3.3.3:0, tag: imp-null tib entry: 12.1.1.0/24, rev 6 local binding: tag: imp-null remote binding: tsr: 1.1.1.1:0, tag: imp-null remote binding: tsr: 3.3.3.3:0, tag: 302 tib entry: 23.1.1.0/24, rev 5 local binding: tag: imp-null remote binding: tsr: 1.1.1.1:0, tag: 102 remote binding: tsr: 3.3.3.3:0, tag: imp-null R3#show mpls ldp bindings tib entry: 1.1.1.1/32, rev 2 local binding: tag: 300 remote binding: tsr: 2.2.2.2:0, tag: 200 tib entry: 2.2.2.2/32, rev 4 local binding: tag: 301 remote binding: tsr: 2.2.2.2:0, tag: imp-null tib entry: 3.3.3.3/32, rev 6 local binding: tag: imp-null remote binding: tsr: 2.2.2.2:0, tag: 201 tib entry: 12.1.1.0/24, rev 10 local binding: tag: 302 remote binding: tsr: 2.2.2.2:0, tag: imp-null tib entry: 23.1.1.0/24, rev 8 local binding: tag: imp-null remote binding: tsr: 2.2.2.2:0, tag: imp-nullR1#show mpls ip binding /另一条查看LIB命令 1.1.1.1/32 in label: imp-null /本地捆绑的标签 out label: 200 lsr: 2.2.2.2:0 /远程捆绑的标签 2.2.2.2/32 in label: 100 out label: imp-null lsr: 2.2.2.2:0 inuse/正被LFIB所使用的标签 3.3.3.3/32 in label: 101 out label: 201 lsr: 2.2.2.2:0 inuse 12.1.1.0/24 in label: imp-null out label: imp-null lsr: 2.2.2.2:0 23.1.1.0/24 in label: 102 out label: imp-null lsr: 2.2.2.2:0 inuseR2#show mpls ip binding 1.1.1.1/32 in label: 200 out label: imp-null lsr: 1.1.1.1:0 inuse out label: 300 lsr: 3.3.3.3:0 2.2.2.2/32 in label: imp-null out label: 100 lsr: 1.1.1.1:0 out label: 301 lsr: 3.3.3.3:0 3.3.3.3/32 in label: 201 out label: 101 lsr: 1.1.1.1:0 out label: imp-null lsr: 3.3.3.3:0 inuse 12.1.1.0/24 in label: imp-null out label: imp-null lsr: 1.1.1.1:0 out label: 302 lsr: 3.3.3.3:0 23.1.1.0/24 in label: imp-null out label: 102 lsr: 1.1.1.1:0 out label: imp-null lsr: 3.3.3.3:0R3#show mpls ip binding 1.1.1.1/32 in label: 300 out label: 200 lsr: 2.2.2.2:0 inuse 2.2.2.2/32 in label: 301 out label: imp-null lsr: 2.2.2.2:0 inuse 3.3.3.3/32 in label: imp-null out label: 201 lsr: 2.2.2.2:0 12.1.1.0/24 in label: 302 out label: imp-null lsr: 2.2.2.2:0 inuse 23.1.1.0/24 in label: imp-null out label: imp-null lsr: 2.2.2.2:0 3.3.4 查看LFIBR1#show mpls forwarding-tableLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface100 Pop tag 2.2.2.2/32 0 Fa0/0 12.1.1.2101 201 3.3.3.3/32 0 Fa0/0 12.1.1.2102 Pop tag 23.1.1.0/24 0 Fa0/0 12.1.1.2R2#show mpls forwarding-tableLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface200 Pop tag 1.1.1.1/32 0 Fa0/0 12.1.1.1201 Pop tag 3.3.3.3/32 570 Fa1/0 23.1.1.3R3#show mpls forwarding-table Local Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface300 200 1.1.1.1/32 0 Fa1/0 23.1.1.2301 Pop tag 2.2.2.2/32 0 Fa1/0 23.1.1.2302 Pop tag 12.1.1.0/24 0 Fa1/0 23.1.1.23.3.5 查看跟踪路由R1#traceroute 3.3.3.3 source 1.1.1.1Type escape sequence to abort.Tracing the route to 3.3.3.3 1 12.1.1.2 MPLS: Label 201 Exp 0 84 msec 64 msec 56 msec 2 23.1.1.3 100 msec * 64 msecR3#traceroute 1.1.1.1 source 3.3.3.3Type escape sequence to abort.Tracing the route to 1.1.1.1 1 23.1.1.2 MPLS: Label 200 Exp 0 48 msec 64 msec 64 msec 2 12.1.1.1 60 msec * 68 msec3.4 手工指定LDP RIDR3(config)#mpls ldp router-id f1/0 force /强制指定LDP RIDR3(config)#*Mar 1 02:07:59.307: %TDP-5-INFO: Default-IP-Routing-Table: TDP ID removed*Mar 1 02:07:59.311: %LDP-5-NBRCHG: LDP Neighbor 2.2.2.2:0 (1) is DOWN (LDP Router ID changed)R3(config)#*Mar 1 02:08:04.423: %LDP-5-NBRCHG: LDP Neighbor 2.2.2.2:0 (1) is UPR3#show mpls ldp discovery detail /显示所有的MPLS-enabled接口以及它们的邻居Local LDP Identifier: 23.1.1.3:0/LDP RID已经强制更改为F1/0接口地址 Discovery Sources: Interfaces: FastEthernet1/0 (ldp): xmit/recv Enabled: Interface config Hello interval: 5000 ms; Transport IP addr: 23.1.1.3 /用于建立TCP连接，发送Hello包的地址 LDP Id: 2.2.2.2:0 Src IP addr: 23.1.1.2; Transport IP addr: 2.2.2.2 Hold time: 15 sec; Proposed local/peer: 15/15 sec Reachable via 2.2.2.2/32运行LDP的路由器（LSR）都有一个LDP 路由器标识符（RID）。这个LDP RID是一个6字节的字段，其中包含4字节用来唯一标识该LSR的标识符（IP地址）和2字节用于标识LSR的标签空间。最后2个字节若为0，则是基于每台设备的标签空间；如果不为0，则是基于每个接口的标签空间。基于每个接口的标签空间是使用在LC-ATM链路。LDP RID的选举规则如下：（1）如果由mpls ldp router-id命令指定了某个接口的地址作为RID，且该接口有IP地址、处于UP状态，则用该接口作为RID；否则，如果有配了IP地址的Loopback接口，用所有Loopback 接口的IP地址中最大的IP地址作为RID；再则，选取所有配了IP地址、处于UP状态的接口的IP地址中最大的IP地址作为RID。（2）如果没有force可选参数，mpls ldp router-id命令指定的RID要到下一次路由器ID选举时才生效。路由器ID选举会发生在如下情况：（A）LDP重启动；（B）当前RID的接口关闭（shut down）；（C）当前RID的接口地址被删除。（3）当带有force可选参数时，mpls ldp router-id命令的效果取决于所指定接口的当前状态：如果指定的接口处UP于状态，而且其地址不是当前的RID，路由器强制将RID改变为指定值，同时中断所有当前的会话，释放由会话学习到的标签，中断与这些标签绑定有关的MPLS转发；如果指定的接口处于Down状态，一旦其变为UP状态，路由器强制将RID改变为指定值，同时中断所有当前的会话，释放由会话学习到的标签，中断与这些标签绑定有关的MPLS转发。注：LDP RID必须可达才能建立TCP会话。3.5 修改LDP Transport-AddressR3(config-if)#mpls ldp discovery transport-address 3.3.3.3R3(config-if)#*Mar 1 02:17:50.571: %LDP-5-NBRCHG: LDP Neighbor 2.2.2.2:0 (1) is DOWN (Received error notification from peer: Holddown time expir)R3(config-if)#*Mar 1 02:17:57.619: %LDP-5-NBRCHG: LDP Neighbor 2.2.2.2:0 (1) is UPR3#show mpls ldp discovery detail Local LDP Identifier: 23.1.1.3:0 Discovery Sources: Interfaces: FastEthernet1/0 (ldp): xmit/recv Enabled: Interface config Hello interval: 5000 ms; Transport IP addr: 3.3.3.3 LDP Id: 2.2.2.2:0 Src IP addr: 23.1.1.2; Transport IP addr: 2.2.2.2 Hold time: 15 sec; Proposed local/peer: 15/15 sec Reachable via 2.2.2.2/32LDP会话时在两台LSR的Transport IP地址之间建立起来的TCP连接，通常这些Transport IP地址都是LDP RID的IP地址。当然，可以在路由器接口上也可对其进行修改，这个Transport IP地址将包含在LDP的Hello消息中，并且从启用了LDP的接口发送出去。3.6 修改LDP Hello TimeR1(config)#mpls ldp discovery hello interval 4/修改LDP Hello间隔，默认为5秒R1#show mpls ldp discovery detailLocal LDP Identifier: 23.1.1.3:0 Discovery Sources: Interfaces: FastEthernet1/0 (ldp): xmit/recv Enabled: Interface config Hello interval: 4000 ms; Transport IP addr: 3.3.3.3 LDP Id: 2.2.2.2:0 Src IP addr: 23.1.1.2; Transport IP addr: 2.2.2.2 Hold time: 15 sec; Proposed local/peer: 15/15 sec Reachable via 2.2.2.2/32R2#show mpls ldp discovery detail Local LDP Identifier: 2.2.2.2:0 Discovery Sources: Interfaces: FastEthernet0/0 (ldp): xmit/recv Enabled: Interface config Hello interval: 5000 ms; Transport IP addr: 2.2.2.2 LDP Id: 1.1.1.1:0 Src IP addr: 12.1.1.1; Transport IP addr: 1.1.1.1 Hold time: 15 sec; Proposed local/peer: 15/15 sec Reachable via 1.1.1.1/32 FastEthernet1/0 (ldp): xmit/recv Enabled: Interface config Hello interval: 5000 ms; Transport IP addr: 2.2.2.2 LDP Id: 3.3.3.3:0 Src IP addr: 23.1.1.3; Transport IP addr: 3.3.3.3 Hold time: 15 sec; Proposed local/peer: 15/15 sec Reachable via 3.3.3.3/32修改LDP Hello Time之后，Hold Time不会自动更改。同时，邻居的LDP Hello Time和Hold Time不会被更改。如果Hello Time修改超过5秒，将