Specifications

1186
Cross-Platform Release Notes for Cisco IOS Release 12.0S
OL-1617-14 Rev. Q0
Resolved Caveats—Cisco IOS Release 12.0(28)S1
MSD: %Camr_VA-3-STATISTICS: VA statistics register: 0x0098 reports
VA_SO_PKT_LEN_ERR_COUNT = 3
– In the output of the show interface srp 1/1 command, the received error counters such as
“framer runts” and “input errors” have a large value.
– In the output of the show hard pxf cpu statistics interface srp 1/1 detail command, the
“destination unreachable” counter increases.
– In the output of the show hard pxf cpu statistics interface srp 1/1 detail command, the “zero
encap length” counter increases.
Conditions: This symptom is observed when all of the following conditions are present:
– A packet enters with or without an MPLS label.
– The router tries to send an ICMP packet to the source in any of the following situations:
* The packet is denied by an output security ACL.
* There is no route in the router to forward the packet.
* The time to live (TTL) of the packet expires.
* The packet is an ICMP echo request packet, and the router tries to send an ICMP echo reply
packet to the source.
– On the interface on which the packet enters, the ip unreachable command is enabled by default.
Workaround: Enter the no ip unreachable command on all interfaces of the router, which works in
the following two cases:
– The packet is denied by an output security ACL.
– There is no route in the router to forward the packet.
For other cases, there is no workaround.
• CSCef25866
Symptoms: Connectivity for destinations that are reachable via an MPLS TE tunnel may fail when
the tunnel is fast-rerouted. The loss of connectivity may result in loss of TCP sessions (BGP, LDP,
etc.) for those destinations.
When the problem happens, the output of the show ip cef network command shows “invalid cached
adjacency” for the tunnel but does not show “fast tag rewrite.”
Conditions: This symptom is observed when all of the following conditions are present:
– The adjacency of the primary tunnel becomes incomplete when FRR is active, as can be
observed in the output of the show adjacency type number command. Whether or not the
adjacency becomes incomplete is media-dependent. For example, with PPP the adjacency
becomes incomplete but not with HDLC.
– The primary tunnel is the only path to reach the prefix in question.
– The ip cef accounting non-recursive command is not enabled.
– A routing change occurs for the prefix after the FRR switchover. (This is topology dependent)
Workaround:
– Use HDLC encapsulation instead of PPP. This will prevent the adjacency from becoming
incomplete.
– Use forwarding adjacencies. This will prevent the routing change.
Further Problem Description: The symptom affects traffic that originates on the tunnel headend.
Transit traffic going through the tunnel is not affected. The symptom does not occur if there are
multiple paths to the destination (one of which is the tunnel).