Specifications

1118
Cross-Platform Release Notes for Cisco IOS Release 12.0S
OL-1617-14 Rev. Q0
Resolved Caveats—Cisco IOS Release 12.0(28)S3
Workaround: Use the following ACL instead of the above-mentioned example:
access-list 101 permit udp any any fragments
access-list 101 deny udp any any eq 0
access-list 101 permit ip any any
• CSCsa64782
Symptoms: When an ingress ISE line card is used with a default route that iBGP learns over a MPLS
core, the following two symptoms may occur:
– The output of the show controllers tofab alpha mip stat | i MTU command may show traffic
drops.
– Traffic is incorrectly sent as “unlabeled” over the MPLS core.
Conditions: These symptoms are observed on a Cisco 12000 series when the traffic path follows a
recursive default route and when recursive load sharing occurs.
Workaround: Prevent outbound load sharing to the default route by changing the IGP metrics.
• CSCsa68301
Symptoms: Inter-MVPN traffic does not function on an Engine 4+ line card.
Conditions: This symptom is observed on a Cisco 12000 series and may occur with any Engine 4+
line card.
Workaround: There is no workaround.
• CSCsa68616
Symptoms: An IPC failure occurs and an OC-12 line card that is configured for Frame Relay over
MPLS resets.
Conditions: This symptom is observed on a Cisco 12000 series that runs Cisco IOS
Release 12.0(27)S1.
Workaround: There is no workaround.
Further Problem Description: The IPC failure and the line card reset occur after a depletion of the
elements in the FrFab 608 byte queue for the line card. Consecutive outputs of the show controllers
slot-number frfab queue command show a consistent and rapid leak of these buffers.
• CSCsa70274
Symptoms: A Cisco router may crash during an LSP traceroute when a transit router responds with
a downstream map TLV that contains a multipath length field that is set to 0, 1, 2, or 3.
Conditions: This symptom is observed during testing of the Cisco LSP ping draft version 3 in a
network that uses a later version of the LSP ping draft.
The implementation of draft version 3 does not handle the multipath length field settings correctly.
In draft version 3 and earlier drafts, there is an ambiguity on whether or not the multipath length
field includes the four bytes comprising of the hash-key type, depth limit, and multipath length
fields. As such, all implementations of the draft version 3 encode the length as four bytes and reply
with a multipath length of four bytes.
When an LSP traceroute is invoked and a transit router replies with a downstream map TLV that
contains a multipath length field that is set to a length shorter than four bytes, existing
implementations handle this situation incorrectly and cause memory packet memory to become
corrupted during the subsequent attempt to build an MPLS echo request packet. This situation
eventually causes the router to crash.
Workaround: If LSP traceroute implementations exist on a transit router that cause the transit router
to reply with a multipath length that is set to a value other than four, avoid using an LSP traceroute.