Failure Scenarios
This chapter provides details of all failure scenarios reported by the Cisco Prime Diagnostics application. It also details IOS XR support caveats.
For more information, e-mail: mpls-diagnostics-expert@cisco.com
Note Prime Diagnostics only supports L3 services implemented on sub-interfaces/interfaces.
Failure Scenarios
This section lists the failure scenarios reported by Diagnostics, as follows:
•Access Circuit
•MPLS Edge
•MPLS Core
•Customer Site
Each failure scenario provides a table that lists whether the failure scenario is supported by each of the five Diagnostics test types. This table details whether the failure scenario is supported on IOS and IOS XR. The table also details if the failure scenario is supported for IPv4 and IPv6.
Note In the following tables, NA stands for Not Applicable and NS stands for Not Supported.
Access Circuit
Access Circuit Blocking IP Connectivity
There is a blocking access list preventing IP connectivity from an access circuit interface on the provider (PE) router to the destination.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
An Invalid PE Interface has been Specified
Interface does not exist on the PE router.
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Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
ATM Interface Has No VPI/VCI
An asynchronous transfer mode (ATM) access circuit interface on a PE router has no virtual path identifier (VPI), or virtual channel identifier (VCI) assigned to it, or no VPI/VCI maps to the destination IP address.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
ATM Interface Is Protocol Down
An ATM access circuit interface on a PE router is protocol down. See the "IOS XR Support" section.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
ATM Sub-interface is Protocol Down
An ATM access circuit subinterface on a PE router is protocol down. This might be caused by incorrect subinterface parameters or by ATM Operation, Administration, and Maintenance (OAM) detecting a fault and bringing the interface down automatically. See the "IOS XR Support" section.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Calculation of the CE Access Circuit Interface IP Address is only possible if the PE interface is not Unnumbered and has a /30 Subnet mask Interface on PE
Unable to calculate the customer edge (CE) access circuit interface IP address for the PE.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NA |
For more details see the "IPv6 Support" section.
eBGP Max Prefix Exceeded for Peer
Exterior border gateway protocol (eBGP) is running between the PE and CE, however the border gateway protocol (BGP) neighbor is not established. The peer has exceeded the configured maximum number of prefixes.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
eBGP Neighbor Not Established, No Route Present
eBGP is running between the PE and CE, but the BGP neighbor on the PE is not established. The BGP neighbor is on a different subnet from the PE and there is no route to the neighbor in the VPN routing/forwarding (VRF).
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
eBGP Neighbor Not Established, Possible Misconfiguration
eBGP is running between the PE and CE, but the BGP neighbor on the PE is not established. There is a route to the BGP neighbor in the VRF and it is reachable via ping. Possible CE or PE BGP configuration problem.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
eBGP Neighbor Not Established, Route Present
eBGP is running between the PE and CE, but the BGP neighbor on the PE is not established. The BGP neighbor is on a different subnet from the PE and there is a route to the neighbor in the VRF. However, the BGP neighbor is unreachable via ping.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
eBGP sites use the same AS number
The local and remote sites use eBGP and share the same AS number and neither "allowas-in" nor "as-override" is configured for the BGP neighbor within the vrf on the local PE router.
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Yes |
NA |
NA |
NA |
NA |
NA |
Yes |
Yes |
Yes |
EIGRP Not Exchanging Routes
The enhanced interior gateway routing protocol (EIGRP) is running between the PE and CE and a peer relationship has been established. However, no routes have been received from EIGRP on the CE.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Ethernet Interface Protocol Down
An Ethernet access circuit interface on the PE router protocol is down.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Ethernet Sub-Interface Protocol Down
An Ethernet access circuit subinterface on the PE router protocol is down.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Frame Relay Interface Has No DLCI
A Frame Relay access circuit interface on the PE router has no data-link connection identifier (DLCI) assigned to it, or no DLCI maps to the destination IP address.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Frame Relay Interface Protocol Down
A Frame Relay access circuit interface on the PE router protocol is down. This might be because of line parameters or cabling faults.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Frame Relay Interface Has No DLCI
A multipoint Frame Relay permanent virtual circuit (PVC) on an access circuit interface on the PE router has no DLCI that maps to the destination IP address.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Frame Relay Interface Has No DLCI
A point-to-point Frame Relay PVC on an access circuit interface on the PE router has no DLCI assigned to it.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Frame Relay PVC Marked as Deleted
A Frame Relay PVC on an access circuit interface on the PE router is marked as deleted.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
NA |
Yes |
NS |
Frame Relay PVC Marked as Down
A multipoint Frame Relay PVC on an access circuit interface on the PE router is marked as down.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
NA |
Yes |
NS |
Frame Relay PVC Marked as Down
A point-to-point Frame Relay PVC on an access circuit interface on the PE router is marked as down.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Incomplete Carrier on Serial Interface
A serial access circuit interface on the PE router has an incomplete carrier.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Interface Administratively Down
An access circuit interface (or subinterface) on the PE router is administratively down.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Interface Administratively Down
An access circuit subinterface on the PE router is administratively down.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Interface in Protocol Down State
An access circuit interface on the PE router protocol is down.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Interface on the PE is a Bundle Link Virtual-Access Interface
The interface on the PE is not a valid access circuit interface.
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Yes |
Yes |
Yes |
Yes |
NA |
Yes |
NA |
Yes |
NS |
Interface Operationally Down
An access circuit interface on the PE router is operationally down.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Intermittent ATM Failure (to the ATM Next Hop)
An ATM access circuit has intermittent ATM access to the ATM next hop. See the "IOS XR Support" section.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Intermittent ATM Failure (to the Destination)
An ATM access circuit has intermittent ATM access to the destination. See the "IOS XR Support" section.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Invalid Access Circuit IP Address Configuration
The CE router access circuit interface IP address is not in the same subnet as the attached PE access circuit interface IP address.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Invalid Access Circuit IP Address Configuration
The CE access circuit interface IP address is a network address.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NA |
For more details see the "IPv6 Support" section.
Invalid Access Circuit IP Address Configuration
The CE access circuit interface IP address is a network broadcast address.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NA |
For more details see the "IPv6 Support" section.
Invalid Access Circuit IP Address Configuration
The CE access circuit interface IP address is the same as the attached PE access circuit interface IP address.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
IP Connectivity Problem
Unknown IP connectivity issue. An access circuit connectivity problem in the VRF instance from the PE interface to the CE.
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NA |
Yes |
NA |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Missing Route
There is no route from the access circuit interface on the PE router to the destination.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Missing Route
There is no route from the access circuit interface on the PE router to the customer destination.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
No EIGRP Peer Relationship Established
The routing protocol EIGRP is running between the PE and CE, however no peer relationship has been established.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
No EIGRP Peer Relationship Established
The routing protocol EIGRP is running between the PE and CE. The PE and CE interfaces are on different subnets and are not using IP unnumbered. No peer relationship has been established as the PE and CE are on different subnets.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Route redistribution does not specify a route-policy
The routing protocol EIGRP is running between the PE and CE and is redistributing routes into MP-BGP. However no outbound route policy has been specified, which means all routes will be dropped rather than advertised.
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Yes |
Yes |
Yes |
NA |
NA |
NA |
Yes |
Yes |
NS |
No OSPF Peers
Open shortest path first (OSPF) is running between the PE and CE, but no peer exists on the PE.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
OSPF not enabled on peer interface
The interface on the router does not have OPSF enabled. OSPF must be enabled on both neighboring interface.
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Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
NS |
OSPF in passive mode on peer interface
OSPF on interface on the router is in passive mode.
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Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
NS |
OSPF Area Mismatch
OSPF is enabled on the neighboring interfaces; however the interfaces are configured in different areas.
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Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
NS |
OSPF Area Type Mismatch
OSPF is enabled on the neighboring interfaces; however the interfaces are configured as different area types.
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Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
NS |
No Routing Protocol has been Determined Running between the PE and CE and no Static Route is Present
An access circuit connectivity problem in VRF.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
OSPF Not Exchanging Routes
OSPF is running between the PE and CE, but a peer relationship has been established. However, no routes have been received from OSPF on the CE.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
OSPF Peers Not Established
OSPF is running between the PE and CE, but a peer relationship has not been established.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NA |
OSPF Timer Mismatch
OSPF is enabled on the neighboring interfaces; however the interfaces have different values configured for their [hello|dead] timers.
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Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
NS |
OSPF Peers Not Established
OSPF is running between the PE and CE. However, a peer relationship has not been established as PE and CE interfaces are on different subnets and are not using IP unnumbered.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Route redistribution does not specify a route-policy
The routing protocol OSPF is running between the PE and CE and is redistributing routes into MP-BGP. However no outbound route policy has been specified, which means all routes will be dropped rather than advertised.
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Yes |
Yes |
Yes |
NA |
NA |
NS |
Yes |
Yes |
NS |
PE has No Route to CE
Connected PE and CE interfaces are on different subnets. No routing protocol has been determined running between the PE and CE and no static route to the CE is present.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
NA |
Yes |
NS |
RIB Failure
A route from the PE to a destination in a VRF has not been installed in the VRF routing table. This has been identified as a Routing Information Base (RIB) failure.
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Yes |
Yes |
Yes |
Yes |
NA |
Yes |
NA |
Yes |
NS |
RIP Misconfiguration
Routing information protocol (RIP) is running between the PE and CE, but no routes have been received from RIP on the CE.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
RIP Not Exchanging Routes
RIP is running between the PE and CE, but no routes have been received from RIP on the CE as the PE and CE interfaces are on different subnets and are not using IP unnumbered.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Route redistribution does not specify a route-policy
The routing protocol RIP is running between the PE and CE and is redistributing routes into MP-BGP. However no outbound route policy has been specified, which means all routes will be dropped rather than advertised.
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Yes |
Yes |
Yes |
NA |
NA |
NA |
Yes |
Yes |
NS |
Serial Interface in Loopback Mode
A serial access circuit interface on the PE router is configured in loopback mode.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Serial Interface Operationally Down
A serial access circuit interface on the PE router is operationally down.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Static IP address on ATM Point-to-Point Interface
An ATM access circuit has a static IP address mapping on an ATM point-to-point subinterface. Neither a static mapping nor an address resolution protocol (ARP) are required on a point-to-point subinterface because there is a single VC and a single path for the traffic. See the "IOS XR Support" section.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Sub-interface in Protocol Down State
An access circuit subinterface on the PE router protocol is down.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Undiagnosed ATM Failure (ATM Pings Failed but the ATM Segment Ping Succeeded)
An ATM access circuit connection is broken. The end-to-end ATM ping failed, but the ATM segment ping succeeded. This might be caused by various issues such as incorrect ATM line parameters, misconfigured ATM routing, CE or ATM cloud interfaces being down, or devices being down. See the "IOS XR Support" section.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Undiagnosed ATM Failure (End to End and Segment ATM Pings Failed)
An ATM access circuit connection is broken. Both the end-to-end and segment ATM pings failed. This might be caused by various issues such as incorrect ATM line parameters, misconfigured ATM routing on the ATM next hop, next hop interfaces being down, or devices being down. See the IOS XR Support.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Virtual Template Interface has been Specified for the PE Access Circuit Interface
The PE interface on the PE is not a valid access circuit interface.
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Yes |
Yes |
Yes |
Yes |
NA |
Yes |
NA |
Yes |
NS |
MPLS Edge
BGP Next Hop Interface Admin Down
BGP next hop on PE is assigned to a loopback interface. However, that interface is administratively down.
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Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
BGP Next Hop is Not Assigned to an Interface
The BGP next hop for routes to the remote site PE is not assigned to an interface on the remote PE.
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Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
BGP Not Active
BGP is not active on the PE router.
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Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
BGP Peers Using Same BGP Next Hop
BGP VPNv4/VPNv6 peers use the same BGP next hop. This prevents correct route distribution of PE routes. Other routing problems might also be encountered.
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Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
BGP Peers Using Same Router Identifier (RID)
BGP VPNv4/VPNv6 peers use the same router identifier. This prevents correct route distribution of PE routes. Other routing problems might also be encountered.
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Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Multiple Access Circuits in the same subnet
LSP Connectivity problem, control plane issue. The next-hop for the current BGP selected route(s) to the remote PE router is not assigned to an interface on the local PE router. There are multiple VPNv4/VPNv6 routes found within the vrf on the locale PE router to the remote prefix.
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Yes |
NA |
NA |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
BGP to LFIB Mismatch
Untagged entry has mismatch between BGP and label forwarding information base (LFIB) tables.
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Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
BGP to LFIB Mismatch
The forwarding information base (FIB) and BGP entries are inconsistent.
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Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Duplicate BGP Next Hop
Duplicate IP address found in the network for the BGP next hop on PE.
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Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Duplicate IP Address
There is a duplicate IP address configured on the PE router that conflicts with an access circuit interface.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Duplicate IP Address
Duplicate IP address found in the network for the BGP router identifier on PE.
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Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
eBGP not Redistributing Connected Routes into MP-BGP
The routing protocol eBGP is running between the PE and CE, but eBGP on the PE is not redistributing connected routes into Multi Protocol (MP)-BGP, also there is no explicit network statement.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
FIB to LFIB Mismatch
Aggregate entry has mismatch between FIB and LFIB tables.
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Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Ingress FIB to Egress LFIB Mismatch
Egress LFIB and Ingress FIB inconsistency.
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Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Inconsistent BGP Entries
BGP entries are inconsistent for the VRF.
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|
|
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Label mismatch or interfaces on different VPNs Down
VPN connectivity problem in VRF from PE to destination. BGP VPNv4/VPNv6 label for prefix do not match. This might indicate a label mismatch or interfaces on different VPNs. Check that the interfaces selected are on the same VRF.
|
|
|
|
|
|
|
|
|
NA |
NA |
NA |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
PE interface is administratively down
The access circuit interface on the PE router is administratively down.
|
|
|
|
|
|
|
|
|
Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
NS |
Missing Router Identifier (RID)
Unable to determine the local router identifier on the PE.
|
|
|
|
|
|
|
|
|
NA |
NA |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Missing VPNv4 Address Family Configuration
VPNv4 configuration missing; Virtual private network (VPN) label exchange problem. VPNv4 address family configuration missing from BGP router configuration on the PE router. This results in routes being dropped.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Missing VPNv6 Address Family Configuration
VPNv6 configuration missing; Virtual private network (VPN) label exchange problem. VPNv6 address family configuration missing from BGP router configuration on the PE router. This results in routes being dropped.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
NA |
Yes |
NA |
Yes |
MPLS LDP Package not enabled on IOS XR Router
The MPLS LDP package is not enabled on the IOS XR router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
MPLS Package installed but not active on IOS XR Router
The MPLS package is installed, but it is not active on the IOS XR router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
MPLS Package not installed on IOS XR Router
The MPLS package is not installed on the IOS XR router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
No MP-BGP Neighbors
There are no MP-BGP neighbors defined on the PE router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
No MP-BGP Neighbor Session Established
No MP-BGP neighbor session established on the PE router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
No VPN Label For Prefix
No VPN label has been allocated for the prefix.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
No VRF Associated with PE Interface
An interface on the PE router has no VRF associated.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
OSPF Loopback Interface Uses A Non /32 Netmask
VPNv4 routes are being advertised to IBGP neighbors by the PE. The address of the next hop is a loopback interface that does not have a /32 mask defined. OSPF is being used on this loopback interface, and the OSPF network type of this interface is loopback. OSPF advertises this IP address as a host route (with mask /32), regardless of what mask is configured. This advertising conflicts with TDP/LDP, that uses configured masks, so the TDP/LDP neighbors might not receive a label for the routes advertised by this router. This condition could break connectivity between sites that belong to the same VPN.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
NA |
PE Interface Has No IP Address
An interface on the PE router has no IP address.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Router ID Loopback Interface Down
The loopback interface used to assign the local router ID on the PE is administratively down.
|
|
|
|
|
|
|
|
|
Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Routes not Redistributed to or from MP-BGP
Routes are not being redistributed to or from MP-BGP on the PE.
|
|
|
|
|
|
|
|
|
Yes |
Yes |
Yes |
NA |
NA |
Yes |
NA |
Yes |
NA |
Static Route to Remote Prefix
A static route to a remote prefix has been configured within a VRF on the PE.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Traffic Administratively Blocked
VPN connectivity problem from the PE to the destination due to traffic being administratively blocked.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
Troubleshooting of the Layer 3 VPN has been Unable to Find the Cause of the Failure
LSP connectivity problem.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Troubleshooting of the Layer 3 VPN has been Unable to Find the Cause of the Failure
VPN connectivity problem in VRF from PE to destination.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
VRF Route Target Import/Export Mismatch
VRF route target import/export mismatch between the PE devices.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
MPLS Core
An Invalid PE Interface has been Specified
Interface supplied as the LSP Endpoint does not exist on the PE router.
|
|
|
|
|
|
|
|
|
NA |
NA |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Broken LDP Neighbor Session
LDP session with downstream neighbor broken. Route processor/line card forwarding discrepancy on the router. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
CEF Not Enabled On Router
CEF has not been enabled on a router. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Distributed LFIB Table Discrepancy
There is a discrepancy in the LFIB table between the route processor and line cards.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Distributed FIB Table Discrepancy
There is a discrepancy in the FIB table between the route processor and line cards.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Label Inconsistency
LFIB local tag, received packet, and LDP local binding label inconsistent on the router. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
LDP Host Not Reachable
The host is not reachable from the label switch router (LSR). This could be caused by no LDP session on router for the downstream router, LDP ID not reachable because of IGP problem, ACL configured that is blocking LDP packets, or an authentication problem.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
LDP Label Mismatch
Label received for a prefix did not match the label sent. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
LDP Neighbors Not Discovered
LDP neighbors have not been discovered. Generic LDP discovery problem found on an interface of the device with its downstream neighbor. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
LDP Neighbors Not Discovered
LDP neighbors have not been discovered. An interface on a router has an ACL configured that could be preventing LDP neighbor discovery.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
LDP Neighbors Not Established
LSP connectivity problem, control plane issue. The LDP session is not established. The interface has an ACL configured that could be blocking LDP session establishment on port 646.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
LDP/TDP Mismatch
LDP and TDP have been enabled on opposite ends of a link. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
LSP Reply Path Problem
LSP connectivity problem with the reply path. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Missing LFIB Entry
LFIB entry missing. Could be because of misrouting in an earlier router, or due to duplicate loopbacks. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Missing or Untagged Return Path
Return path from the core router absent or untagged for the prefix. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
MPLS Label Space Exhausted
MPLS label space exhausted on a router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
MPLS Not Enabled Globally
MPLS has not been enabled globally on router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
MPLS Not Enabled On Interface
MPLS has not been enabled on an interface. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
No Entry for Label
No entry in LFIB for incoming label going to the destination prefix. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
No LDP Session with Neighbor
No LDP session on router exists with neighbor.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
No Valid Next-Hop Entry
No valid entry can be found for the next-hop from the current device. See the "IOS XR Support" section.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Routing Loop In Forwarding Path
A routing loop is present in the forwarding path.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
All MPLS enabled core facing interfaces are down
LSP connectivity problem, control plane issue. No MPLS enabled interface is operationally up.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Label Advertising Not Enabled
Label advertisement is disabled on router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Label Advertising Possibly Denied by ACL
Label advertisement has been globally disabled, but selectively enabled for one or more access lists. The ACL(s) might be denying the advertising of labels to the destination prefix.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
TTL Propagation Disabled
Could not troubleshoot or detect failure point because the device is not propagating the Time To Live (TTL).
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Check tunnel traffic admission policy
No traffic admission policy (such as via autoroute announce, or Policy Based Tunnel Selection (PBTS) or a static route) configured on the TE Tunnel.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Check if MPLS is enabled on the tunnel interface
Incomplete configuration detected for the MPLS TE Tunnel interface.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
NA |
Yes |
NS |
Yes |
Yes |
Yes |
Check that the primary and backup tunnel's interfaces are up
The tunnel interface on the router is administratively down.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
Tunnel config not present at headend
The TE Tunnel configuration is not present at the headend router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
Check that the tunnels outgoing interface is operational
The outgoing interface of FRR primary tunnel configured on the router is operationally down.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
TE not enabled globally on router
MPLS Traffic Engineering is not enabled globally on the router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
TE not enabled globally on the interface
MPLS Traffic Engineering is not enabled on the interface of the router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
No IP Address assigned for tunnel
MPLS Traffic Engineering Tunnel has no IP address assigned.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
Tunnel destination invalid
The destination address configured for the tunnel is unreachable.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
Tunnel is administratively shut down
Tunnel has been admin shut down on the router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
Missing OSPF configuration for TE
Router has not configured OSPF for MPLS TE.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
Node is not advertising MPLS TE links
Router is not advertising itself through OSPF as an MPLS TE link.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
No targeted LDP session exists between peer PE's
Remote Site PE router is not accepting targeted LDP session requests.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
NA |
Yes |
NS |
Yes |
Yes |
Yes |
Blocking ACL causing targeted LDP session setup problem
Router has an access control list which is blocking LDP messages (on TCP port 646).
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
Targeted LDP not established/operational between PE's
LDP has been unable to establish a targeted session between the devices due to peer PE router being unreachable.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
Tunnel Connectivity Failure No Targeted LDP Configuration
LDP discovery failure for the neighbor devices. The tunnel tail end device is not accepting LDP targeted hellos.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
For link protection, check that the backup tunnel does not pass through the protected interface
There is a FRR backup tunnel configured on the router. It is configured to protect a link on router (as NHOP), which is on the path the primary tunnel takes. However the configured backup tunnel is configured to traverse this link.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
Check the primary tunnel has FRR enabled with 'fast-reroute'
A tunnel has been detected on router. It appears that this tunnel is intended to be a primary tunnel, but it does not have the fast-reroute configuration as required.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
NA |
Yes |
NS |
Yes |
Yes |
Yes |
Node protection - Check if backup tunnel path is explicit and does not contain the protected node interface in path
There is a FRR backup tunnel configured on router. It is configured to protect a router (as NNHOP), which is on the path the primary tunnel takes. However the configured backup tunnel is configured to traverse a link on this router.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
Check if the primary & backup tunnel merge point is reachable
The merge point router for FRR primary tunnel and FRR backup tunnel is unreachable.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NS |
Yes |
Yes |
Yes |
TE ping failure
The ping mpls traffic-eng tunnel command returned failure.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
NA |
Yes |
NS |
Yes |
Yes |
Yes |
Tunnel operationally down
The show mpls traffic-eng tunnels command has indicated that the TE Tunnel is down.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
NA |
Yes |
NS |
Yes |
Yes |
Yes |
Tunnel Connectivity Failure
Unknown MPLS TE connectivity problem.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
NA |
Yes |
Yes |
Yes |
Unable to Troubleshoot MPLS TE Connectivity Problem
Router is running a non-OAM Cisco IOS version. The connectivity of the tunnel cannot be tested.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Unknown LSP Connectivity Problem
LSP connectivity problem, data plane issue, or unknown cause.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Unsupported IOS Version
Core router running an unsupported IOS version. This version of IOS does not support the required OAM functionality.
|
|
|
|
|
|
|
|
|
Yes |
NA |
Yes |
Yes |
Yes |
Yes |
NA |
Yes |
NS |
VPN Connectivity Tests have been Exercised and No Failures Found (However as Pings are Blocked to the CE, it is Not Possible to Verify VPN Connectivity)
Unable to verify VPN connectivity in VRF from PE to destination.
|
|
|
|
|
|
|
|
|
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Yes |
Customer Site
Possible Customer Routing Issue
The PE has some routes from the CE, but the CE is unable to respond to pings.
|
|
|
|
|
|
|
|
|
Yes |
Yes |
Yes |
NA |
NA |
Yes |
Yes |
Yes |
Yes |
IOS XR Support
This section details the IOS XR support caveats:
1. MPLS Not Enabled On Interface
IOS XR has the concept of packages. One of the packages relevant to Diagnostics is the MPLS package. When Diagnostics troubleshooting focuses on an IOS XR router in the core, various preparation checks are carried out to ensure that the router is configured sufficiently; that is, that the MPLS package is installed and active, and then to check for the required features being enabled (MPLS OAM and MPLS LDP). If any of these checks fail, a failure scenario is reported. MPLS Not Enabled On Interface remains valid for IOS devices, or when MPLS is disabled on an interface on an IOS XR device.
2. CEF Not Enabled On Router
It is still possible for Diagnostics to determine cases where CEF is disabled on IOS routers in the core, for example, CEF could be disabled via CLI configuration, or when the router is overloaded and shuts itself down. In such cases, the IOS CLI command show cef state reports that CEF is either enabled/running or disabled/not running, and Diagnostics can determine that CEF is disabled.
CEF cannot be disabled on an IOS XR router. When the CEF switching feature on an IOS XR router becomes overloaded, it does not shut down. Instead, it applies back pressure to the queue of outstanding requests in an effort to reduce the load on the CEF switching process. Therefore, in an IOS XR router, the relevant CLI show command does not report that CEF is non-operational, and thus this failure scenario is not valid on an IOS XR router.
3. LDP/TDP Mismatch
This is not a valid scenario where directly connected IOS XR routers are present, because IOS XR only supports a single label distribution protocol - that is LDP. It is possible for the application to find LDP-TDP mismatch if it is configured in IOS-IOS XR, IOS XR-IOS, or IOS-IOS configurations.
4. Broken LDP Neighbor Session
Label Inconsistency
LDP Label Mismatch
LDP Neighbors Not Discovered
LSP Reply Path Problem
Missing LFIB Entry
Missing or Untagged Return Path
No Entry for Label
No Valid Next-Hop Entry
These failure scenarios are due to specific bugs in IOS versions, and are not applicable to IOS XR.
5. ATM Interface Is Protocol Down
ATM Sub-interface is Protocol Down
Intermittent ATM Failure (to the ATM Next Hop)
Intermittent ATM Failure (to the Destination)
Static IP address on ATM Point-to-Point Interface
Undiagnosed ATM Failure (ATM Pings Failed but the ATM Segment Ping Succeeded)
Undiagnosed ATM Failure (End to End and Segment ATM Pings Failed)
These failures are not supported in case of ATM interfaces on the CRS-1 platform. However, they continue to be applicable on IOS devices and for IOS XR on the Cisco 12000 XR Series.
IPv6 Support
This section details the IPv6 support caveats:
•In addition to IPv4 troubleshooting for both IOS and IOS XR devices, troubleshooting is extended for the IOS XR devices where IPv6 addressing is used on the PE-CE link. IPv6 is not supported on IOS devices.
• Ethernet is the only Access Circuit interface technology on which Diagnostics can troubleshoot, when IPv6 addressing is used on IOS XR devices.
• IPv6 support is extended only to support eBGP as the PE-CE routing protocol.
•Since the scope of the IPv6 address is only between the attachment circuit links, it is assumed that both ends of the LSP to have either IPv6 or IPv4 and not IPv6 at one end and IPv4 at the other and vice-versa.
• IPv6 support can troubleshoot PE-CE links configuration with Global Unicast IPv6 address alone.
• For IPv6 support, IPv4 router-id will be used for identification of Peer Routers, for protocols including BGP and LDP.
• Unlike in case of IPv4, the CE Access Circuit Interface IP address (for applicable test types) will not be auto populated as IPv6 unnumbered is not supported on IOS XR devices and there is no concept of /30 and /31 address in IPv6.
•The below failure scenarios although applicable on IOS XR, not applicable in IPv6 context as these validations are performed during initial data validations. The failure scenario to report that the CE access circuit interface IP address is a network address is performed during initial data validations. There is no concept of Broadcast address in IPv6.
–Broadcast Address
–Network Address
Observations
Observations are conditions that could lead to connectivity problems. Because Diagnostics cannot categorically conclude the cause of the connectivity problem, these conditions are reported as observations.
For more information, e-mail: mpls-diagnostics-expert@cisco.com
ACL Configured on PE
There is an access control list (ACL) configured on the provider edge (PE) router. It might be causing failure of the VPN routing/forwarding instance (VRF) ping from this PE to the remote PE, however we have not analyzed the ACL to confirm its usage. This is not causing the connectivity failure from the PE to the local customer edge (CE) router, or customer device.
BGP Neighbor Session Problem
Possible border gateway protocol (BGP) neighbor session problem detected. Displays table with columns BGP Neighbor (Neighbor IP Address) and BGP State (BGP Neighbor State).
BGP Router ID is Not a Loopback Interface
The local BGP router ID on the PE is not assigned to a loopback interface. It is recommended that the router ID is taken from a loopback interface to both reduce the chance of duplication and enhance stability.
Connected Routes Not Redistributed into MP-BGP
Directly connected routes might not be redistributed into MP-BGP.
Core Troubleshooting Could Not be Performed. The VPN Route is External.
Core troubleshooting could not be performed. Diagnostics is unable to determine the label-switched path (LSP) to test, because the PE <PE Name> has no valid VPN route to the remote prefix <IP address> within the VRF <VRF name>. The route is not learned through an internal Border Gateway Protocol (BGP) VPNv4 neighbor. It is known through the <Routing Protocol Name>. The next-hop for this external route is <IP address>. Traffic does not flow through the MPLS core, as expected. This might be an intentional back door link, however, it is often a symptom of PE - CE misrouting. To test LSP connectivity, you might want to run a PE to PE Core test that allows you to specify the LSP endpoints manually.
Core Troubleshooting Could Not be Performed. The VPN Route is External and the Next-Hop Is Inaccessible.
Core troubleshooting could not be performed. Diagnostics is unable to determine the LSP to test, because the PE <PE Name> has no valid virtual private network (VPN) route to the remote prefix <IP address> within the VRF <IP address>. The route is not learned through an internal BGP VPNv4 neighbor. It is known through the <Routing Protocol Name>. The next-hop for this external route is inaccessible. This might be an intentional back door link, however, it is often a symptom of PE - CE misrouting. To test LSP connectivity, you might want to run a PE to PE Core test that allows you to specify the LSP endpoints manually.
Core Troubleshooting Could Note be Performed. The VPN Route Next-Hop is Inaccessible.
Core troubleshooting could not be performed. Diagnostics is unable to determine the LSP to test, because the PE <PE Name> has no valid VPN route to the remote prefix <IP address> within the VRF <VRF name>. The next-hop is inaccessible. This might be due to a problem within the Core Interior Gateway Protocol (IGP) or IP connectivity failure. To test LSP connectivity, you might want to run a PE to PE Core test that allows you to specify the LSP endpoints manually.
Duplicate BGP Router ID
BGP Router Identifier on the PE is found to be duplicated on one or more interfaces of the listed devices.
eBGP Maximum Prefixes
The exterior border gateway protocol (eBGP) session between the PE and an eBGP neighbor has a maximum prefix count configured on the PE. There are currently X prefixes in the VRF from this neighbor.
eBGP Neighbor Not Established
It appears that you are running eBGP as your PE-CE routing protocol. The PE and CE interfaces are on different subnets and there is no route to the CE on the PE. Until there is a route to the CE, this eBGP session is not established.
eBGP Neighbors Not Established
eBGP neighbors have been specified in a VRF but are not established and are unreachable.
EIGRP Peer Relationship Not Established
The PE interface is configured with IP unnumbered. The CE interface must either also be using IP unnumbered or be on the same subnet in order for the enhanced interior gateway routing protocol (EIGRP) to establish a peer relationship.
Full-Mesh VPN Topology
These routers appear to be connected via a fully meshed VPN configuration. If this is not correct, there is an issue with the route target configuration.
Hub and Spoke VPN Topology
These routers appear to be connected via a hub and spoke VPN configuration. If this is not correct, there is an issue with the route target configuration.
Hub To Hub, Hub and Spoke VPN Topology
These routers appear to be connected via a hub to hub, hub and spoke VPN configuration. If this is not correct, there is an issue with the route target configuration.
Incomplete CEF Adjacencies
Incomplete Cisco express forwarding (CEF) adjacencies on the access circuit interface.
Incorrect Multilink Virtual-Access Interface Specified
If you are specifying a multilink access circuit interface for the PE ensure that the virtual access interface specified is an active multilink bundle interface and that it has active bundle links.
Interface Not In VLAN
Warning: Ethernet access circuit interface is not associated with a virtual LAN (VLAN).
Intermittent Ping Success
The ping showed only intermittent connectivity.
Inverse ARP Disabled on FR Interface
The Frame Relay interface is dynamically configured but has inverse address resolution protocol (ARP) explicitly disabled.
Inverse ARP Implicitly Disabled on FR Interface
There is a Frame Relay static map on the interface. This interface is configured dynamically but the presence of the static map will, as a side effect, disable inverse ARP.
LMI Disabled on Frame Relay Interface
Warning: Frame Relay permanent virtual circuit (PVC) status cannot be checked on interface because the local management interface (LMI) is disabled.
LSP Endpoint is Not a Loopback Interface
The VPNv4 route is being sent to IBGP neighbor(s). However, the next hop address is one of the directly connected physical interfaces. It is recommended to use loopback interfaces as the next hops for VPNv4 IBGP neighbors. If the address is not available at the correct hop via the IGP, it could break connectivity between VPN sites because no forwarding label information is available.
MPLS OAM Package is not enabled on IOS XR Router
MPLS OAM package is not enabled on the IOS XR router.
MPLS TE Package is not Enabled on IOS XR Router
MPLS TE package is not enabled on the IOS XR router.
Multiple Equal Cost Paths
Equal cost multiple paths (ECMP) were found.
Non-compliant IOS Version on PE Router
Core troubleshooting could not be performed because the provider edge (PE) router is running a non MPLS OAM compliant Cisco IOS version.
No Routes Received from eBGP
It appears that you are running eBGP as your PE-CE routing protocol. However, no routes have been received from the neighbor.
No Route to Remote Prefix Received from eBGP
It appears that you are running eBGP as your PE-CE routing protocol. However, the route to a remote prefix has not been received from the neighbor. Check PE and customer edge (CE) BGP configuration.
No VPN Label in VRF for Prefix
No virtual private network (VPN) label was found for the address in the VPN routing/forwarding (VRF) on the device.
OSPF Peer Relationship Not Established
The PE interface is configured with IP unnumbered. The CE interface must either also be using IP unnumbered or be on the same subnet in order for open shortest path first (OSPF) to establish a peer relationship.
PE-PE Core Only Test Performed and the Optional Loopback IP Address Parameters Have Not Been Supplied
The LSP under test was selected based on the BGP router-id of the remote site PE. If the network has multiple LSPs between the two PEs, the reported result might not accurately reflect the state of the LSP used for customer traffic. To ensure the correct LSP is tested, you can supply the LSP endpoints on the test input window.
Possible Backup Link
The ping from the PE to the destination prefix succeeded, however the route from the PE to the destination prefix has not been learned via the expected PE interface. There might be a backup link in operation, or you might have input the incorrect parameters.
Possible Blocking Route Map
A route map is configured on the PE which might be causing route traffic to be lost. If this is an intranet/extranet VPN configuration, then there might be a route map configuration error.
Possible Core IP Failure
The internet control message protocol (ICMP) ping issued from the local PE to the remote PE failed. There is no route to the remote PE in the Interior Gateway Protocol (IGP) route table of the local PE. Try troubleshooting IP connectivity between these devices.
Possible Ethernet Duplex Mismatch
Warning: Access circuit interface has late collisions. This might be caused by an Ethernet duplex mismatch.
Route Limit Reached
The route count on the device has reached the route limit.
Traceroute Not Transmitted
The MPLS traceroute was not transmitted.
This chapter provides details of all IOS and IOS XR commands executed by the troubleshooting workflow in the Cisco Prime Diagnostics application for the Cisco Prime Fulfillment 6.1 release.
IOS Commands
This section lists the IOS commands used by Diagnostics. If TACACS+ (or another authentication/authorization system) is used, ensure that these are all allowed for Diagnostics.
Note This list might be updated when Diagnostics releases or patches are made available, e-mail: mpls-diagnostics-expert@cisco.com for the latest list.
1. attach <slot> show version
2. execute-on slot <slot> 'show mpls forwarding-table <destinationPrefix> <subnetMask>'
3. execute-on slot <slot> 'show mpls forwarding-table <destinationPrefix>'
4. execute-on slot <slot> 'show mpls forwarding-table vrf <vrfName> <destinationPrefix> <subnetMask>'
5. execute-on slot <slot> 'show mpls forwarding-table vrf <vrfName> <destinationPrefix>'
6. execute-on slot <slot> 'show mpls forwarding-table vrf <vrfName>'
7. execute-on slot <slot> 'show mpls forwarding-table'
8. execute-on slot <slot> show ip cef vrf <vrfName> <networkPrefix>
9. execute-on slot <slot> show ip cef vrf <vrfName> <networkPrefix> <subnetMask>
10. execute-on slot <slot> show version
11. ping (interactive)
12. ping <targetIp>
13. ping mpls ipv4 <targetIp>/<targetIpSubnetMask> source <source> sweep <minSweepSize> <maxSweepSize> <sweepInterval> <repeatCount> timeout <timeout> replyMode <replyMode>
14. ping mpls traffic-eng Tunnel <tunnelNumber>
15. ping vrf <vrfName> (interactive)
16. show access-lists <listName>
17. show atm map
18. show atm pvc <interface>
19. show cef drop
20. show cef drop | include ^<slot>
21. show frame-relay lmi
22. show frame-relay lmi interface <interface>
23. show frame-relay map
24. show frame-relay pvc <interface> dlci <dlci>
25. show interfaces <interface>
26. show ip bgp summary
27. show ip bgp vpnv4 <vrfName> rib-failure
28. show ip bgp vpnv4 all neighbors
29. show ip bgp vpnv4 all neighbors <destIp>
30. show ip bgp vpnv4 all | include local router
31. show ip bgp vpnv4 vrf <vrfName> <networkPrefix>
32. show ip bgp vpnv4 vrf <vrfName> neighbors <destIp>
33. show ip bgp vpnv4 vrf <vrfName> <prefix> <subnetMask>
34. show ip bgp vpnv4 vrf <vrfName> labels | include <networkPrefix>/<subnetMask> | [0-9]+\.[0-9]+\.[0-9]+\.[0-9]+
35. show ip bgp vpnv4 vrf <vrfName> labels | include <classfulPrefix>
36. show ip bgp vpnv4 vrf <vrfName> labels | include <networkPrefix>/<subnetMask>
37. show ip cef <destinationPrefix>
38. show ip cef summary
39. show ip cef vrf <vrfName> <networkPrefix> <subnetMask> detail
40. show ip cef vrf <vrfName> <networkPrefix> detail
41. show ip cef vrf <vrfName> adjacency <interface> <destip> detail
42. show ip eigrp <vrfName> interfaces <vrfInterface>
43. show ip interface <interface>
44. show ip interface <interface> | include access list is
45. show ip interface brief <interface>
46. show ip interface brief | include <ip-address>
47. show ip ospf <processId> <area> interface <intName>
48. show ip ospf mpls traffic-eng link
49. show ip protocols <vrfName>
50. show ip route <targetIp>
51. show ip route vrf <vrfName> <targetIp>
52. show ip traffic
53. show ip vrf detail <vrfName>
54. show ip vrf interfaces <vrfName>
55. show mpls forwarding-table <destinationPrefix>
56. show mpls forwarding-table <destinationPrefix> <subnetMask>
57. show mpls forwarding-table <destinationPrefix> detail
58. show mpls forwarding-table labels <label>
59. show mpls forwarding-table labels <label> detail
60. show mpls forwarding-table vrf <vrfName>
61. show mpls forwarding-table vrf <vrfName> <destinationPrefix>
62. show mpls forwarding-table
63. show mpls interfaces <interface>
64. show mpls interfaces all
65. show mpls ip binding <destinationPrefix> <destinationMask>
66. show mpls ip binding local
67. show mpls ip binding summary
68. show mpls label range
69. show mpls ldp bindings <ip> <subnetMask>
70. show mpls ldp bindings neighbor <neighbor ip> <subnetMask>
71. show mpls ldp discovery
72. show mpls ldp neighbor
73. show mpls ldp neighbor <interface>
74. show mpls traffic-eng tunnels
75. show mpls traffic-eng tunnels <status>
76. show mpls traffic-eng tunnels <tunnelId>
77. show mpls traffic-eng tunnels destination <destination> <status>
78. show mpls traffic-eng tunnels destination <destination>
79. show mpls traffic-eng tunnels role <role>
80. show mpls traffic-eng tunnels role <role> <status>
81. show mpls traffic-eng tunnels role <role> destination <destination> <status>
82. show mpls traffic-eng tunnels role <role> destination <destination> up
83. show mpls traffic-eng tunnels role head brief
84. show ppp multilink interface <interface>
85. show route-map <mapName>
86. show running-config
87. show running-config interface <interface>
88. show running-config interface <interface> | include frame-relay interface-dlci
89. show running-config interface <interface> | include map-group
90. show running-config interface <interface> | include no frame-relay inverse-arp
91. show running-config | begin router bgp
92. show running-config | include advertise-
93. show running-config | include ldp password
94. show running-config | include mpls label protocol
95. show running-config | include no
96. show version
97. show vlans
98. traceroute mpls ipv4 <ipAddress>/<subnetMask> source <source> destination <destination> ttl 15
99. traceroute mpls traffic-eng Tunnel <tunnelNumber>
100. traceroute vrf <vrfName> (interactive)
IOS XR Commands
This section lists the IOS XR commands used by Diagnostics. If TACACS+ (or another authentication/authorization system) is used, ensure that these are all allowed for Diagnostics.
Note This list might be updated when Diagnostics releases or patches are made available, e-mail: mpls-diagnostics-expert@cisco.com for the latest list.
1. ping <targetIp>
2. ping atm interface <interface> <vpi>/<vci>
3. ping atm interface <interface> <vpi>/<vci> end-loopback
4. ping atm interface <interface> <vpi>/<vci> seg-loopback
5. ping mpls ipv4 <destination>/<subnetMask>
6. ping mpls ipv4 <destination>/<subnetMask> reply mode router-alert
7. ping mpls ipv4 <destination>/<subnetMask> source <source>
8. ping mpls traffic-eng Tunnel <tunnelId>
9. ping vrf <vrfName>
10. ping vrf <vrfName> <targetIp> <sourceInterface> <minSweepSize> <maxSweepSize> <sweepInterval>
11. show access-lists ipv4 <listName>
12. show bgp ipv4 all summary
13. show bgp vpnv4 unicast neighbors
14. show bgp vpnv4 unicast summary
15. 14. show bgp vpnv4 unicast vrf <vrfName> <networkPrefix>
16. show bgp vpnv4 unicast vrf <vrfName> <prefix> <mask>
17. show bgp vpnv4 unicast vrf <vrfName> labels
18. show bgp vrf <vrfName> advertised neighbor <neighboreId> summary | include <ceDeviceIpAddr>
19. show bgp vrf <vrfName> ipv4 unicast
20. show bgp vrf <vrfName> neighbors
21. show bgp vrf <vrfName> vpnv4 unicast neighbors
22. show cef ipv4 <destinationPrefix>
23. show cef ipv4 drops
24. show cef ipv4 drops location <slot>
25. show cef ipv4 summary
26. show cef vrf <vrfName> ipv4 <networkPrefix> detail
27. show cef vrf <vrfName> ipv4 <networkPrefix> <subnetMask> detail
28. show cef vrf <vrfName> <networkPrefix> <subnetMask> location <location>
29. show eigrp <vrfName> interfaces <vrfInterface>
30. show frame-relay lmi
31. show frame-relay lmi interface <interface>
32. show install active summary
33. show install inactive summary
34. show install location <slot>
35. show interfaces <interface>
36. show ip cef vrf <vrfName> adjacency <interface> <destip> detail
37. show ip ospf <processId> <area> interface <intName>
38. show ipv4 interface <interface>
39. show ipv4 interface brief <interface>
40. show ipv4 interface brief | include <ip-address>
41. show ipv4 traffic
42. show ipv4 vrf <vrfName> interface brief
43. show ipv4 vrf <vrfName> interface <interface>
44. show ipv4 vrf all interface brief
45. show mpls forwarding
46. show mpls forwarding labels <label>
47. show mpls forwarding prefix <destinationPrefix>/<subnetMask>
48. show mpls forwarding prefix <destinationPrefix>/<subnetMask> detail
49. show mpls forwarding vrf <vrf>
50. show mpls forwarding vrf <vrf> prefix <destinationPrefix>/<subnetMask>
51. show mpls forwarding vrf <vrfName> prefix <destinationPrefix>/<subnetMask> labels <label> location <location>
52. show mpls forwarding vrf <vrfName> prefix <destinationPrefix>/<subnetMask> location <location>
53. show mpls interfaces
54. show mpls interfaces <interface>
55. show mpls label range
56. show mpls label table summary
57. show mpls ldp bindings <ip> <mask>
58. show mpls ldp bindings neighbor <neighbor> <ip> <mask>
59. show mpls ldp discovery
60. show mpls ldp neighbor
61. show mpls ldp neighbor <interface>
62. show mpls traffic-eng tunnels
63. show mpls traffic-eng tunnels backup <tunnelId>
64. show mpls traffic-eng tunnels brief role head
65. show mpls traffic-eng tunnels <status> detail
66. show mpls traffic-eng tunnels <tunnel-id>
67. show mpls traffic-eng tunnels <tunnelNumber> detail
68. show mpls traffic-eng tunnels destination <destination>
69. show mpls traffic-eng tunnels name <name>
70. show mpls traffic-eng tunnels destination <destination> <status> detail
71. show mpls traffic-eng tunnels destination <destination> detail
72. show mpls traffic-eng tunnels detail
73. show mpls traffic-eng tunnels role <role> <status> detail
74. show mpls traffic-eng tunnels role <role> destination <destination> <status> detail
75. show mpls traffic-eng tunnels role <role> destination <destination> up detail
76. show mpls traffic-eng tunnels role <role> detail
77. show ospf
78. show ospf vrf <vrf>
79. show ospf border-routers | include ABR
80. show ospf | include ID
81. show ospf mpls traffic-eng link
82. show ospf vrf <vrfName> interface brief
83. show ospf vrf <vrfName> interface <interfaceName>
84. show protocols | include OSPF
85. show rib ipv4 tables
86. show rib vrf <vrf> ipv4 unicast statistics <protocolName>
87. show rib vrf <vrf> protocols
88. show rip vrf <vrf>
89. show route ipv4 <targetIp>
90. show route vrf <vrfName> ipv4 <targetIp>
91. show rpl route-policy <mapName>
92. show rsvp neighbors
93. show running-config
94. show running-config explicit-path name <explicitPathName>
95. show running-config interface <interface>
96. show running-config mpls ldp
97. show running-config mpls ldp label advertise
98. show running-config mpls traffic-eng
99. show running-config router bgp
100. show running-config router bgp <asNumber> vrf <vrfName> neighbor <neighborIpAddr>
101. show running-config router bgp <asNumber> neighbor-group <neighborGroupName>
102. show running-config router bgp | include redistribute <protocol>
103. show running-config router ospf
104. show running-config router <protocol ID> vrf <vrf>
105. show running-config rsvp interface <interface-name>
106. show vlan interface
107. show version
108. show vrf <vrfName> ipv4 detail
109. traceroute mpls ipv4 <destination>/<subnetMask>
110. traceroute mpls traffic-eng Tunnel <tunnelId>
111. traceroute vrf <vrf>
112. ping vrf <vrfName> <targetIpv6Address> <sourceInterface> <minSweepSize> <maxSweepSize> <sweepInterval>
113. show bgp vpnv6 unicast neighbors
114. show bgp vpnv6 unicast neighbors <destIp>
115. show bgp vpnv6 unicast vrf <vrfName> <networkPrefix>
116. show bgp vpnv6 unicast vrf <vrfName> <networkPrefix>/<subnetMask>
117. show bgp vpnv6 unicast vrf <vrfName> labels | include <networkPrefix>/<subnetMask>| [0-9A-Fa-f:]+[0-9A-Fa-f]*
118. show bgp vpnv6 unicast summary | include BGP router identifier
119. show bgp vrf <vrfName> ipv6 unicast
120. show bgp vrf <vrfName> ipv6 unicast advertised neighbor <neighborId> summary | include <ceDeviceIpAddr>
121. show cef ipv6 summary
122. show cef vrf <vrfName> ipv6 <networkPrefix> detail
123. show cef vrf <vrfName> ipv6 <networkPrefix>/<subnetMask> detail
124. show cef vrf <vrfName> ipv6 <networkPrefix> location <location>
125. show cef vrf <vrfName> ipv6 <networkPrefix>/<subnetMask> location <location>
126. show ipv6 interface <interface>
127. show ipv6 interface brief <interface>
128. show ipv6 vrf all interface brief
129. show ipv6 vrf <vrfName> interface brief
130. show ipv6 vrf <vrfName> interface <interface>
131. show rib ipv6 tables
132. show route ipv6 <targetIp>
133. show route vrf <vrfName> ipv6 <targetIp>
134. show vrf <vrfName> ipv6 detail
Unrecognized VPN Topology
These routers do not appear to be connected via any VPN configuration. If running a hub and spoke VPN architecture, ensure the test is being run from hub to spoke, not from spoke to spoke.
Tunnel configured with OSPF Affinity Values
The TE tunnel configuration for an OSPF process has affinity values configured, which could lead to tunnel head-end problems. The affinity values have been detected on the link interface.
Check for configured Tunnel metrics
A custom TE metric has been detected for tunnel on a link with custom TE weight. This may override the default IGP weight and may lead to tunnel problems if configured incorrectly.
Check Primary and Backup Tunnel Setup Priority Value
The backup tunnel has been configured with a higher setup priority value than the primary tunnel that it is protecting. This may lead to primary tunnel preemption in cases where the requested bandwidth for the tunnels is restricted.
Check Primary and Backup Tunnel Hold Priority Value
The backup tunnel has been configured with a higher hold priority value than the primary tunnel that it is protecting.
The backup tunnel is configured with a bandwidth request
The backup tunnel configured on head-end has been configured with a bandwidth request. However, tunnel interface has been allocated with lesser bandwidth.
The backup tunnel is configured with a dynamic path-option
The backup tunnel configured on the router has been configured with a dynamic path. The suggested configuration is to have explicit-paths for backup tunnels.
Explicit path contains loose or exclude entries
The explicit path configured for tunnel contains loose or exclude entries. These entries may prevent a tunnel being formed across the correct route.
LDP Router-Id is not a loopback interface
Device has configured LDP router ID with a non-loopback interface IP. This is not a suggested practice.
RSVP is not configured on Interface
An interface on device is not configured for RSVP.
PE Core Facing Interface Down
MPLS enabled core facing interfaces on PE <PE Name> are currently operationally down.