Cisco Systems 12.4 manual

MPLS LDP Configuration Guide, Cisco IOS Release 12.4 Americas Headquarters Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134-1706 USA http://www.cisco.com Tel: 408 526-4000 800 553-NETS (6387) Fax: 408 527-0883[...]

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C O N T E N T S MPLS Label Distribution Protocol (LDP) 1 Finding Feature Information 1 Prerequisites for MPLS LDP 1 Information About MPLS LDP 1 Introduction to MPLS LDP 2 MPLS LDP Functional Overview 2 LDP and TDP Support 2 Introduction to LDP Sessions 3 Directly Connected MPLS LDP Sessions 3 Nondirectly Connected MPLS LDP Sessions 4 Introduction [...]

Enabling MPLS LDP Session Protection 33 Verifying MPLS LDP Session Protection 35 Troubleshooting Tips 36 Configuration Examples for MPLS LDP Session Protection 36 Additional References 39 Command Reference 40 MPLS LDP Inbound Label Binding Filtering 41 Finding Feature Information 41 Restrictions 41 Information about MPLS LDP Inbound Label Binding F[...]

MPLS LDP Graceful Restart 65 Finding Feature Information 65 Restrictions 65 Information About MPLS LDP Graceful Restart 66 How MPLS LDP Graceful Restart Works 66 How a Route Processor Advertises That It Supports MPLS LDP Graceful Restart 67 What Happens If a Route Processor Does Not Have LDP Graceful Restart 67 How to Configure MPLS LDP Graceful Re[...]

Contents MPLS LDP Configuration Guide, Cisco IOS Release 12.4 vi[...]

MPLS Label Distribution Pr otocol (LDP) Multiprotocol Label Switching (MPLS) Label Distribution Protocol (LDP) enables peer label switch routers (LSRs) in an MPLS network to exchange label binding information for supporting hop-by-hop forwarding in an MPLS network. This module explains the concepts related to MPLS LDP and describes how to configure[...]

Introduction to MPLS LDP MPLS LDP provides the means for LSRs to request, distribute, and release label prefix binding information to peer routers in a network. LDP enables LSRs to discover potential peers and to establish LDP sessions with those peers for the purpose of exchanging label binding information. MPLS LDP enables one LSR to inform anoth[...]

Train and Release LDP/TDP Support 12.2S, SB, and SR Trains • LDP is enabled by default. • Cisco IOS Release 12.2(25)S and earlier releases: TDP is supported for LDP features. • Cisco IOS Releases 12.2(27)SBA, 12.2(27)SRA, 12.2(27)SRB and later releases: TDP is not supported for LDP features. 12.T/Mainline Trains • Cisco IOS Release 12.3(14)[...]

Nondirectly Connected MPLS LDP Sessions If the LSR is more than one hop from its neighbor, it is nondirectly connected to its neighbor. For these nondirectly connected neighbors, the LSR sends out a targeted Hello message as a UDP packet, but as a unicast message specifically addressed to that LSR. The nondirectly connected LSR responds to the Hell[...]

• Platform-wide--An LDP platform supports a single platform-wide label space for use by interfaces that can share the same labels. For Cisco platforms, all interface types, except LC-ATM, use the platform- wide label space. LDP uses a 6-byte quantity called an LDP Identifier (or LDP ID) to name label spaces. The LDP ID is made up of the following[...]

• Establishing Nondirectly Connected MPLS LDP Sessions, page 8 • Saving Configurations MPLS Tag Switching Commands, page 11 • Specifying the LDP Router ID, page 12 • Preserving QoS Settings with MPLS LDP Explicit Null, page 14 • Protecting Data Between LDP Peers with MD5 Authentication, page 18 Enabling Directly Connected LDP Sessi ons Th[...]

Command or Action Purpose Step 4 mpls label protocol {ldp | tdp | both} Example: Router(config)# mpls label protocol ldp Configures the use of LDP on all interfaces. LDP is the default. • If you set all interfaces globally to LDP, you can override specific interfaces with either the tdp or both keyword by specifying the command in interface confi[...]

Command or Action Purpose Step 11 show mpls ldp neighbor [[ vrf vpn-name ] [ address | interface ] [ detail ] | [ all ]] Example: Router# show mpls ldp neighbor Displays the status of LDP sessions. Examples The following show mpls interfaces command verifies that interfaces Ethernet 1/0 and 1/1 have been configured to use LDP: Router# show mpls int[...]

SUMMARY STEPS 1. enable 2. configure terminal 3. mpls ip 4. mpls label protocol {ldp | tdp | both} 5. interface tunnelnumber 6. tunnel destination ip-address 7. mpls ip 8. exit 9. exit 10. show mpls ldp discovery [ all | vrf vpn-name ] [ detail DETAILED STEPS Command or Action Purpose Step 1 enable Example: Router> enable Enables privileged EXEC[...]

Command or Action Purpose Step 5 interface tunnelnumber Example: Router(config)# interface tunnel1 Configures a tunnel interface and enters interface configuration mode. Step 6 tunnel destination ip-address Example: Router(config-if)# tunnel destination 172.16.1.1 Assigns an IP address to the tunnel interface. Step 7 mpls ip Example: Router(config-[...]

Interfaces: POS2/0 (ldp): xmit/recv LDP Id: 172.31.255.255:0 Tunnel1 (ldp): Targeted -> 192.168.255.255 Targeted Hellos: 172.16.0.0 -> 192.168.255.255 (ldp): active, xmit/recv LDP Id: 192.168.255.255:0 172.16.0.0 -> 192.168.0.0 (tdp): passive, xmit/recv TDP Id: 192.168.0.0:0 This command output indicates that: • The local LSR (172.16.0.0[...]

ip unnumbered Loopback0 mpls ip mpls label protocol ldp Specifying the LDP Router ID The mpls ldp router-id command allows you to establish the IP address of an interface as the LDP router ID. The following steps describe the normal process for determining the LDP router ID: 1 The router considers all the IP addresses of all operational interfaces.[...]

SUMMARY STEPS 1. enable 2. configure terminal 3. mpls ip 4. mpls label protocol { ldp | tdp | both } 5. mpls ldp router-id interface [ force ] 6. exit 7. show mpls ldp discovery [ all | detail | vrf vpn-name ] DETAILED STEPS Command or Action Purpose Step 1 enable Example: Router> enable Enables privileged EXEC mode. • Enter your password if p[...]

Command or Action Purpose Step 6 exit Example: Router(config)# exit Exits global configuration mode and enters privileged EXEC mode. Step 7 show mpls ldp discovery [ all | detail | vrf vpn- name ] Example: Router# show mpls ldp discovery Displays the LDP identifier for the local router. Example The following example assigns interface pos2/0/0 as th[...]

SUMMARY STEPS 1. enable 2. configure terminal 3. mpls ip 4. mpls label protocol { ldp | tdp | both } 5. interface type number 6. mpls ip 7. exit 8. mpls ldp explicit-null [ for prefix-acl | to peer-acl | for prefix-acl to peer-acl ] 9. exit 10. show mpls forwarding-table [ network { mask | length } | labels label [- label ] | interface interface | [...]

Command or Action Purpose Step 5 interface type number Example: Router(config)# interface atm2/0 Specifies the interface to be configured and enters interface configuration mode. Step 6 mpls ip Example: Router(config-if)# mpls ip Configures MPLS hop-by-hop forwarding on the interface. • You must enable MPLS forwarding on the interfaces as well as[...]

Examples Enabling explicit-null on an egress LSR causes that LSR to advertise the explicit-null label to all adjacent MPLS routers. Router# configure terminal Router(config)# mpls ldp explicit-null If you issue the show mpls forwarding-table command on an adjacent router, the output shows that MPLS packets are forwarded with an explicit-null label [...]

Router# configure terminal Router(config)# mpls label protocol ldp Router(config)# access-list 15 permit host 10.15.15.15 Router(config)# mpls ldp explicit-null to 15 If you issue the show mpls forwarding-table command, the output shows that explicit null labels are going only to the router specified in the access list. Router# show mpls forwarding[...]

If a router has a password configured for a neighbor, but the neighboring router does not have a password configured, a message such as the following appears on the console who has a password configured while the two routers attempt to establish an LDP session. The LDP session is not established. %TCP-6-BADAUTH: No MD5 digest from [peer's IP a[...]

Command or Action Purpose Step 5 mpls ldp neighbor [ vrf vpn-name ] ip- address [ password [ 0-7 ] password-string ] Example: Router(config)# mpls ldp neighbor 172.27.0.15 password onethirty9 Specifies authentication between two LDP peers. Step 6 exit Example: Router(config)# exit Exits global configuration mode and enters privileged EXEC mode. Ste[...]

Peer LDP Ident: 10.0.0.21:0; Local LDP Ident 10.0.0.22:0 TCP connection: 10.0.0.21.646 - 10.0.0.22.14709; MD5 on State: Oper; Msgs sent/rcvd: 1020/1019; Downstream; Last TIB rev sent 2034 Up time: 00:00:39; UID: 3; Peer Id 1; LDP discovery sources: FastEthernet1/1; Src IP addr: 172.16.1.1 holdtime: 15000 ms, hello interval: 5000 ms Addresses bound [...]

Note The configuration examples below show only the commands related to configuring LDP for Router 1, Router 2, and Router 3 in the sample network shown in the figure above. Router 1 Configuration ip cef distributed !Assumes R1 supports distributed CEF interface Loopback0 !Loopback interface for LDP ID. ip address 172.16.0.11 255.255.255.255 ! inte[...]

!Use LDP (configured i/f default) interface POS3/0/1 ip address 192.168.0.44 255.0.0.0 mpls ip !Enable hop-by-hop MPLS forwarding mpls label protocol tdp !Use TDP for this interface The configuration of Router 2 also uses the mpls label protocol ldp command in interface configuration mode. To specify LDP for all interfaces, use the mpls label proto[...]

global configuration mode makes it unnecessary to explicitly specify LDP as part of the configuration from the Tunnel14 and Tunnel16. ip cef distributed !Router1 supports distributed CEF mpls label protocol ldp !Use LDP as default for all interfaces interface Loopback0 !Loopback interface for LDP ID. ip address 10.25.0.11 255.255.255.255 interface [...]

Additional References Related Documents Related Topic Document Title Configures LDP on every interface associated with a specified IGP instance. MPLS LDP Autoconfiguration Ensures that LDP is fully established before the IGP path is used for switching. MPLS LDP-IGP Synchronization Allows ACLs to control the label bindings that an LSR accepts from i[...]

Technical Assistance Description Link The Cisco Technical Support website contains thousands of pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content. http://www.cisco.com/techsupport Feature Information[...]

Table 2 Feature Information for MPLS Label Distribution Protocol Overview Feature Name Releases Feature Information MPLS Label Distribution Protocol 12.0(10)ST 12.0(14)ST 12.1(2)T 12.1(8a)E 12.2(2)T 12.2(4)T 12.2(8)T 12.0(21)ST 12.0(22)S 12.0(23)S 12.2(13)T 12.4(3) 12.4(5) This feature was introduced in Cisco IOS Release 12.0(10)ST, incorporating a[...]

Feature Name Releases Feature Information In Cisco IOS Release 12.2(4)T, support was added for Cisco MGX 8850 and MGX 8950 switches equipped with a Cisco MGX RPM-PR card, and the VPI range in the show mpls atm-ldp bindings and show mpls ip binding commands was changed to 4095. In Cisco IOS Release 12.2(8)T, the debug mpls atm-ldp failure command wa[...]

Feature Name Releases Feature Information rather than the tag-switching form. Previously, commands were saved by using the tag- switching form of the command, for backward compatibility. See the Saving Configurations MPLS Tag Switching Commands, page 11 for more information. In Cisco IOS Release 12.4(5), the vrf vrf-name keyword/argument pair was a[...]

Establishing Nondirectly Connected MPLS LDP Sessions Example MPLS LDP Configuration Guide, Cisco IOS Release 12.4 30[...]

MPLS LDP Session Protectio n The MPLS LDP Session Protection feature provides faster label distribution protocol convergence when a link recovers following an outage. MPLS LDP Session Protection protects a label distribution protocol (LDP) session between directly connected neighbors or an LDP session established for a traffic engineering (TE) tunn[...]

• If the LSR is one hop from its neighbor, it is directly connected to its neighbor. The LSR sends out LDP Hello messages as User Datagram Protocol (UDP) packets to all the routers on the subnet. The hello message is called an LDP Link Hello. A neighboring LSR responds to the hello message and the two routers begin to establish an LDP session. ?[...]

How to Configure MPLS LD P Session Protection • Enabling MPLS LDP Session Protection, page 33 • Verifying MPLS LDP Session Protection, page 35 • Troubleshooting Tips, page 36 Enabling MPLS LDP Session Protection You use the mpls ldp session protection command to enable MPLS LDP Session Protection. This command enables LDP sessions to be prote[...]

Command or Action Purpose Step 2 configure terminal Example: Router# configure terminal Enters global configuration mode. Step 3 ip cef [ distributed ] Example: Router(config)# ip cef Configures Cisco Express Forwarding. Step 4 interface loopback number Example: Router(config)# interface Loopback0 Configures a loopback interface and enters interfac[...]

Command or Action Purpose Step 9 exit Example: Router(config-if)# exit Exits from interface configuration mode. Step 10 mpls ldp session protection [ vrf vpn-name ] [ for acl ] [ duration seconds ] Example: Router(config)# mpls ldp session protection Enables MPLS LDP Session Protection. Verifying MPLS LDP Session Protectio n SUMMARY STEPS 1. show m[...]

Up time: 21:09:56 LDP discovery sources: Targeted Hello 10.0.0.5 -> 10.0.0.3, active Addresses bound to peer LDP Ident: 10.3.104.3 10.0.0.2 10.0.0.3 Step 3 show mpls ldp neighbor detail Issue this command to check that the MPLS LDP Session Protection state is Ready or Protecting. If the second last line of the output shows Incomplete, the Target[...]

mode hsa ! ip cef distributed no ip domain-lookup multilink bundle-name both mpls label protocol ldp mpls ldp session protection no mpls traffic-eng auto-bw timers frequency 0 tag-switching tdp router-id Loopback0 force ! interface Loopback0 ip address 10.0.0.1 255.255.255.255 no ip directed-broadcast no ip mroute-cache ! interface Multilink4 no ip[...]

! ip subnet-zero ip cef distributed mpls label protocol ldp mpls ldp session protection no mpls traffic-eng auto-bw timers frequency 0 tag-switching tdp router-id Loopback0 force ! interface Loopback0 ip address 10.0.0.3 255.255.255.255 no ip directed-broadcast ! interface Ethernet5/0/0 no ip address no ip directed-broadcast shutdown full-duplex ! [...]

interface Ethernet1/4 ip address 10.0.0.2 255.0.0.0 no ip directed-broadcast full-duplex mpls label protocol ldp tag-switching ip ! router ospf 100 log-adjacency-changes redistribute connected network 10.0.0.5 0.0.0.0 area 100 network 10.0.0.0 0.255.255.255 area 100 network 10.0.0.0 0.255.255.255 area 100 ! ip classless Additional References Relate[...]

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MPLS LDP Inbound Label Bin ding Filtering Multiprotocol Label Switching (MPLS) Label Distribution Protocol (LDP) supports inbound label binding filtering. You can use the MPLS LDP Inbound Label Binding Filtering feature to configure access control lists (ACLs) for controlling the label bindings a label switch router (LSR) accepts from its peer LSRs[...]

How to Configure MPLS LD P Inbound Label Binding Fil tering • Configuring MPLS LDP Inbound Label Binding Filtering, page 42 • Verifying that MPLS LDP Inbound Label Bindings are Filtered, page 44 Configuring MPLS LDP Inbound Label Binding Filtering Perform this task to configure a router for inbound label filtering. The following configuration a[...]

Command or Action Purpose Step 3 ip access-list standard access-list-number Example: Example: Router(config)# ip access-list standard 1 Defines a standard IP access list with a number. Step 4 permit { source [ source-wildcard ] | any } [ log ] Example: Example: Router(config-std-nacl)# permit 10.0.0.0 Specifies one or more prefixes permitted by the[...]

Verifying that MPLS LDP Inbound Labe l Bindings are Filtered If inbound filtering is enabled, perform the following steps to verify that inbound label bindings are filtered: SUMMARY STEPS 1. Enter the show mpls ldp neighbor command to show the status of the LDP session, including the name or number of the ACL configured for inbound filtering. 2. En[...]

access-list-number | access-list-name ] Note It is important that you enter this command to see how the access list is defined; otherwise, you cannot verify inbound label binding filtering. The following command output shows the contents of IP access list 1: Example: Router# show ip access 1 Standard IP access list 1 permit 10.0.0.0, wildcard bits [...]

In the following example, the show mpls ldp bindings neighbor command displays label bindings that were learned from 10.110.0.10. This example verifies that the LIB does not contain label bindings for prefixes that have been excluded. Router# show mpls ldp bindings neighbor 10.110.0.10 tib entry: 10.2.0.0/16, rev 4 remote binding: tsr: 10.110.0.10:[...]

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Table 3 Feature Information for MPLS LDP Inbound Label Binding Filtering Feature Feature Name Releases Feature Information MPLS LDP Inbound Label Binding Filtering Feature 12.0(26)S 12.2(25)S 12.3(14)T 12.2(18)SXE You can use the MPLS LDP Inbound Label Binding Filtering feature to configure access control lists (ACLs) for controlling the label bind[...]

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Verifying that MPLS LDP Inbound Label Bindings are Filtered MPLS LDP Configuration Guide, Cisco IOS Release 12.4 50[...]

MPLS LDP Autoconfiguration The MPLS LDP Autoconfiguration feature enables you to globally configure Label Distribution Protocol (LDP) on every interface associated with a specified Interior Gateway Protocol (IGP) instance. • Finding Feature Information, page 51 • Restrictions for MPLS LDP Autoconfiguration , page 51 • Information About MPLS L[...]

Information About MPLS L DP Autoconfiguration To enable LDP, you should configure it globally and on each interface where it is needed. Configuring LDP on many interfaces can be time-consuming. The following section provides information about autoconfiguration feature on OSPF and IS-IS interfaces: • MPLS LDP Autoconfiguration on OSPF and IS-IS In[...]

DETAILED STEPS Command or Action Purpose Step 1 enable Example: Router> enable Enables privileged EXEC mode. • Enter your password if prompted. Step 2 configure terminal Example: Router# configure terminal Enters global configuration mode. Step 3 mpls ip Example: Router(config)# mpls ip Globally enables hop-by-hop forwarding. Step 4 mpls label[...]

Command or Action Purpose Step 8 router ospf process-id Example: Router(config)# router ospf 1 Enables OSPF routing and enters router configuration mode. Step 9 network ip-address wildcard-mask area area-id Example: Router(config-router)# network 10.0.0.0 0.0.255.255 area 3 Specifies the interface on which OSPF runs and defines the area ID for that[...]

DETAILED STEPS Command or Action Purpose Step 1 enable Example: Router> enable Enables privileged EXEC mode. • Enter your password if prompted. Step 2 configure terminal Example: Router# configure terminal Enters global configuration mode. Step 3 interface type number Example: Router(config)# interface POS 3/0 Specifies the interface to config[...]

Enables privileged EXEC mode. Enter your password if prompted. Step 2 show mpls interfaces [ type number | vrf vpn-name ][ all ] [ detail ] [ internal ] The show mpls interfaces command displays the method used to enable LDP on an interface: • If LDP is enabled by the mpls ldp autoconfig command, the output displays: Example: IP labeling enabled [...]

Serial2/0 (ldp): xmit/recv Enabled: Interface config, IGP config; Hello interval: 5000 ms; Transport IP addr: 10.11.11.11 LDP Id: 10.10.10.10:0 Src IP addr: 10.0.0.1; Transport IP addr: 10.10.10.10 Hold time: 15 sec; Proposed local/peer: 15/15 sec Configuring MPLS LDP Autoconfiguratio n with IS-IS Interfaces The following steps explain how to confi[...]

Command or Action Purpose Step 3 interface type number Example: Router(config)# interface POS 0/2 Specifies the interface to configure and enters interface configuration mode. Step 4 ip address prefix mask Example: Router(config-if)# ip address 10.50.72.4 255.0.0.0 Assigns an IP address to the interface. Step 5 ip router isis Example: Router(config[...]

Command or Action Purpose Step 10 mpls ldp autoconfig [level-1 | level-2] Example: Router(config-router)# mpls ldp autoconfig Enables the LDP for interfaces that belong to an IS-IS process. Step 11 end Example: Router(config-router)# end Exits router configuration mode and returns to privileged EXEC mode. Disabling MPLS LDP Autoconfiguration from S[...]

Command or Action Purpose Step 3 interface type number Example: Router(config)# interface POS 3/0 Specifies the interface to configure and enters interface configuration mode. Step 4 no mpls ldp igp autoconfig Example: Router(config-if)# no mpls ldp igp autoconfig Disables LDP for that interface. Step 5 end Example: Router(config-if)# end Exits int[...]

• IS-IS is up. • LDP is enabled. If the MPLS LDP Autoconfiguration feature is not enabled on an interface, the output looks like the following: Example: Interface: Ethernet0; ISIS tag null enabled ISIS is UP on interface AUTOCONFIG Information : LDP enabled: NO SYNC Information : Required: NO • Troubleshooting Tips, page 61 Troubleshooting Ti[...]

mpls ldp autoconfig area 3 end interface POS 1/0 no mpls ldp igp autoconfig MPLS LDP Autoconfiguration with IS- IS Examples The following example shows the configuration of the MPLS LDP Autoconfiguration feature on POS0/2 and 0/3 interfaces, which are running IS-IS processes: configure terminal interface POS 0/2 ip address 10.0.0.1 255.0.0.1 ip rou[...]

MIBs MIB MIBs Link MPLS LDP MIB To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL: http://www.cisco.com/go/mibs RFCs RFC Title RFC 3036 LDP Specification RFC 3037 LDP Applicability Technical Assistance Description Link The Cisco Support website provides extensi[...]

Table 4 Feature Information for MPLS LDP Autoconfiguration Feature Name Releases Feature Information MPLS LDP Autoconfiguration 12.0(30)S 12.0(32)SY 12.2(28)SB 12.2(33)SRB 12.3(14)T 15.0(1)M 12.2(33)XNE This feature enables you to globally configure LDP on every interface associated with a specified Interior Gateway Protocol (IGP) instance. In Cisc[...]

MPLS LDP Graceful Restart When a router is configured with Multiprotocol Label Switching (MPLS) Label Distribution Protocol (LDP) Graceful Restart (GR), it assists a neighboring router that has MPLS LDP Stateful Switchover/ Nonstop Forwarding (SSO/NSF) Support and Graceful Restart to recover gracefully from an interruption in service. In this Cisco[...]

• MPLS LDP GR is supported in strict helper mode. • Tag Distribution Protocol (TDP) sessions are not supported. Only LDP sessions are supported. • MPLS LDP GR cannot be configured on label-controlled ATM (LC-ATM) interfaces. • MPLS LDP SSO/NSF is supported in IOS Release 12.2(25)S. It is not supported in this release. Information About MPLS[...]

• mpls ldp graceful-restart timers neighbor-liveness • mpls ldp graceful-restart timers max-recovery How a Route Processor Advertises Tha t It Supports MPLS LDP Graceful Restart A route processor that is configured to perform MPLS LDP GR includes the Fault Tolerant (FT) Type Length Value (TLV) in the LDP initialization message. The route proces[...]

SUMMARY STEPS 1. enable 2. configure terminal 3. ip cef [ distributed ] 4. mpls ldp graceful-restart 5. interface type slot/port 6. mpls ip 7. mpls label protocol { ldp | tdp | both } DETAILED STEPS Command or Action Purpose Step 1 enable Example: Router> enable Enables privileged EXEC mode. • Enter your password if prompted. Step 2 configure [...]

Command or Action Purpose Step 6 mpls ip Example: Router(config-if)# mpls ip Configures MPLS hop-by-hop forwarding for an interface. Step 7 mpls label protocol { ldp | tdp | both } Example: Router(config-if)# mpls label protocol ldp Configures the use of LDP for an interface. You must use LDP. Note You can also issue the mpls label protocol ldp com[...]

Router 1 configured with LDP GR: boot system slot0:rsp-pv-mz hw-module slot 2 image slot0:rsp-pv-mz hw-module slot 3 image slot0:rsp-pv-mz ! ip subnet-zero ip cef mpls label range 16 10000 static 10001 1048575 mpls label protocol ldp mpls ldp logging neighbor-changes mpls ldp graceful-restart mpls traffic-eng tunnels no mpls traffic-eng auto-bw tim[...]

mpls ldp logging neighbor-changes mpls ldp graceful-restart mpls traffic-eng tunnels no mpls traffic-eng auto-bw timers frequency 0 no mpls advertise-labels mpls ldp router-id Loopback0 force ! interface Loopback0 ip address 17.17.17.17 255.255.255.255 no ip directed-broadcast ! interface ATM4/0/0 no ip address no ip directed-broadcast no ip mroute[...]

no mpls traffic-eng auto-bw timers frequency 0 mpls ldp discovery directed-hello interval 12 mpls ldp discovery directed-hello holdtime 130 mpls ldp discovery directed-hello accept mpls ldp router-id Loopback0 force ! interface Loopback0 ip address 19.19.19.19 255.255.255.255 no ip directed-broadcast ! interface POS1/0 ip address 11.0.0.2 255.0.0.0[...]

RFCs RFCs 2 Title RFC 3036 LDP Specification RFC 3478 Graceful Restart Mechanism for Label Distribution Technical Assistance Description Link The Cisco Technical Support & Documentation website contains thousands of pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered[...]

Table 5 Feature Information for MPLS LDP Graceful Restart Feature Name Releases Feature Information MPLS LDP Graceful Restart 12.0(29)S 12.3(14)T 12.2(33)SRA MPLS LDP Graceful Restart assists a neighboring router that has MPLS LDP Stateful Switchover/Nonstop Forwarding (SSO/NSF) Support and Graceful Restart to recover gracefully from an interruptio[...]