Feedback
|
Table Of Contents
MPLS VPN—Carrier Supporting Carrier—IPv4 BGP Label Distribution
Using BGP to Distribute Routes and MPLS Labels for the Customer Carrier Who Is an ISP
How BGP Sends MPLS Labels with Routes
Using Route Maps to Filter Routes
Related Features and Technologies
Supported Standards, MIBs, and RFCs
Configuring the CSC-PE Routers to Exchange IPv4 Routes and MPLS Labels
Configuring the CSC-CE Routers to Exchange IPv4 Routes and MPLS Labels
Configuring a Route Map for Arriving Routes
Configuring a Route Map for Departing Routes
Applying the Route Maps to the CSC-PE Routers
Applying the Route Maps to the CSC-CE Routers
Verifying the CE1 Router Configuration
Verifying the PE1 Router Configuration
Verifying the CSC-CE1 Router Configuration
Verifying the CSC-PE1 Router Configuration
Verifying the CSC-PE2 Router Configuration
Verifying the CSC-CE2 Router Configuration
Verifying the PE2 Router Configuration
Verifying the CE2 Router Configuration
MPLS VPN—Carrier Supporting Carrier—IPv4 BGP Label Distribution
Feature History
Release Modification12.0(21)ST
This feature was introduced.
12.0(22)S
This feature was integrated into Cisco IOS Release 12.0(22)S. Support for the Cisco 12000 series routers (for specific line cards supported, see Table 1) was added.
12.0(23)S
This feature was integrated into Cisco IOS Release 12.0(23)S. Support for the Cisco 12000 Series Eight-Port OC-3c/STM-1c ATM Line Card (8-Port OC-3 ATM) and the Cisco 12000 Series Three-Port Gigabit Ethernet Line Card (3-Port GbE) was added.
This feature enables you to configure your carrier supporting carrier network to enable Border Gateway Protocol (BGP) to transport routes and Multiprotocol Label Switching (MPLS) labels between the backbone carrier provider edge (PE) routers and the customer carrier customer edge (CE) routers. Previously you had to use Label Distribution Protocol (LDP) to carry the labels and an internal gateway protocol (IGP) to carry the routes between PE and CE routers to achieve the same goal.
This feature is an extension of the Carrier Supporting Carrier feature, introduced in the 12.0(14)ST, which was based on LDP. See MPLS VPN Carrier Supporting Carrier for more information.
This feature module includes the following sections:
•
Supported Standards, MIBs, and RFCs
Feature Overview
This feature enables you to configure a carrier supporting carrier network that uses BGP to distribute routes and MPLS labels between the PE and CE routers of a backbone carrier and a customer carrier. The backbone carrier offers BGP and MPLS VPN services. The customer carrier can be either:
•
An Internet service provider (ISP) with an IP core
•
An MPLS service provider with or without VPN services
This document describes how to use BGP to distribute MPLS labels and routes for both types of customer carrier.
Using BGP to Distribute Routes and MPLS Labels for the Customer Carrier Who Is an ISP
Figure 1 shows a network configuration where the customer carrier is an ISP. The customer carrier has two sites, each of which is a point of presence (POP). The customer carrier connects these sites using a VPN service provided by the backbone carrier. The backbone carrier uses MPLS. The ISP sites use IP.
Figure 1 Network Where the Customer Carrier Is an ISP
In this configuration, the links between the CE and PE routers use EBGP to distribute IPv4 routes and MPLS labels. Between the links, the PE routers use multiprotocol IBGP to distribute VPNv4 routes.
Note
If a non-Cisco router is used as a CSC-PE or CSC-CE, that router must support IPv4 BGP label distribution (RFC 3107). Otherwise, you cannot run EBGP with labels between the routers.
Using BGP to Distribute Routes and MPLS Labels for a Customer Carrier Who Is an MPLS VPN Service Provider
Figure 2 shows a network configuration where the backbone carrier and the customer carrier are BGP/MPLS VPN service providers. The customer carrier has two sites. Both the backbone carrier and the customer carrier use MPLS in their networks.
Figure 2 Network Where the Customer Carrier Is an MPLS VPN Service Provider
In this configuration, the customer carrier can configure their network in one of the following ways:
•
The customer carrier can run IGP and LDP in its core network. In this case, the customer carrier's CSC-CE1 router redistributes the EBGP routes it learned from the backbone carrier's CSC-PE1 to IGP.
•
The customer carrier's CSC-CE1 router can run IPv4 + labels IBGP session with the PE1 router.
BGP Overview
BGP routing information includes the following items:
•
A network number (prefix), which is the IP address of the destination.
•
Autonomous system (AS) path, which is a list of the other ASs through which a route passes on its way to the local router. The first AS in the list is closest to the local router; the last AS in the list is farthest from the local router and usually the AS where the route began.
•
Path attributes, which provide other information about the AS path, for example, the next hop.
Types of BGP Messages
MPLS labels are included in the "update" messages that a router sends. Routers exchange the following types of BGP messages:
•
Open Messages—After a router establishes a TCP connection with a neighboring router, the routers exchange "open" messages. This message contains the AS number to which the router belongs and the IP address of the router who sent the message.
•
Update Messages—When a router has a new, changed, or broken route, it sends an "update" message to the neighboring router. This message contains the Network Layer Reachability Information (NLRI), which lists the IP addresses of the usable routes. The update message also includes any routes that are no longer usable. The update message also includes path attributes and the lengths of both the usable and unusable paths. Labels for VPNv4 routes are encoded in the update message as specified in RFC 2858. The labels for the IPv4 routes are encoded in the update message as specified in RFC 3107.
•
Keepalive Messages—Routers exchange "keepalive" messages to determine if a neighboring router is still available to exchange routing information. The router sends these messages at regular intervals. (Sixty seconds is the default for Cisco routers.) The keepalive message does not contain routing data; it only contains a message header.
•
Notification Messages—When a router detects an error, it sends a "notification" message.
How BGP Sends MPLS Labels with Routes
When BGP (both External BGP (EBGP) and Internal BGP (IBGP)) distributes a route, it can also distribute an MPLS label that is mapped to that route. The MPLS label mapping information for the route is carried in the BGP update message that contains the information about the route. If the next hop is not changed, the label is preserved.
When you issue the neighbor send-label command on both BPG routers, the routers advertise to each other that they can then send MPLS labels with the routes. If the routers successfully negotiate their ability to send MPLS labels, the routers add MPLS labels to all outgoing BGP updates.
Using Route Maps to Filter Routes
When both routers are configured to distribute routes with MPLS labels, all the routes are encoded with the multiprotocol extensions and contain an MPLS label. You can use a route map to control the distribution of MPLS labels between routers. Route maps enable you to specify the following:
•
For a router distributing MPLS labels, you can specify which routes are distributed with an MPLS label.
•
For a router receiving MPLS labels, you can specify which routes are accepted and installed in the BGP table.
Benefits
Using BGP to distribute IPv4 routes and MPLS labels routes has the following benefits:
•
BGP takes the place of an IGP and LDP. You can use BGP to distribute routes and MPLS labels. Using a single protocol instead of two simplifies the configuration and troubleshooting.
•
BGP is the preferred routing protocol for connecting two ISPs, mainly because of its routing policies and ability to scale. ISPs commonly use BGP between two providers. This feature enables those ISPs to use BGP.
Restrictions
This feature includes the following restrictions:
•
On a PE router, an interface can be configured for either BGP with labels or LDP. You cannot enable both protocols on the same interface. If you switch from one protocol to the other, then the existing protocol must be disabled on all interfaces before you enable the other protocol.
•
This feature does not currently support multiple BGP routes to a given destination with different MPLS labels as described in Section 4 of RFC 3107.
•
EBGP multihop between CSC-PE and CSC-CE is not supported for this release.
•
This feature is not supported with eiBGP multipath.
•
The physical interfaces that connect the BGP speakers must support Cisco Express Forwarding (CEF) or distributed Cisco Express Forwarding (DCEF) and MPLS.
Related Features and Technologies
The MPLS VPN Carrier Supporting Carrier feature is used with the VPN capabilities of MPLS. MPLS VPNs were introduced in Cisco IOS Release 12.0(5)T.
This feature is an extension of the feature MPLS VPN Carrier Supporting Carrier, Cisco IOS Release 12.0(14)ST.
Related Documents
•
MPLS VPN Carrier Supporting Carrier
•
Cisco IOS IP Configuration Guide, Release 12.2, Configuring BGP chapter
•
Using the Border Gateway Protocol for Interdomain Routing
•
Internetworking Technology Overview, Border Gateway Protocol chapter
•
Cisco IOS Switching Services Configuration Guide, Release 12.2, Configuring Multiprotocol Label Switching chapter
•
Cisco IOS IP Command Reference, Volume 2 of 3: Routing Protocols, Release 12.2, BGP Commands chapter
•
MPLS Virtual Private Networks (VPNs)
Supported Platforms
The following router platforms are supported at the service provider edge:
•
Cisco 7200 series
•
Cisco 7500 series
•
Cisco 12000 series routers
See Table 1 for Cisco 12000 series line card support added for Cisco IOS Releases.
Determining Platform Support Through Cisco Feature Navigator
Cisco IOS software is packaged in feature sets that are supported on specific platforms. To get updated information regarding platform support for this feature, access Cisco Feature Navigator. Cisco Feature Navigator dynamically updates the list of supported platforms as new platform support is added for the feature.
Cisco Feature Navigator is a web-based tool that enables you to determine which Cisco IOS software images support a specific set of features and which features are supported in a specific Cisco IOS image. You can search by feature or release. Under the release section, you can compare releases side by side to display both the features unique to each software release and the features in common.
To access Cisco Feature Navigator, you must have an account on Cisco.com. If you have forgotten or lost your account information, send a blank e-mail to cco-locksmith@cisco.com. An automatic check will verify that your e-mail address is registered with Cisco.com. If the check is successful, account details with a new random password will be e-mailed to you. Qualified users can establish an account on Cisco.com by following the directions found at this URL:
Cisco Feature Navigator is updated regularly when major Cisco IOS software releases and technology releases occur. For the most current information, go to the Cisco Feature Navigator home page at the following URL:
Availability of Cisco IOS Software Images
Platform support for particular Cisco IOS software releases is dependent on the availability of the software images for those platforms. Software images for some platforms may be deferred, delayed, or changed without prior notice. For updated information about platform support and availability of software images for each Cisco IOS software release, refer to the online release notes or, if supported, Cisco Feature Navigator.
Supported Standards, MIBs, and RFCs
Standards
No new or modified standards are supported by this feature.
MIBs
No new or modified MIBs are supported by this feature.
To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:
http://tools.cisco.com/ITDIT/MIBS/servlet/index
If Cisco MIB Locator does not support the MIB information that you need, you can also obtain a list of supported MIBs and download MIBs from the Cisco MIBs page at the following URL:
http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml
To access Cisco MIB Locator, you must have an account on Cisco.com. If you have forgotten or lost your account information, send a blank e-mail to cco-locksmith@cisco.com. An automatic check will verify that your e-mail address is registered with Cisco.com. If the check is successful, account details with a new random password will be e-mailed to you. Qualified users can establish an account on Cisco.com by following the directions found at this URL:
RFCs
•
RFC 3107, Carrying Label Information in BGP-4
•
RFC 2858, Multiprotocol Extensions for BGP-4
•
RFC 1700, Assigned Numbers
•
RFC 2842, Capabilities Advertisement with BGP-4
•
RFC 1966, BGP Route Reflection: An Alternative to Full Mesh IBGP
•
RFC 1171, A Border Gateway Protocol 4
•
RFC 1164, Application of the Border Gateway Protocol in the Internet
•
RFC 2283, Multiprotocol Extensions for BGP-4
•
RFC 2547, BGP/MPLS VPNs
Prerequisites
•
The network must be properly configured for MPLS VPN operation before you configure this feature.
•
Make sure that the CSC-PE and CSC-CE routers run images that support BGP label distribution. Otherwise, you cannot run EBGP between them.
Configuration Tasks
See the following sections for configuration tasks for this feature. Each task in the list is identified as either required or optional.
•
Configuring the CSC-PE Routers to Exchange IPv4 Routes and MPLS Labels (required)
•
Configuring the CSC-CE Routers to Exchange IPv4 Routes and MPLS Labels (required)
•
Creating Route Maps (optional)
•
Applying the Route Maps to the CSC-PE Routers (optional)
•
Applying the Route Maps to the CSC-CE Routers (optional)
•
Verifying the Configuration (optional)
Configuring the CSC-PE Routers to Exchange IPv4 Routes and MPLS Labels
To configure the CSC-PEs so that they can distribute BGP routes with MPLS labels, use the following commands beginning in user EXEC mode:
Configuring the CSC-CE Routers to Exchange IPv4 Routes and MPLS Labels
To configure the CSC-CE routers so that they can distribute BGP routes with MPLS labels, use the following commands beginning in user EXEC mode:
Creating Route Maps
The following procedures enable the routers to send MPLS labels with the routes specified in the route maps. Further, the routers accept the only routes that are specified in the route map.
Route maps enable you to specify which routes are distributed with MPLS labels. Route maps also enable you to specify which routes with MPLS labels a router receives and adds to its BGP table.
Route maps work with access lists. You enter the routes into an access list and then specify the access list when you configure the route map.
Configuring a Route Map for Arriving Routes
To configure a route map to filter for arriving routes, use the following commands beginning in user EXEC mode. You create an access list and specify the routes that the router should accept and add to the BGP table.
Configuring a Route Map for Departing Routes
To configure a route map to filter for departing routes, use the following commands beginning in user EXEC mode. You create an access list and specify the routes that the router should distribute with MPLS labels.
Applying the Route Maps to the CSC-PE Routers
To enable the CSC-PE routers to use the route maps, use the following commands beginning in user EXEC mode:
Applying the Route Maps to the CSC-CE Routers
To enable the CSC-CE routers to use the route maps, use the following commands beginning in user EXEC mode:
Verifying the Configuration
This section explains how to check that the customer and backbone carrier routers are configured to enable BGP to distribute routes and MPLS labels. Use Figure 3 as a reference for verifying the configuration.
Figure 3 Configuring CSC Routers to Exchange IPv4 Routes and MPLS Labels
Verifying the CE1 Router Configuration
Step 1
Verify that the loopback address of the remote CE router (CE2), learned from the PE router, is in the routing table of the CE1 router.
Router# show ip route jj.jj.jj.jjRouting entry for jj.jj.jj.jj/32Known via "bgp 300", distance 20, metric 0Tag 200, type externalRedistributing via ospf 300Advertised by ospf 300 subnetsLast update from mm.0.0.1 20:29:35 agoRouting Descriptor Blocks:* mm.0.0.1, from mm.0.0.1, 20:29:35 agoRoute metric is 0, traffic share count is 1AS Hops 2
Verifying the PE1 Router Configuration
Step 1
Verify that the loopback address of the local CE router (CE1) is in the routing table of the PE1 router.
Router# show ip route vrf <PE-vrf-name> aa.aa.aa.aaRouting entry for aa.aa.aa.aa/32Known via "bgp 200", distance 20, metric 0Tag 300, type externalLast update from mm.0.0.2 20:36:59 agoRouting Descriptor Blocks:* mm.0.0.2, from mm.0.0.2, 20:36:59 agoRoute metric is 0, traffic share count is 1AS Hops 1, BGP network version 0Step 2
Verify that the prefix for the local CE router (CE1) is in the MPLS forwarding table, and that the prefix is untagged.
Router# show mpls forwarding-table vrf <PE-vrf-name> aa.aa.aa.aaLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface23 Untagged aa.aa.aa.aa/32[V] 0 Et3/3 mm.0.0.2Step 3
Verify that the prefix of the remote PE router (PE2) is in the Cisco Express Forwarding (CEF) table.
Router# show ip cef hh.hh.hh.hhhh.hh.hh.hh/32, version 31, cached adjacency nn.0.0.20 packets, 0 bytestag information setlocal tag: 31fast tag rewrite with Et3/0, nn.0.0.2, tags imposed {26}via nn.0.0.2, Ethernet3/0, 2 dependenciesnext hop nn.0.0.2, Ethernet3/0unresolvedvalid cached adjacencytag rewrite with Et3/0, nn.0.0.2, tags imposed {26}Step 4
Verify that the loopback address of the remote CE router (CE2) is in the routing table.
Router# show ip route vrf <PE-vrf-name> jj.jj.jj.jjRouting entry for jj.jj.jj.jj/32Known via "bgp 200", distance 200, metric 0Tag 300, type internalLast update from hh.hh.hh.hh 20:38:49 agoRouting Descriptor Blocks:* hh.hh.hh.hh (Default-IP-Routing-Table), from hh.hh.hh.hh, 20:38:49 agoRoute metric is 0, traffic share count is 1AS Hops 1, BGP network version 0Step 5
Verify that the prefix of the remote CE router (CE2) is in the MPLS forwarding table, and that an outgoing interface exists.
Router# show mpls forwarding-table vrf <PE-vrf-name> jj.jj.jj.jjLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interfaceNone 26 jj.jj.jj.jj/32 0 Et3/0 nn.0.0.2Step 6
Verify that the prefix of the remote CE router (CE2) is in the CEF table.
Router# show ip cef vrf <PE-vrf-name> jj.jj.jj.jjjj.jj.jj.jj/32, version 12, cached adjacency nn.0.0.20 packets, 0 bytestag information setlocal tag: VPN route headfast tag rewrite with Et3/0, nn.0.0.2, tags imposed {26 32}via hh.hh.hh.hh, 0 dependencies, recursivenext hop nn.0.0.2, Ethernet3/0 via hh.hh.hh.hh/32valid cached adjacencytag rewrite with Et3/0, nn.0.0.2, tags imposed {26 32}Step 7
Verify that the prefix of the local PE router (PE1) is in the CEF table.
Router# show ip cef bb.bb.bb.bbbb.bb.bb.bb/32, version 9, connected, receivetag information setlocal tag: implicit-null
Verifying the CSC-CE1 Router Configuration
Step 1
Verify that the BGP session is up and running.
Router# show ip bgp summaryBGP router identifier cc.cc.cc.cc, local AS number 200BGP table version is 35, main routing table version 3514 network entries and 14 paths using 2030 bytes of memory3 BGP path attribute entries using 168 bytes of memory1 BGP AS-PATH entries using 24 bytes of memory0 BGP route-map cache entries using 0 bytes of memory0 BGP filter-list cache entries using 0 bytes of memoryDampening enabled. 1 history paths, 0 dampened pathsBGP activity 17/67 prefixes, 29/15 paths, scan interval 60 secsNeighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcdpp.0.0.1 4 100 7615 7613 35 0 0 21:06:19 5Step 2
Verify that the loopback address of the local PE router (PE1) is in the routing table.
Router# show ip route bb.bb.bb.bbRouting entry for bb.bb.bb.bb/32Known via "ospf 200", distance 110, metric 101, type intra areaRedistributing via bgp 200Advertised by bgp 200 metric 4 match internalLast update from nn.0.0.1 on Ethernet4/0, 00:34:08 agoRouting Descriptor Blocks:* nn.0.0.1, from bb.bb.bb.bb, 00:34:08 ago, via Ethernet4/0Route metric is 101, traffic share count is 1Step 3
Verify that the loopback address of the remote PE router (PE2) is in the routing table.
Router# show ip route hh.hh.hh.hhRouting entry for hh.hh.hh.hh/32Known via "bgp 200", distance 20, metric 0Tag 100, type externalRedistributing via ospf 200Advertised by ospf 200 metric 3 subnetsLast update from pp.0.0.1 00:45:16 agoRouting Descriptor Blocks:* pp.0.0.1, from pp.0.0.1, 00:45:16 agoRoute metric is 0, traffic share count is 1AS Hops 2, BGP network version 0Step 4
Verify that the prefix of the local PE router (PE1) is in the MPLS LDP bindings.
Router# show mpls ldp bindings bb.bb.bb.bb 255.255.255.255tib entry: bb.bb.bb.bb/32, rev 20local binding: tag: 20remote binding: tsr: bb.bb.bb.bb:0, tag: imp-nullStep 5
Verify that the prefix of the local PE router (PE1) is in the CEF table.
Router# show ip cef bb.bb.bb.bbbb.bb.bb.bb/32, version 46, cached adjacency nn.0.0.10 packets, 0 bytestag information setlocal tag: 20via nn.0.0.1, Ethernet4/0, 0 dependenciesnext hop nn.0.0.1, Ethernet4/0unresolvedvalid cached adjacencytag rewrite with Et4/0, nn.0.0.1, tags imposed {}Step 6
Verify that the prefix of the local PE router (PE1) is in the MPLS forwarding table.
Router# show mpls forwarding-table bb.bb.bb.bbLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface20 Pop tag bb.bb.bb.bb/32 893397 Et4/0 nn.0.0.1Router# show mpls forwarding-table bb.bb.bb.bb detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface20 Pop tag bb.bb.bb.bb/32 893524 Et4/0 nn.0.0.1MAC/Encaps=14/14, MTU=1504, Tag Stack{}00074F83685400B04A74A0708847No output feature configuredPer-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Step 7
Verify that the BGP routing table contains labels for prefixes in the customer carrier MPLS VPN service provider networks.
Router# show ip bgp labelsNetwork Next Hop In Label/Out Labelcc.cc.cc.cc/32 0.0.0.0 imp-null/exp-nullbb.bb.bb.bb/32 nn.0.0.1 20/exp-nullhh.hh.hh.hh/32 pp.0.0.1 26/34gg.gg.gg.gg/32 pp.0.0.1 23/30nn.0.0.0 0.0.0.0 imp-null/exp-nullss.0.0.0 pp.0.0.1 25/33pp.0.0.0 0.0.0.0 imp-null/exp-nullpp.0.0.1/32 0.0.0.0 16/exp-nullStep 8
Verify that the prefix of the remote PE router (PE2) is in the CEF table.
Router# show ip cef hh.hh.hh.hhhh.hh.hh.hh/32, version 54, cached adjacency pp.0.0.10 packets, 0 bytestag information setlocal tag: 26fast tag rewrite with Et3/0, pp.0.0.1, tags imposed {34}via pp.0.0.1, 0 dependencies, recursivenext hop pp.0.0.1, Ethernet3/0 via pp.0.0.1/32valid cached adjacencytag rewrite with Et3/0, pp.0.0.1, tags imposed {34}Step 9
Verify that the prefix of the remote PE router (PE2) is in the MPLS forwarding table.
Router# show mpls forwarding-table hh.hh.hh.hhLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface26 34 hh.hh.hh.hh/32 81786 Et3/0 pp.0.0.1Router# show mpls forwarding-table hh.hh.hh.hh detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface26 34 hh.hh.hh.hh/32 81863 Et3/0 pp.0.0.1MAC/Encaps=14/18, MTU=1500, Tag Stack{34}00B0C26E105500B04A74A0548847 00022000No output feature configuredPer-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Verifying the CSC-PE1 Router Configuration
Step 1
Verify that the BGP session is up and running between the CSC-PE1 router and the CSC-CE1 router. Verify that prefixes are learned during each session, by checking the data in the State/PfxRcd column.
Router# show ip bgp vpnv4 all summaryBBGP router identifier dd.dd.dd.dd, local AS number 100BGP table version is 52, main routing table version 5212 network entries and 13 paths using 2232 bytes of memory6 BGP path attribute entries using 336 bytes of memory1 BGP AS-PATH entries using 24 bytes of memory1 BGP extended community entries using 24 bytes of memory0 BGP route-map cache entries using 0 bytes of memory0 BGP filter-list cache entries using 0 bytes of memoryDampening enabled. 0 history paths, 0 dampened pathsBGP activity 16/4 prefixes, 27/14 paths, scan interval 5 secsNeighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcdee.ee.ee.ee 4 100 7685 7686 52 0 0 21:17:04 6pp.0.0.2 4 200 7676 7678 52 0 0 21:16:43 7Step 2
Verify that the MPLS interfaces are up and running, and that LDP-enabled interfaces show that LDP is up and running. LDP is turned off on the VRF because EBGP distributes the labels.
Router# show mpls interfaces allInterface IP Tunnel OperationalGigabitEthernet6/0 Yes (ldp) No YesVRF vpn1:Ethernet3/1 No No YesStep 3
Verify that the prefix for the PE1 router is in the routing table of the CSC-PE1 router.
Router# show ip route vrf <CSC-PE-vrf-name> bb.bb.bb.bbRouting entry for bb.bb.bb.bb/32Known via "bgp 100", distance 20, metric 4Tag 200, type externalLast update from pp.0.0.2 21:28:39 agoRouting Descriptor Blocks:* pp.0.0.2, from pp.0.0.2, 21:28:39 agoRoute metric is 4, traffic share count is 1AS Hops 1, BGP network version 0Step 4
Verify that the prefix for the PE2 router is in the routing table of the CSC-PE1 router.
Router# show ip route vrf <CSC-PE-vrf-name> hh.hh.hh.hhRouting entry for hh.hh.hh.hh/32Known via "bgp 100", distance 200, metric 4Tag 200, type internalLast update from ee.ee.ee.ee 21:27:39 agoRouting Descriptor Blocks:* ee.ee.ee.ee (Default-IP-Routing-Table), from ee.ee.ee.ee, 21:27:39 agoRoute metric is 4, traffic share count is 1AS Hops 1, BGP network version 0Step 5
Verify that the prefixes for the customer carrier MPLS VPN service provider networks are in the BGP table, and have appropriate labels.
Router# show ip bgp vpnv4 vrf <CSC-PE-vrf-name> labelsNetwork Next Hop In label/Out labelRoute Distinguisher: 100:1 (vpn1)cc.cc.cc.cc/32 pp.0.0.2 22/imp-nullbb.bb.bb.bb/32 pp.0.0.2 27/20hh.hh.hh.hh/32 ee.ee.ee.ee 34/35gg.gg.gg.gg/32 ee.ee.ee.ee 30/30nn.0.0.0 pp.0.0.2 23/imp-nullss.0.0.0 ee.ee.ee.ee 33/34pp.0.0.0 pp.0.0.2 25/aggregate(vpn1)Step 6
Verify that the prefix of the PE router in the local customer carrier MPLS VPN service provider (PE1) is in the CEF table.
Router# show ip cef vrf <CSC-PE-vrf-name> bb.bb.bb.bbbb.bb.bb.bb/32, version 19, cached adjacency pp.0.0.20 packets, 0 bytestag information setlocal tag: 27fast tag rewrite with Et3/1, pp.0.0.2, tags imposed {20}via pp.0.0.2, 0 dependencies, recursivenext hop pp.0.0.2, Ethernet3/1 via pp.0.0.2/32valid cached adjacencytag rewrite with Et3/1, pp.0.0.2, tags imposed {20}Router# show ip cef vrf <CSC-PE-vrf-name> bb.bb.bb.bb detailbb.bb.bb.bb/32, version 19, cached adjacency pp.0.0.20 packets, 0 bytestag information setlocal tag: 27fast tag rewrite with Et3/1, pp.0.0.2, tags imposed {20}via pp.0.0.2, 0 dependencies, recursivenext hop pp.0.0.2, Ethernet3/1 via pp.0.0.2/32valid cached adjacencytag rewrite with Et3/1, pp.0.0.2, tags imposed {20}Step 7
Verify that the prefix of the PE router in the local customer carrier MPLS VPN service provider (PE1) is in the MPLS forwarding table.
Router# show mpls forwarding-table vrf <CSC-PE-vrf-name> bb.bb.bb.bbLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface27 20 bb.bb.bb.bb/32[V] 958048 Et3/1 pp.0.0.2Router# show mpls forwarding-table vrf <CSC-PE-vrf-name> bb.bb.bb.bb detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface27 20 bb.bb.bb.bb/32[V] 958125 Et3/1 pp.0.0.2MAC/Encaps=14/18, MTU=1500, Tag Stack{20}00B04A74A05400B0C26E10558847 00014000VPN route: vpn1No output feature configuredPer-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Step 8
Verify that the prefix of the PE router in the remote customer carrier MPLS VPN service provider (PE2) is in the CEF table.
Router# show ip cef vrf <CSC-PE-vrf-name> hh.hh.hh.hhhh.hh.hh.hh/32, version 25, cached adjacency rr.0.0.20 packets, 0 bytestag information setlocal tag: 34fast tag rewrite with Gi6/0, rr.0.0.2, tags imposed {35}via ee.ee.ee.ee, 0 dependencies, recursivenext hop rr.0.0.2, GigabitEthernet6/0 via ee.ee.ee.ee/32valid cached adjacencytag rewrite with Gi6/0, rr.0.0.2, tags imposed {35}Router# show ip cef vrf <CSC-PE-vrf-name> hh.hh.hh.hh detailhh.hh.hh.hh/32, version 25, cached adjacency rr.0.0.20 packets, 0 bytestag information setlocal tag: 34fast tag rewrite with Gi6/0, rr.0.0.2, tags imposed {35}via ee.ee.ee.ee, 0 dependencies, recursivenext hop rr.0.0.2, GigabitEthernet6/0 via ee.ee.ee.ee/32valid cached adjacencytag rewrite with Gi6/0, rr.0.0.2, tags imposed {35}Step 9
Verify that the prefix of the PE router in the remote customer carrier MPLS VPN service provider (PE2) is in the MPLS forwarding table.
Router# show mpls forwarding-table vrf <CSC-PE-vrf-name> hh.hh.hh.hhLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface34 35 hh.hh.hh.hh/32[V] 139034 Gi6/0 rr.0.0.2Router# show mpls forwarding-table vrf <CSC-PE-vrf-name> hh.hh.hh.hh detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface34 35 hh.hh.hh.hh/32[V] 139034 Gi6/0 rr.0.0.2MAC/Encaps=14/18, MTU=1500, Tag Stack{35}00B0C26E447000B0C26E10A88847 00023000VPN route: vpn1No output feature configuredPer-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Verifying the CSC-PE2 Router Configuration
Step 1
Verify that the BGP session is up and running between the CSC-PE2 router and the CSC-CE2 router. Verify that prefixes are learned during each session, by checking the data in the State/PfxRcd column.
Router# show ip bgp vpnv4 all summaryBGP router identifier ee.ee.ee.ee, local AS number 100BGP table version is 51, main routing table version 5112 network entries and 13 paths using 2232 bytes of memory6 BGP path attribute entries using 336 bytes of memory1 BGP AS-PATH entries using 24 bytes of memory1 BGP extended community entries using 24 bytes of memory0 BGP route-map cache entries using 0 bytes of memory0 BGP filter-list cache entries using 0 bytes of memoryDampening enabled. 0 history paths, 0 dampened pathsBGP activity 16/4 prefixes, 31/18 paths, scan interval 5 secsNeighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcddd.dd.dd.dd 4 100 7901 7900 51 0 0 21:52:59 7ss.0.0.2 4 200 7871 7880 51 0 0 21:50:15 6Step 2
Verify that the MPLS interfaces are up and running, and that LDP-enabled interfaces show that LDP is up and running. LDP is turned off on the VRF because EBGP distributes the labels.
Router# show mpls interfaces allInterface IP Tunnel OperationalGigabitEthernet4/0 Yes (ldp) No YesVRF vpn1:Ethernet5/0 No No YesStep 3
Verify that the prefix of the PE1 router is in the routing table of the CSC-PE2 router.
Router# show ip route vrf <CSC-PE-vrf-name> bb.bb.bb.bb.bbRouting entry for bb.bb.bb.bb/32Known via "bgp 100", distance 200, metric 4Tag 200, type internalLast update from dd.dd.dd.dd 21:53:30 agoRouting Descriptor Blocks:* dd.dd.dd.dd (Default-IP-Routing-Table), from dd.dd.dd.dd, 21:53:30 agoRoute metric is 4, traffic share count is 1AS Hops 1, BGP network version 0Step 4
Verify that the prefix of the PE2 router is in the routing table of the CSC-PE2 router.
Router# show ip route vrf <CSC-PE-vrf-name> hh.hh.hh.hhRouting entry for hh.hh.hh.hh/32Known via "bgp 100", distance 20, metric 4Tag 200, type externalLast update from ss.0.0.2 21:53:12 agoRouting Descriptor Blocks:* ss.0.0.2, from ss.0.0.2, 21:53:12 agoRoute metric is 4, traffic share count is 1AS Hops 1, BGP network version 0Step 5
Verify that the prefixes for the customer carrier MPLS VPN service provider networks are in the BGP routing table, and that the prefixes have appropriate labels.
Router# show ip bgp vpnv4 vrf <CSC-PE-vrf-name> labelsNetwork Next Hop In label/Out labelRoute Distinguisher: 100:1 (vpn1)cc.cc.cc.cc/32 dd.dd.dd.dd 27/22bb.bb.bb.bb/32 dd.dd.dd.dd 26/27hh.hh.hh.hh/32 ss.0.0.2 35/31gg.gg.gg.gg/32 ss.0.0.2 30/imp-nullnn.0.0.0 dd.dd.dd.dd 24/23ss.0.0.0 ss.0.0.2 34/aggregate(vpn1)pp.0.0.0 dd.dd.dd.dd 21/25Step 6
Verify that the prefix of the PE router in the remote customer carrier MPLS VPN service provider (PE1) is in the CEF table.
Router# show ip cef vrf <CSC-PE-vrf-name> bb.bb.bb.bbbb.bb.bb.bb/32, version 15, cached adjacency rr.0.0.10 packets, 0 bytestag information setlocal tag: 26fast tag rewrite with Gi4/0, rr.0.0.1, tags imposed {27}via dd.dd.dd.dd, 0 dependencies, recursivenext hop rr.0.0.1, GigabitEthernet4/0 via dd.dd.dd.dd/32valid cached adjacencytag rewrite with Gi4/0, rr.0.0.1, tags imposed {27}Router# show ip cef vrf <CSC-PE-vrf-name> bb.bb.bb.bb detailbb.bb.bb.bb/32, version 15, cached adjacency rr.0.0.10 packets, 0 bytestag information setlocal tag: 26fast tag rewrite with Gi4/0, rr.0.0.1, tags imposed {27}via dd.dd.dd.dd, 0 dependencies, recursivenext hop rr.0.0.1, GigabitEthernet4/0 via dd.dd.dd.dd/32valid cached adjacencytag rewrite with Gi4/0, rr.0.0.1, tags imposed {27}Step 7
Verify that the prefix of the PE router in the remote customer carrier MPLS VPN service provider (PE1) is in the MPLS forwarding table.
Router# show mpls forwarding-table vrf <CSC-PE-vrf-name> bb.bb.bb.bbLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface26 27 bb.bb.bb.bb/32[V] 967450 Gi4/0 rr.0.0.1Router# show mpls forwarding-table vrf <CSC-PE-vrf-name> bb.bb.bb.bb detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface26 27 bb.bb.bb.bb/32[V] 967510 Gi4/0 rr.0.0.1MAC/Encaps=14/18, MTU=1500, Tag Stack{27}00B0C26E10A800B0C26E44708847 0001B000VPN route: vpn1No output feature configuredPer-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1572k-131-9#Step 8
Verify that the prefix of the PE router in the local customer carrier MPLS VPN service provider (PE2) is in the CEF table.
Router# show ip cef vrf <CSC-PE-vrf-name> hh.hh.hh.hhhh.hh.hh.hh/32, version 33, cached adjacency ss.0.0.20 packets, 0 bytestag information setlocal tag: 35fast tag rewrite with Et5/0, ss.0.0.2, tags imposed {31}via ss.0.0.2, 0 dependencies, recursivenext hop ss.0.0.2, Ethernet5/0 via ss.0.0.2/32valid cached adjacencytag rewrite with Et5/0, ss.0.0.2, tags imposed {31}Router# show ip cef vrf <CSC-PE-vrf-name> hh.hh.hh.hh detailhh.hh.hh.hh/32, version 33, cached adjacency ss.0.0.20 packets, 0 bytestag information setlocal tag: 35fast tag rewrite with Et5/0, ss.0.0.2, tags imposed {31}via ss.0.0.2, 0 dependencies, recursivenext hop ss.0.0.2, Ethernet5/0 via ss.0.0.2/32valid cached adjacencytag rewrite with Et5/0, ss.0.0.2, tags imposed {31}Step 9
Verify that the prefix of the PE router in the local customer carrier MPLS VPN service provider (PE2) is in the MPLS forwarding table.
Router# show mpls forwarding-table vrf <CSC-PE-vrf-name> hh.hh.hh.hhLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface35 31 hh.hh.hh.hh/32[V] 2023332 Et5/0 ss.0.0.2Router# show mpls forwarding-table vrf <CSC-PE-vrf-name> hh.hh.hh.hh detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface35 31 hh.hh.hh.hh/32[V] 2023469 Et5/0 ss.0.0.2MAC/Encaps=14/18, MTU=1500, Tag Stack{31}0030A363380300B0C26E448C8847 0001F000VPN route: vpn1No output feature configuredPer-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Verifying the CSC-CE2 Router Configuration
Step 1
Verify that the BGP session is up and running.
Router# show ip bgp summaryBGP router identifier gg.gg.gg.gg, local AS number 200BGP table version is 31, main routing table version 3113 network entries and 13 paths using 1885 bytes of memory3 BGP path attribute entries using 168 bytes of memory1 BGP AS-PATH entries using 24 bytes of memory0 BGP route-map cache entries using 0 bytes of memory0 BGP filter-list cache entries using 0 bytes of memoryDampening enabled. 0 history paths, 0 dampened pathsBGP activity 17/4 prefixes, 20/7 paths, scan interval 60 secsNeighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcdss.0.0.1 4 100 7962 7953 31 0 0 22:03:55 6Step 2
Verify that the loopback address of the local PE router (PE2) is in the routing table.
Router# show ip route hh.hh.hh.hhRouting entry for hh.hh.hh.hh/32Known via "ospf 200", distance 110, metric 7, type intra areaRedistributing via bgp 200Advertised by bgp 200 metric 4 match internalLast update from 19.19.19.19 on ATM3/1/0.1, 01:37:02 agoRouting Descriptor Blocks:* hh.hh.hh.hh, from hh.hh.hh.hh, 01:37:02 ago, via ATM3/1/0.1Route metric is 7, traffic share count is 1Step 3
Verify that the loopback address of the remote PE router (PE1) is in the routing table.
Router# show ip route bb.bb.bb.bbRouting entry for bb.bb.bb.bb/32Known via "bgp 200", distance 20, metric 0Tag 100, type externalRedistributing via ospf 200Advertised by ospf 200 metric 3 subnetsLast update from ss.0.0.1 22:04:44 agoRouting Descriptor Blocks:* ss.0.0.1, from ss.0.0.1, 22:04:44 agoRoute metric is 0, traffic share count is 1AS Hops 2, BGP network version 0Step 4
Verify that the prefix of the local PE router (PE2) is in the MPLS LDP bindings.
Router# show mpls ldp bindings hh.hh.hh.hh 255.255.255.255tib entry: hh.hh.hh.hh/32, rev 37local binding: tag: 31Router# show mpls ldp bindings hh.hh.hh.hh 255.255.255.255 detailtib entry: hh.hh.hh.hh/32, rev 37local binding: tag: 31Step 5
Verify that the prefix of the local PE (PE2) is in the CEF table.
Router# show ip cef hh.hh.hh.hhhh.hh.hh.hh/32, version 31, cached adjacency to ATM3/1/0.10 packets, 0 bytestag information setlocal tag: 31fast tag rewrite with AT3/1/0.1, point2point, tags imposed {2/33(vcd=2)}via hh.hh.hh.hh, ATM3/1/0.1, 0 dependenciesnext hop hh.hh.hh.hh, ATM3/1/0.1unresolvedvalid cached adjacencytag rewrite with AT3/1/0.1, point2point, tags imposed {2/33(vcd=2)}Router# show ip cef hh.hh.hh.hh detailhh.hh.hh.hh/32, version 31, cached adjacency to ATM3/1/0.10 packets, 0 bytestag information setlocal tag: 31fast tag rewrite with AT3/1/0.1, point2point, tags imposed {2/33(vcd=2)}via hh.hh.hh.hh, ATM3/1/0.1, 0 dependenciesnext hop hh.hh.hh.hh, ATM3/1/0.1unresolvedvalid cached adjacencytag rewrite with AT3/1/0.1, point2point, tags imposed {2/33(vcd=2)}Step 6
Verify that the prefix of the local PE router (PE2) is in the MPLS forwarding table.
Router# show mpls forwarding-table hh.hh.hh.hhLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface31 2/33 hh.hh.hh.hh/32 1908083 AT3/1/0.1 point2pointRouter# show mpls forwarding-table hh.hh.hh.hh detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface31 2/33 hh.hh.hh.hh/32 1908200 AT3/1/0.1 point2pointMAC/Encaps=4/8, MTU=4470, Tag Stack{2/33(vcd=2)}00028847 00002000No output feature configuredPer-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Step 7
Verify that the BGP routing table contains labels for prefixes in the customer carrier MPLS VPN service provider networks.
Router# show ip bgp labelsNetwork Next Hop In Label/Out Labelcc.cc.cc.cc/32 ss.0.0.1 18/27bb.bb.bb.bb/32 ss.0.0.1 19/26hh.hh.hh.hh/32 hh.hh.hh.hh 31/exp-nullgg.gg.gg.gg/32 0.0.0.0 imp-null/exp-nullnn.0.0.0 ss.0.0.1 22/24ss.0.0.0 0.0.0.0 imp-null/exp-nullss.0.0.1/32 0.0.0.0 16/exp-nullpp.0.0.0 ss.0.0.1 26/21Step 8
Verify that the prefix of the remote PE router (PE1) is in the CEF table.
Router# show ip cef bb.bb.bb.bbbb.bb.bb.bb/32, version 18, cached adjacency ss.0.0.10 packets, 0 bytestag information setlocal tag: 19fast tag rewrite with Et0/0/3, ss.0.0.1, tags imposed {26}via ss.0.0.1, 0 dependencies, recursivenext hop ss.0.0.1, Ethernet0/0/3 via ss.0.0.1/32valid cached adjacencytag rewrite with Et0/0/3, ss.0.0.1, tags imposed {26}Router# show ip cef bb.bb.bb.bb detailbb.bb.bb.bb/32, version 18, cached adjacency ss.0.0.10 packets, 0 bytestag information setlocal tag: 19fast tag rewrite with Et0/0/3, ss.0.0.1, tags imposed {26}via ss.0.0.1, 0 dependencies, recursivenext hop ss.0.0.1, Ethernet0/0/3 via ss.0.0.1/32valid cached adjacencytag rewrite with Et0/0/3, ss.0.0.1, tags imposed {26}Step 9
Verify that the prefix of the remote PE router (PE1) is in the MPLS forwarding table.
Router# show mpls forwarding-table bb.bb.bb.bbLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface19 26 bb.bb.bb.bb/32 965401 Et0/0/3 ss.0.0.1Router# show mpls forwarding-table bb.bb.bb.bb detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface19 26 bb.bb.bb.bb/32 965478 Et0/0/3 ss.0.0.1MAC/Encaps=14/18, MTU=1500, Tag Stack{26}00B0C26E448C0030A36338038847 0001A000No output feature configuredPer-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Verifying the PE2 Router Configuration
Step 1
Verify that the loopback address of the local CE router (CE2) is in the routing table of the PE2 router.
Router# show ip route vrf <PE-vrf-name> jj.jj.jj.jjRouting entry for jj.jj.jj.jj/32Known via "bgp 200", distance 20, metric 0Tag 300, type externalLast update from tt.0.0.2 22:11:06 agoRouting Descriptor Blocks:* tt.0.0.2, from tt.0.0.2, 22:11:06 agoRoute metric is 0, traffic share count is 1AS Hops 1, BGP network version 0Step 2
Verify that the prefix of the local CE router (CE2) is in the MPLS forwarding table, and is untagged.
Router# show mpls forwarding-table vrf <PE-vrf-name> jj.jj.jj.jjLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface32 Untagged jj.jj.jj.jj/32[V] 0 Et3/6 tt.0.0.2Router# show mpls forwarding-table vrf <PE-vrf-name> jj.jj.jj.jj detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interface32 Untagged jj.jj.jj.jj/32[V] 0 Et3/6 tt.0.0.2MAC/Encaps=0/0, MTU=1504, Tag Stack{}VPN route: vpn2No output feature configuredPer-packet load-sharing, slots: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Step 3
Verify that the prefix of the remote PE router (PE1) is in the CEF table.
Router# show ip cef bb.bb.bb.bbbb.bb.bb.bb/32, version 19, cached adjacency to ATM5/0.10 packets, 0 bytestag information setlocal tag: 20fast tag rewrite with AT5/0.1, point2point, tags imposed {2/35(vcd=6)}via gg.gg.gg.gg, ATM5/0.1, 2 dependenciesnext hop gg.gg.gg.gg, ATM5/0.1unresolvedvalid cached adjacencytag rewrite with AT5/0.1, point2point, tags imposed {2/35(vcd=6)}Router# show ip cef bb.bb.bb.bb detailbb.bb.bb.bb/32, version 19, cached adjacency to ATM5/0.10 packets, 0 bytestag information setlocal tag: 20fast tag rewrite with AT5/0.1, point2point, tags imposed {2/35(vcd=6)}via gg.gg.gg.gg, ATM5/0.1, 2 dependenciesnext hop gg.gg.gg.gg, ATM5/0.1unresolvedvalid cached adjacencytag rewrite with AT5/0.1, point2point, tags imposed {2/35(vcd=6)}Step 4
Verify that the loopback address of the remote CE router (CE1) is in the routing table.
Router# show ip route vrf <PE-vrf-name> aa.aa.aa.aaRouting entry for aa.aa.aa.aa/32Known via "bgp 200", distance 200, metric 0Tag 300, type internalLast update from bb.bb.bb.bb 01:43:34 agoRouting Descriptor Blocks:* bb.bb.bb.bb (Default-IP-Routing-Table), from bb.bb.bb.bb, 01:43:34 agoRoute metric is 0, traffic share count is 1AS Hops 1, BGP network version 0Step 5
Verify that the prefix of the remote CE router (CE1) is in the MPLS forwarding table, and that it has an outgoing interface.
Router# show mpls forwarding-table vrf <PE-vrf-name> aa.aa.aa.aaLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interfaceNone 2/35 aa.aa.aa.aa/32 0 AT5/0.1 point2pointRouter# show mpls forwarding-table vrf <PE-vrf-name> aa.aa.aa.aa detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interfaceNone 2/35 aa.aa.aa.aa/32 0 AT5/0.1 point2pointMAC/Encaps=4/12, MTU=4466, Tag Stack{2/35(vcd=6) 23}00068847 0000600000017000No output feature configuredStep 6
Verify that the prefix of the remote CE router (CE1) is in the CEF table.
Router# show ip cef vrf <PE-vrf-name> aa.aa.aa.aaaa.aa.aa.aa/32, version 10, cached adjacency to ATM5/0.10 packets, 0 bytestag information setlocal tag: VPN route headfast tag rewrite with AT5/0.1, point2point, tags imposed {2/35(vcd=6) 23}via bb.bb.bb.bb, 0 dependencies, recursivenext hop gg.gg.gg.gg, ATM5/0.1 via bb.bb.bb.bb/32valid cached adjacencytag rewrite with AT5/0.1, point2point, tags imposed {2/35(vcd=6) 23}Router# show ip cef vrf <PE-vrf-name> aa.aa.aa.aa detailaa.aa.aa.aa/32, version 10, cached adjacency to ATM5/0.10 packets, 0 bytestag information setlocal tag: VPN route headfast tag rewrite with AT5/0.1, point2point, tags imposed {2/35(vcd=6) 23}via bb.bb.bb.bb, 0 dependencies, recursivenext hop gg.gg.gg.gg, ATM5/0.1 via bb.bb.bb.bb/32valid cached adjacencytag rewrite with AT5/0.1, point2point, tags imposed {2/35(vcd=6) 23}Step 7
Verify that the prefix of the local PE router (PE2) is in the CEF table.
Router# show ip cef hh.hh.hh.hhhh.hh.hh.hh/32, version 9, connected, receivetag information setlocal tag: implicit-nullRouter# show ip cef hh.hh.hh.hh detailhh.hh.hh.hh/32, version 9, connected, receivetag information setlocal tag: implicit-null
Verifying the CE2 Router Configuration
Step 1
Verify that the loopback address of the remote CE router (CE1), learned from the PE router, is in the routing table of the CE2 router.
Router# show ip route aa.aa.aa.aaRouting entry for aa.aa.aa.aa/32Known via "bgp 300", distance 20, metric 0Tag 200, type externalRedistributing via ospf 300Advertised by ospf 300 subnetsLast update from tt.0.0.1 22:16:46 agoRouting Descriptor Blocks:* tt.0.0.1, from tt.0.0.1, 22:16:46 agoRoute metric is 0, traffic share count is 1AS Hops 2
Configuration Examples
This section includes the following configuration examples:
Configuration of BGP/MPLS Backbone Carrier Using BGP to Distribute MPLS Labels to an MPLS VPN Service Provider
This section provides a example of a backbone carrier and a customer carrier who are both BGP/MPLS VPN service providers. This configuration example shows how BGP is enabled to distribute routes and MPLS labels between PE and CE routers. Figure 4 shows the example configuration.
Figure 4 Network Where the Customer Carrier Is an MPLS VPN Service Provider
Table 2 describes the sample configuration shown in Figure 4.
Table 2 Description of Sample Configuration Shown in Figure 4
Routers DescriptionCE1 and CE2
Belong to an end customer. CE1 and CE2 routers exchange routes learned from PE routers.
The end customer is purchasing VPN services from a customer carrier.
PE1 and PE2
Part of a customer carrier network that is configured to provide MPLS VPN services. PE1 and PE2 are peering with a VPNv4 IBGP session to form a MPLS VPN network.
CSC-CE1 and CSC-CE2
Part of a customer carrier network. CSC-CE1 and CSC-CE2 routers exchange IPv4 BGP updates with MPLS labels and redistribute PE loopback addressees to and from the IGP (OSPF in this example).
The customer carrier is purchasing carrier supporting carrier VPN services from a backbone carrier.
CSC-PE1 and CSC-PE2
Part of the backbone carrier's network configured to provide carrier supporting carrier VPN services. CSC-PE1 and CSC-PE2 are peering with a VPNv4 IP BGP session to form the MPLS VPN network. In the VRF, CSC-PE1 and CSC-PE2 are peering with the CSC-CE routers, which are configured for carrying MPLS labels with the routes, with an IPv4 EBGP session.
CE1 Configuration
ip cefinterface Loopback0ip address aa.aa.aa.aa 255.255.255.255!interface Ethernet3/3ip address mm.0.0.1 255.0.0.0!router bgp 300no synchronizationbgp log-neighbor-changestimers bgp 10 30redistribute connected !Exchange routesneighbor mm.0.0.2 remote-as 200 !learned from PE1.neighbor mm.0.0.2 advertisement-interval 5no auto-summaryPE1 Configuration
ip cef!ip vrf vpn2rd 200:1route-target export 200:1route-target import 200:1mpls label protocol ldp!interface Loopback0ip address bb.bb.bb.bb 255.255.255.255!interface Ethernet3/0ip address nn.0.0.1 255.0.0.0no ip directed-broadcastno ip mroute-cachempls label protocol ldpmpls ip!interface Ethernet3/3ip vrf forwarding vpn2ip address mm.0.0.2 255.0.0.0no ip directed-broadcastno ip mroute-cache!router ospf 200log-adjacency-changesauto-cost reference-bandwidth 1000redistribute connected subnetspassive-interface Ethernet3/3network bb.bb.bb.bb 0.0.0.0 area 200network nn.0.0.0 0.255.255.255 area 200!router bgp 200no bgp default ipv4-unicastbgp log-neighbor-changestimers bgp 10 30neighbor hh.hh.hh.hh remote-as 200neighbor hh.hh.hh.hh update-source Loopback0!address-family vpnv4 !VPNv4 session with PE2.neighbor hh.hh.hh.hh activateneighbor hh.hh.hh.hh send-community extendedbgp dampening 30exit-address-family!address-family ipv4 vrf vpn2neighbor mm.0.0.1 remote-as 300neighbor mm.0.0.1 activateneighbor mm.0.0.1 as-overrideneighbor mm.0.0.1 advertisement-interval 5no auto-summaryno synchronizationbgp dampening 30exit-address-familyCSC-CE1 Configuration
ip cef!mpls label protocol ldp!interface Loopback0ip address cc.cc.cc.cc 255.255.255.255!interface Ethernet3/0ip address pp.0.0.1 255.0.0.0!interface Ethernet4/0ip address nn.0.0.2 255.0.0.0no ip directed-broadcastno ip mroute-cachempls label protocol ldpmpls ip!router ospf 200log-adjacency-changesauto-cost reference-bandwidth 1000redistribute connected subnets !Exchange routesredistribute bgp 200 metric 3 subnets !learned from PE1.passive-interface ATM1/0passive-interface Ethernet3/0network cc.cc.cc.cc 0.0.0.0 area 200network nn.0.0.0 0.255.255.255 area 200!router bgp 200no bgp default ipv4-unicastbgp log-neighbor-changestimers bgp 10 30neighbor pp.0.0.2 remote-as 100neighbor pp.0.0.2 update-source Ethernet3/0no auto-summary!address-family ipv4redistribute connectedredistribute ospf 200 metric 4 match internalneighbor pp.0.0.2 activateneighbor pp.0.0.2 send-labelno auto-summaryno synchronizationbgp dampening 30exit-address-familyCSC-PE1 Configuration
ip cef!ip vrf vpn1rd 100:1route-target export 100:1route-target import 100:1mpls label protocol ldp!interface Loopback0ip address dd.dd.dd.dd 255.255.255.255!interface Ethernet3/1ip vrf forwarding vpn1ip address pp.0.0.2 255.0.0.0!interface ATM0/1/0no ip addressno ip directed-broadcastno ip route-cache distributedatm clock INTERNALno atm enable-ilmi-trapno atm ilmi-keepalive!interface ATM0/1/0.1 mplsip unnumbered Loopback0no ip directed-broadcastno atm enable-ilmi-trapmpls label protocol ldpmpls atm vpi 2-5mpls ip!router ospf 100log-adjacency-changesauto-cost reference-bandwidth 1000redistribute connected subnetspassive-interface Ethernet3/1network dd.dd.dd.dd 0.0.0.0 area 100!router bgp 100no bgp default ipv4-unicastbgp log-neighbor-changestimers bgp 10 30neighbor ee.ee.ee.ee remote-as 100neighbor ee.ee.ee.ee update-source Loopback0!address-family vpnv4 !VPNv4 session with CSC-PE2.neighbor ee.ee.ee.ee activateneighbor ee.ee.ee.ee send-community extendedbgp dampening 30exit-address-family!address-family ipv4 vrf vpn1neighbor pp.0.0.1 remote-as 200neighbor pp.0.0.1 activateneighbor pp.0.0.1 as-overrideneighbor pp.0.0.1 advertisement-interval 5neighbor pp.0.0.1 send-labelno auto-summaryno synchronizationbgp dampening 30exit-address-familyCSC-PE2 Configuration
ip cef!ip vrf vpn1rd 100:1route-target export 100:1route-target import 100:1mpls label protocol ldp!interface Loopback0ip address ee.ee.ee.ee 255.255.255.255!interface Ethernet5/0ip vrf forwarding vpn1ip address ss.0.0.2 255.0.0.0no ip directed-broadcastno ip route-cache distributedclock source internal!interface ATM2/1/0no ip addressno ip directed-broadcastno ip route-cache distributedatm clock INTERNALno atm enable-ilmi-trapno atm ilmi-keepalive!interface ATM2/1/0.1 mplsip unnumbered Loopback0no ip directed-broadcastno atm enable-ilmi-trapmpls label protocol ldpmpls atm vpi 2-5mpls ip!router ospf 100log-adjacency-changesauto-cost reference-bandwidth 1000redistribute connected subnetspassive-interface Ethernet5/0passive-interface ATM3/0/0network ee.ee.ee.ee 0.0.0.0 area 100!router bgp 100no bgp default ipv4-unicastbgp log-neighbor-changestimers bgp 10 30neighbor dd.dd.dd.dd remote-as 100neighbor dd.dd.dd.dd update-source Loopback0!address-family vpnv4 !VPNv4 session with CSC-PE1.neighbor dd.dd.dd.dd activateneighbor dd.dd.dd.dd send-community extendedbgp dampening 30exit-address-family!address-family ipv4 vrf vpn1neighbor ss.0.0.1 remote-as 200neighbor ss.0.0.1 activateneighbor ss.0.0.1 as-overrideneighbor ss.0.0.1 advertisement-interval 5neighbor ss.0.0.1 send-labelno auto-summaryno synchronizationbgp dampening 30exit-address-familyCSC-CE2 Configuration
ip cef!mpls label protocol ldp!interface Loopback0ip address gg.gg.gg.gg 255.255.255.255!interface Ethernet2/2ip address ss.0.0.2 255.0.0.0no ip directed-broadcastno ip mroute-cachempls label protocol ldpmpls ip!interface ATM3/1/0.1 point2pointip address yy.0.0.1 255.0.0.0no ip directed-broadcastno atm enable-ilmi-trapno ip mroute-cache!router ospf 200log-adjacency-changesauto-cost reference-bandwidth 1000redistribute connected subnets !Exchange routesredistribute bgp 200 metric 3 subnets !learned from PE2.passive-interface ATM3/1/0.1network gg.gg.gg.gg 0.0.0.0 area 200network ss.0.0.0 0.255.255.255 area 200!router bgp 200no bgp default ipv4-unicastbgp log-neighbor-changestimers bgp 10 30neighbor yy.0.0.2 remote-as 100neighbor yy.0.0.2 update-source ATM3/1/0.1no auto-summary!address-family ipv4redistribute connectedredistribute ospf 200 metric 4 match internalneighbor yy.0.0.2 activateneighbor yy.0.0.2 send-labelno auto-summaryno synchronizationbgp dampening 30exit-address-familyPE2 Configuration
ip cef!ip vrf vpn2rd 200:1route-target export 200:1route-target import 200:1!mpls label protocol ldp!interface Loopback0ip address hh.hh.hh.hh 255.255.255.255!interface Ethernet3/6ip vrf forwarding vpn2ip address tt.0.0.2 255.0.0.0!interface ATM5/0.1 point2pointip address qq.0.0.1 255.0.0.0no ip directed-broadcastno atm enable-ilmi-trapno ip mroute-cachempls label protocol ldpmpls ip!router bgp 200no bgp default ipv4-unicastbgp log-neighbor-changestimers bgp 10 30neighbor bb.bb.bb.bb remote-as 200neighbor bb.bb.bb.bb update-source Loopback0!address-family vpnv4 !VPNv4 session with PE1.neighbor bb.bb.bb.bb activateneighbor bb.bb.bb.bb send-community extendedbgp dampening 30exit-address-family!address-family ipv4 vrf vpn2neighbor tt.0.0.1 remote-as 300neighbor tt.0.0.1 activateneighbor tt.0.0.1 as-overrideneighbor tt.0.0.1 advertisement-interval 5no auto-summaryno synchronizationbgp dampening 30exit-address-familyCE2 Configuration
ip cef!interface Loopback0ip address jj.jj.jj.jj 255.255.255.255!interface Ethernet3/6ip address tt.0.0.1 255.0.0.0!router bgp 300no synchronizationbgp log-neighbor-changestimers bgp 10 30 !Exchange routesredistribute connected !learned from PE2.redistribute ospf 300 match internal external 1 external 2neighbor tt.0.0.2 remote-as 200neighbor tt.0.0.2 advertisement-interval 5no auto-summaryConfiguration of Route Maps
The following example creates two route maps, which are named:
•
IN for incoming routes
•
OUT for outgoing routes
The route maps specify the following:
•
If an IP address in an incoming BGP update message matches an IP address in access list 99, the route is added to the BGP table.
•
If an IP address in an outbound BGP update message matches an IP address in access list 88, the router distributes that route.
The route maps are applied to the router with the address qq.0.0.1.
address-family ipv4 vrf vpn1neighbor qq.0.0.1 remote-as 200neighbor qq.0.0.1 activateneighbor qq.0.0.1 as-overrideneighbor qq.0.0.1 advertisement-interval 5neighbor qq.0.0.1 route-map IN inneighbor qq.0.0.1 route-map OUT outneighbor qq.0.0.1 send-label!access-list 88 permit rr.rr.rr.rraccess-list 88 permit ss.ss.ss.ssaccess-list 88 permit tt.tt.tt.ttaccess-list 99 permit uu.uu.uu.uuaccess-list 99 permit vv.vv.vv.vvaccess-list 99 permit ww.ww.ww.ww!route-map IN permit 1match ip address 99!route-map OUT permit 1match ip address 88set mpls-label!Command Reference
This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.2 command reference publications.
New Commands
Modified Commands
debug ip bgp
To display information related to processing of the Border Gateway Protocol (BGP), use the debug ip bgp command in privileged EXEC mode. To disable the display of BGP information, use the no form of this command.
debug ip bgp [A.B.C.D. | dampening | events | in | keepalives | out | updates | vpnv4 | mpls]
no debug ip bgp [A.B.C.D. | dampening | events | in | keepalives | out | updates | vpnv4 | mpls]
Syntax Description
Command Modes
Privileged EXEC
Command History
Examples
The following example displays the output from this command:
Router# debug ip bgp vpnv403:47:14:vpn:bgp_vpnv4_bnetinit:100:2:58.0.0.0/803:47:14:vpn:bnettable add:100:2:58.0.0.0 / 803:47:14:vpn:bestpath_hook route_tag_change for vpn2:58.0.0.0/255.0.0.0(ok)03:47:14:vpn:bgp_vpnv4_bnetinit:100:2:57.0.0.0/803:47:14:vpn:bnettable add:100:2:57.0.0.0 / 803:47:14:vpn:bestpath_hook route_tag_change for vpn2:57.0.0.0/255.0.0.0(ok)03:47:14:vpn:bgp_vpnv4_bnetinit:100:2:14.0.0.0/803:47:14:vpn:bnettable add:100:2:14.0.0.0 / 803:47:14:vpn:bestpath_hook route_tag_chacle ip bgp *nge for vpn2:14.0.0.0/255.0.0.0(ok)match mpls-label
To redistribute routes that include Multiprotocol Label Switching (MPLS) labels if the routes meet the conditions specified in the route map, use the match mpls-label command in route map configuration mode. To disable this function, use the no form of this command.
match mpls-label
no match mpls-label
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Route map configuration
Command History
Usage Guidelines
A route map that includes this command can be used in the following instances:
•
With the neighbor route-map in command to manage inbound route maps in BGP
•
With the redistribute bgp command to redistribute route maps in an IGP
Use the route-map global configuration command, and the match and set route map configuration commands, to define the conditions for redistributing routes from one routing protocol into another. Each route-map command has a list of match and set commands associated with it. The match commands specify the match criteria—the conditions under which redistribution is allowed for the current route-map command. The set commands specify the set actions—the particular redistribution actions to perform if the criteria enforced by the match commands are met. The no route-map command deletes the route map.
The match route-map configuration command has multiple formats. The match commands can be given in any order, and all match commands must "pass" to cause the route to be redistributed according to the set actions given with the set commands. The no forms of the match commands remove the specified match criteria.
When you are passing routes through a route map, a route map can have several parts. Any route that does not match at least one match clause relating to a route-map command will be ignored; that is, the route will not be advertised for outbound route maps and will not be accepted for inbound route maps. If you want to modify only some data, you must configure a second route map section with an explicit match specified.
Examples
The following example creates a route map that redistributes routes if the following conditions are met:
•
The IP address of the route matches an IP address in ACL 2.
•
The route includes an MPLS label.
route-map incoming permit 10match ip address 2match mpls-labelRelated Commands
neighbor send-label
To enable a Border Gateway Protocol (BGP) router to send Multiprotocol Label Switching (MPLS) labels with BGP routes to a neighboring BGP router, use the neighbor send-label command in router configuration mode. To disable the BGP router from sending MPLS labels with BGP routes, use the no form of this command.
neighbor {ip-address} send-label
no neighbor {ip-address} send-label
Syntax Description
Defaults
By default, BGP routers distribute only BGP routes.
Command Modes
Router configuration
Command History
Usage Guidelines
This command enables a router to use BGP to distribute MPLS labels along with the IPv4 routes to a peer router. You must issue this command on both the local router and the neighboring router.
This command has the following restrictions:
•
If a BGP session is running when you issue the neighbor send-label command, the command does not take effect until the BGP session is restarted.
•
You can use this command only with IPv4 addresses.
Cisco IOS installs /32 routes for directly connected external BGP (eBGP) peers when the BGP session for such a peer comes up. The /32 routes are installed only when MPLS labels are exchanged between such peers. Directly connected eBGP peers exchange MPLS labels for:
•
IP address families (IPv4 and IPv6) with the neighbor send-label command enabled for the peers
•
VPN address families (VPNv4 and VPNv6)
A single BGP session can include multiple address families. If one of the families exchanges MPLS labels, the /32 neighbor route is installed for the connected peer.
Examples
The following example enables a router called BGP 1 to send MPLS labels with BGP routes to the neighboring router, whose IP address is 192.168.0.0:
router bgp1neighbor 192.168.0.0 send-labelRelated Commands
Command Descriptionneighbor activate
Enables the exchange of IPv4 address information with a BGP neighboring router.
set mpls-label
To enable a route to be distributed with a Multiprotocol Label Switching (MPLS) label if the route matches the conditions specified in the route map, use the set mpls-label command in route map configuration mode. To disable this function, use the no form of this command.
set mpls-label
no set mpls-label
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Route map configuration
Command History
Usage Guidelines
This command can be used only with the neighbor route-map out command to manage outbound route maps for a Border Gateway Protocol (BGP) session.
Use the route-map global configuration command with match and set route-map configuration commands to define the conditions for redistributing routes from one routing protocol into another. Each route-map command has a list of match and set commands associated with it. The match commands specify the match criteria—the conditions under which redistribution is allowed for the current route-map command. The set commands specify the set actions—the particular redistribution actions to perform if the criteria enforced by the match commands are met. The no route-map command deletes the route map.
Examples
The following example creates a route map that enables the route to be distributed with a label if the IP address of the route matches an IP address in ACL 1.
route-map incoming permit 10match ip address 1set mpls-labelRelated Commands
show ip bgp
To display entries in the Border Gateway Protocol (BGP) routing table, use the show ip bgp command in privileged EXEC mode.
show ip bgp [network] [network-mask] [longer-prefixes]{prefix-list prefix-list-name | route-map route-map-name] [shorter prefixes mask-length]
Syntax Description
Command Modes
Privileged EXEC
Command History
Examples
The following is sample output from the show ip bgp command in privileged EXEC mode:
Router# show ip bgpBGP table version is 5, local router ID is 10.0.33.34Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 1.0.0.0 0.0.0.0 0 32768 ?* 2.0.0.0 10.0.33.35 10 0 35 ?*> 0.0.0.0 0 32768 ?* 10.0.0.0 10.0.33.35 10 0 35 ?*> 0.0.0.0 0 32768 ?*> 192.168.0.0/16 10.0.33.35 10 0 35 ?Table 3 describes the significant fields shown in the display.
The following is sample output from the show ip bgp command in privileged EXEC mode when you specify the longer-prefixes keyword:
Router# show ip bgp 198.92.0.0 255.255.0.0 longer-prefixesBGP table version is 1738, local router ID is 198.92.72.24Status codes: s suppressed, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 198.92.0.0 198.92.72.30 8896 32768 ?* 198.92.72.30 0 109 108 ?*> 198.92.1.0 198.92.72.30 8796 32768 ?* 198.92.72.30 0 109 108 ?*> 198.92.11.0 198.92.72.30 42482 32768 ?* 198.92.72.30 0 109 108 ?*> 198.92.14.0 198.92.72.30 8796 32768 ?* 198.92.72.30 0 109 108 ?*> 198.92.15.0 198.92.72.30 8696 32768 ?* 198.92.72.30 0 109 108 ?*> 198.92.16.0 198.92.72.30 1400 32768 ?* 198.92.72.30 0 109 108 ?*> 198.92.17.0 198.92.72.30 1400 32768 ?* 198.92.72.30 0 109 108 ?*> 198.92.18.0 198.92.72.30 8876 32768 ?* 198.92.72.30 0 109 108 ?*> 198.92.19.0 198.92.72.30 8876 32768 ?* 198.92.72.30 0 109 108 ?The following is sample output from the show ip bgp command in privileged EXEC mode, showing information for prefix ww.0.0.0:
Router# show ip bgp ww.0.0.0BGP routing table entry for ww.0.0.0/8, version 628Paths: (1 available, best #1)Advertised to peer-groups:ebgpAdvertised to non peer-group peers:171.69.232.162109 65000 297 701 80171.69.233.56 from 171.69.233.56 (172.19.185.32)Origin incomplete, localpref 100, valid, external, best, ref 2MPLS labels in/out 24/22
Note
If a prefix has not been advertised to any peer, the display shows "Not advertised to any peer."
The following is sample output from the show ip bgp command in privileged EXEC mode when you specify the prefix-list keyword:
Router# show ip bgp prefix-list ROUTEBGP table version is 39, local router ID is 10.0.0.1Status codes:s suppressed, d damped, h history, * valid, > best, i -internalOrigin codes:i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 192.168.1.0 10.0.0.2 0 ?* 10.0.0.2 0 0 200 ?The following is sample output from the show ip bgp command in privileged EXEC mode when you specify the route-map keyword:
Router# show ip bgp route-map LEARNED_PATHBGP table version is 40, local router ID is 10.0.0.1Status codes:s suppressed, d damped, h history, * valid, > best, i -internalOrigin codes:i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 192.168.1.0 10.0.0.2 0 ?* 10.0.0.2 0 0 200 ?The following is sample output from the show ip bgp command in privileged EXEC mode when you specify the shorter-prefixes keyword:
Router# show ip bgp 172.16.0.0/16 shorter-prefixes 8*> 172.16.0.0 10.0.0.2 0 ?* 10.0.0.2 0 0 200 ?Related Commands
Command Descriptionclear ip bgp
Resets a BGP connection or session.
neighbor soft-reconfiguration
Configures the Cisco IOS software to start storing updates.
show ip bgp labels
To display information about Multiprotocol Label Switching (MPLS) labels from the External Border Gateway Protocol (EBGP) route table, use the show ip bgp labels command in privileged EXEC mode.
show ip bgp labels
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Use this command to display EBGP labels associated with a carrier supporting carrier customer edge (CSC-CE) router.
This command displays labels for BGP routes in the default table only. To display labels in the VRF tables, use the show ip bgp vpnv4 {all | vrf vrf-name} command with the optional labels keyword.
Examples
The following example shows output for a CSC-CE router using BGP as a label distribution protocol:
Router# show ip bgp labelsNetwork Next Hop In Label/Out Label3.3.0.0/16 0.0.0.0 imp-null/exp-null15.15.15.15/32 15.15.15.15 18/exp-null16.16.16.16/32 0.0.0.0 imp-null/exp-null17.17.17.17/32 34.0.0.1 20/exp-null18.18.18.18/32 43.0.0.1 24/3118.18.18.18/32 38.0.0.1 24/3319.19.19.19/32 43.0.0.1 25/3219.19.19.19/32 38.0.0.1 25/3420.20.20.20/32 43.0.0.1 21/3020.20.20.20/32 38.0.0.1 21/3233.0.0.0 15.15.15.15 19/exp-null34.0.0.0 0.0.0.0 imp-null/exp-null35.0.0.0 43.0.0.1 22/2935.0.0.0 38.0.0.1 22/3138.0.0.0 0.0.0.0 imp-null/exp-null38.0.0.1/32 38.0.0.1 17/2938.0.0.1/32 0.0.0.0 17/exp-null40.0.0.0 38.0.0.1 26/3540.0.0.0 43.0.0.1 26/3442.0.0.0 43.0.0.1 23/2842.0.0.0 38.0.0.1 23/3043.0.0.0 0.0.0.0 imp-null/exp-null43.0.0.1/32 0.0.0.0 16/exp-nullTable 4 describes the significant fields shown in the display.
Related Commands
show ip bgp neighbors
To display information about the TCP/IP and Border Gateway Protocol (BGP) connections to neighbors, use the show ip bgp neighbors command in EXEC mode.
show ip bgp neighbors [neighbor-address] [received-routes | routes | advertised-routes | {paths regexp} | dampened-routes] [received prefix-filter]
Syntax Description
Command Modes
EXEC
Command History
Examples
The following example shows output from the show ip bgp neighbors command in privileged EXEC mode when Multiprotocol Label Switching (MPLS) labels are being sent and received:
Router# show ip bgp neighbors 172.16.232.178BGP neighbor is 172.16.232.178, remote AS 35, external linkBGP version 4, remote router ID 192.168.3.3BGP state = Established, up for 1w1dLast read 00:00:53, hold time is 180, keepalive interval is 60 secondsNeighbor capabilities:MPLS Label capability: advertised and receivedAddress family IPv4 Unicast: advertised and receivedAddress family IPv4 Multicast: advertised and receivedReceived 12519 messages, 0 notifications, 0 in queueSent 12523 messages, 0 notifications, 0 in queueRoute refresh request: received 0, sent 0Minimum time between advertisement runs is 30 secondsFor address family: IPv4 UnicastBGP table version 5, neighbor version 5Index 1, Offset 0, Mask 0x2Community attribute sent to this neighborInbound path policy configuredOutbound path policy configuredRoute map for incoming advertisements is uni-inRoute map for outgoing advertisements is uni-outSending Prefix & Label3 accepted prefixes consume 108 bytesPrefix advertised 6, suppressed 0, withdrawn 0For address family: IPv4 MulticastBGP table version 5, neighbor version 5Index 1, Offset 0, Mask 0x2Inbound path policy configuredOutbound path policy configuredRoute map for incoming advertisements is mul-inRoute map for outgoing advertisements is mul-out3 accepted prefixes consume 108 bytesPrefix advertised 6, suppressed 0, withdrawn 0Connections established 2; dropped 1Last reset 1w1d, due to Peer closed the sessionConnection state is ESTAB, I/O status: 1, unread input bytes: 0Local host: 172.16.232.178, Local port: 179Foreign host: 172.16.232.179, Foreign port: 11002Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes)Event Timers (current time is 0x2CF49CF8):Timer Starts Wakeups NextRetrans 12518 0 0x0TimeWait 0 0 0x0AckHold 12514 12281 0x0SendWnd 0 0 0x0KeepAlive 0 0 0x0GiveUp 0 0 0x0PmtuAger 0 0 0x0DeadWait 0 0 0x0iss: 273358651 snduna: 273596614 sndnxt: 273596614 sndwnd: 15434irs: 190480283 rcvnxt: 190718186 rcvwnd: 15491 delrcvwnd: 893SRTT: 300 ms, RTTO: 607 ms, RTV: 3 ms, KRTT: 0 msminRTT: 0 ms, maxRTT: 300 ms, ACK hold: 200 msFlags: passive open, nagle, gen tcbsDatagrams (max data segment is 1460 bytes):Rcvd: 24889 (out of order: 0), with data: 12515, total data bytes: 237921Sent: 24963 (retransmit: 0), with data: 12518, total data bytes: 237981Table 5 describes the significant fields shown in the display.
The following is sample output from the show ip bgp neighbors command with the advertised-routes keyword in privileged EXEC mode:
Router# show ip bgp neighbors 172.16.232.178 advertised-routesBGP table version is 27, local router ID is 172.16.232.181Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*>i110.0.0.0 172.16.232.179 0 100 0 ?*> 200.2.2.0 0.0.0.0 0 32768 iThe following is sample output from the show ip bgp neighbors command with the routes keyword in privileged EXEC mode:
Router# show ip bgp neighbors 172.16.232.178 routesBGP table version is 27, local router ID is 172.16.232.181Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 10.0.0.0 172.16.232.178 40 0 10 ?*> gg.0.0.0 172.16.232.178 40 0 10 ?Table 6 describes the significant fields shown in the displays.
The following is sample output from the show ip bgp neighbors command with the paths keyword in privileged EXEC mode:
Router# show ip bgp neighbors 171.69.232.178 paths ^10Address Refcount Metric Path0x60E577B0 2 40 10 ?Table 7 describes the significant fields shown in the display.
The following is sample output from the show ip bgp neighbors command with the received prefix-filter keyword in privileged EXEC mode:
Router# show ip bgp neighbor 192.168.20.72 received prefix-filterAddress family:IPv4 Unicastip prefix-list 192.168.20.72:1 entriesseq 5 deny 10.0.0.0/8 le 32Table 8 describes the significant fields shown in the display.
show ip bgp vpnv4
To display Virtual Private Network (VPN) address information from the Border Gateway Protocol (BGP) table, use the show ip bgp vpnv4 command in EXEC mode.
show ip bgp vpnv4 {all | rd route-distinguisher | vrf vrf-name} [ip-prefix/length [longer-prefixes] [output-modifiers]] [network-address [mask] [longer-prefixes] [output-modifiers]] [cidr-only] [community] [community-list] [dampened-paths] [filter-list] [flap-statistics] [inconsistent-as] [neighbors] [paths [line]] [peer-group] [quote-regexp] [regexp] [summary] [labels]
Syntax Description
Defaults
This command has no default behavior or values.
Command Modes
EXEC
Command History
Usage Guidelines
Use this command to display VPNv4 information from the BGP database. The show ip bgp vpnv4 all command displays all available VPNv4 information. The show ip bgp vpnv4 summary command displays BGP neighbor status.
Examples
The following example shows output for all available VPNv4 information in a BGP routing table:
Router# show ip bgp vpnv4 allBGP table version is 18, local router ID is 14.14.14.14Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP,? - incompleteNetwork Next Hop Metric LocPrf Weight PathRoute Distinguisher: 1:101 (default for vrf vpn1)*>i6.6.6.6/32 223.0.0.21 11 100 0 ?*> 7.7.7.7/32 150.150.0.2 11 32768 ?*>i69.69.0.0/30 223.0.0.21 0 100 0 ?*> 150.150.0.0/24 0.0.0.0 0 32768 ?*> 222.0.0.1/32 150.150.0.2 11 32768 ?*>i222.0.0.3/32 223.0.0.21 11 100 0 ?*> 222.0.0.10/32 0.0.0.0 0 32768 ?*>i222.0.0.30/32 223.0.0.21 0 100 0 ?Table 9 describes the significant fields shown in the display.
The following example shows how to display a table of labels for NLRIs that have a route distinguisher value of 100:1.
Router# show ip bgp vpnv4 rd 100:1 labelsNetwork Next Hop In label/Out labelRoute Distinguisher: 100:1 (vrf1)2.0.0.0 10.20.0.60 34/nolabel10.0.0.0 10.20.0.60 35/nolabel12.0.0.0 10.20.0.60 26/nolabel10.20.0.60 26/nolabel13.0.0.0 10.15.0.15 nolabel/26Table 10 describes the significant fields shown in the display.
The following example shows VPNv4 routing entries for the VRF named vpn1:
Router# show ip bgp vpnv4 vrf vpn1BGP table version is 18, local router ID is 14.14.14.14Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP,? - incompleteNetwork Next Hop Metric LocPrf Weight PathRoute Distinguisher: 1:101 (default for vrf vpn1)*>i6.6.6.6/32 223.0.0.21 11 100 0 ?*> 7.7.7.7/32 150.150.0.2 11 32768 ?*>i69.69.0.0/30 223.0.0.21 0 100 0 ?*> 150.150.0.0/24 0.0.0.0 0 32768 ?*> 222.0.0.1/32 150.150.0.2 11 32768 ?*>i222.0.0.3/32 223.0.0.21 11 100 0 ?Table 11 describes the significant fields shown in the display.
The following example shows attributes for network 10.22.22.0 that includes multipaths and a best path:
Router# show ip bgp vpnv4 all 10.22.22.0BGP routing table entry for 100:1:10.22.22.0/24, version 50Paths:(6 available, best #1)Multipath:iBGPAdvertised to non peer-group peers:200.1.12.12221.22.7.8 (metric 11) from 1.11.3.4 (100.0.0.8)Origin IGP, metric 0, localpref 100, valid, internal, multipath, bestExtended Community:RT:100:1Originator:100.0.0.8, Cluster list:100.1.1.44221.22.1.9 (metric 11) from 1.11.1.2 (100.0.0.9)Origin IGP, metric 0, localpref 100, valid, internal, multipathExtended Community:RT:100:1Originator:100.0.0.9, Cluster list:100.1.1.22221.22.6.10 (metric 11) from 1.11.6.7 (100.0.0.10)Origin IGP, metric 0, localpref 100, valid, internal, multipathExtended Community:RT:100:1Originator:100.0.0.10, Cluster list:100.0.0.7221.22.4.10 (metric 11) from 1.11.4.5 (100.0.0.10)Origin IGP, metric 0, localpref 100, valid, internal, multipathExtended Community:RT:100:1Originator:100.0.0.10, Cluster list:100.0.0.5221.22.5.10 (metric 11) from 1.11.5.6 (100.0.0.10)Origin IGP, metric 0, localpref 100, valid, internal, multipathExtended Community:RT:100:1Originator:100.0.0.10, Cluster list:100.0.0.6Table 12 describes the significant fields shown in the display.
Related Commands
show route-map
To display all route maps configured or only the one specified, use the show route-map command in EXEC mode.
show route-map [map-name]
Syntax Description
Command Modes
EXEC
Command History
Examples
The following is sample output from the show route-map command:
Router# show route-maproute-map sid, permit, sequence 10Match clauses:tag 1 2Set clauses:metric 5route-map sid, permit, sequence 20Match clauses:tag 3 4Set clauses:metric 6Policy routing matches: 0packets; 0 bytesThe following example shows MPLS-related route map information:
Router# show route-maproute-map OUT, permit, sequence 10Match clauses:ip address (access-lists): 1Set clauses:mpls labelPolicy routing matches: 0 packets, 0 bytesroute-map IN, permit, sequence 10Match clauses:ip address (access-lists): 2mpls labelSet clauses:Policy routing matches: 0 packets, 0 bytesTable 13 describes the fields shown in the display.
Related Commands
Glossary
autonomous system (AS)—A collection of networks that share the same routing protocol and that are under the same system administration.
Border Gateway Protocol (BGP)—The exterior border gateway protocol used to exchange routing information between routers in separate autonomous systems. BGP uses Transmission Control Protocol (TCP). Because TCP is a reliable protocol, BGP does not experience problems with dropped or fragmented data packets.
BGP prefixes—A route announcement using the BGP. A prefix is composed of a path of AS numbers, indicating which networks the packet must pass through, and the IP block that is being routed. A BGP prefix would look something like: 701 1239 42 206.24.14.0/24. (The /24 part is referred to as a CIDR mask. The /24 indicates that there are 24 ones in the netmask for this block starting from the left hand side. A /24 corresponds to the natural mask 255.255.255.0.
customer edge (CE) router—The customer router that connects to the provider edge (PE) router.
External Border Gateway Protocol (EBGP)—A BGP session between routers in different autonomous systems. When a pair of routers in different ASs are more than one IP hop away from each other, an external BGP session between those two routers is called multihop external BGP.
Internal Border Gateway Protocol (IBGP)—A BGP session between routers within the same autonomous system.
Label Distribution Protocol (LDP)—A standard protocol used by MPLS-enabled routers to assign the labels (addresses) used to forward packets.
label edge router (LER)—The edge router that performs label imposition and disposition.
label-switched path (LSP)—A sequence of hops in which a packet travels from one router to another router by means of label switching mechanisms. A label-switched path can be established dynamically, based on normal routing mechanisms, or through configuration.
label switch router (LSR)—An LSR forwards packets in an MPLS network by looking only at the fixed-length label.
Multiprotocol Label Switching (MPLS)—MPLS is a method for forwarding packets (frames) through a network. It enables routers at the edge of a network to apply labels to packets (frames). ATM switches or existing routers in the network core can switch packets according to the labels.
Multihop BGP—A Border Gateway Protocol between two routers in different autonomous systems that are more than one hop away from each other.
Network Layer Reachability Information (NLRI)—BGP sends routing update messages containing NLRI, which describes the route. In this context, an NLRI is a prefix. A BGP update message carries one or more NLRI prefixes and the attributes of a route for the NLRI prefixes. The route attributes include a BGP next hop gateway address, community values, and other information.
point of presence (POP)—An access point to the Internet. A POP has a unique IP address. The ISP or online service provider (such as AOL) has one or more POPs on the Internet. ISP users dial into the POP to connect to the Internet. A POP can reside in rented space owned by the telecommunications carrier (such as Sprint) to which the ISP is connected. A POP usually includes routers, digital/analog call aggregators, servers, and frequently frame relay or ATM switches.
provider edge (PE) router—The label edge router (LER) in the service provider network that connects to the customer edge (CE) router.
route reflector (RR)—A router that advertises, or reflects, IBGP learned routes to other IBGP peers without requiring a full network mesh.
Virtual Private Network (VPN)—A group of sites that, as a result of a set of administrative policies, can communicate with each other over a shared backbone.
VPNv4 addresses—When multiple VPNs use the same address space, the VPN addresses are made unique by adding a route distinguisher to the front of the address.
VPN routing/forwarding table (VRF table)—A VRF table includes the routing information that defines a customer VPN site that is attached to a PE router. A VRF table consists of the following elements:
•
An IP routing table
•
A derived forwarding table
•
A set of interfaces that use the forwarding table
•
A set of rules and routing protocols that determine what goes into the forwarding table
Feedback



