Brocade Multi-Service IronWare Administration Guide (Supporting R05.6.00) - Manual (Page 230)

212 Multi-Service IronWare Administration Guide
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LSP ping and traceroute
6
LSP ping TLVs
Table 34 lists the TLVs defined in RFC 3479 that are included in an echo request and reply.
The Brocade devices support sending and receiving downstream mapping TLVs without multipath
information (where the multipath type is always set to 0). Note that the detailed multipath
information can be used by the ingress LSR to ping or traceroute through all ECMP paths at the
transit LSR. Currently, the Brocade devices do not support LDP LSPs with ECMP. Consequently, the
multipath type of non-zero is not relevant in these operations.
LSP FEC types
For LDP LSPs, the LDP IPv4 prefix sub-TLV (sub-type = 1) is encoded in the target FEC stack of the
echo request. For RSVP LSPs, the RSVP IPv4 LSP sub-TLV (sub-type = 3) is encoded in the target
FEC stack.
NOTE
Static RSVP LSPs are no longer supported, so a ping or traceroute for a static LSP is not supported.
Redundant RSVP LSPs
For RSVP LSPs with redundant paths, ping or traceroute on a LSP is performed on the currently
active path. For example, if the secondary path is the active path for an LSP, the MPLS echo
request packets are sent out on the secondary path's interface.
If the active path changes while a ping or traceroute is in progress, the echo request continues to
be sent out on the old active path. This implies that the echo request that was sent after path
switchover times out. The user subsequently needs to restart the ping or traceroute.
TABLE 34 Show Cfm output descriptions
TLV type TLV name TX in echo request TX in echo reply
1 Target FEC stack Yes No
2 Downstream mapping Yes if the dsmap option is set Yes for transit LSRs only if
downstream mapping TLV is
included in the MPLS Echo
request.
3 Pad Depend on the size option Yes (if value = 2)
7 Interface and Label Stack N/A Yes if the I flag in DS
mapping is set
9 Errored TLV N/A Yes (if error is detected)
10 Reply TOS bytes Yes if reply-tos option is set TLV is not sent back. Just
copy TOS byte into IP header.