R0106-HP MSR Router Series MPLS Command Reference(V7)

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To use BFD for PW connectivity verification, you must execute the vccv bfd and mpls bfd enable
command on both ends of the PW.
Examples
# Configure BFD to verify PW connectivity, specify the BFD packet encapsulation type as raw-bfd, and
specify the BFD session parameter template as aaa.
<Sysname> system-view
[Sysname] pw-class test
[Sysname-pw-test] vccv bfd raw-bfd template aaa
Related commands
• display l2vpn pw bfd
• mpls bfd enable
• vccv cc
vccv cc
Use vccv cc to specify the VCCV control channel (CC) type.
Use undo vccv cc to restore the default.
Syntax
vccv cc { control-word | router-alert }
undo vccv cc
Default
No VCCV CC type is specified.
Views
PW class view
Predefined user roles
network-admin
Parameters
control-word: Specifies the VCCV CC type as type 1: PWE3 Control Word with 0001b as first nibble.
router-alert: Specifies the VCCV CC type as type 2: MPLS Router Alert Label.
Usage guidelines
The packets used to verify PW connectivity are collectively referred to as VCCV packets. A PE transfers
VCCV packets through a control channel (CC).
CCs include the following types:
• control-word—Identifies VCCV packets through the control word (PW-ACH, PW Associated
Channel Header). You can use this CC type only when the PW supports control word. For more
information about control word, see MPLS Configuration Guide.
• router-alert—Identifies a VCCV packet by adding an MPLS router alert label before the PW label.
After you execute this command in PW class view and specify the PW class for a PW, whether the
specified CC is used is determined by the configurations on both ends of the PW. If both PEs have
specified the same VCCV CC type, the specified VCCV CC type is used. Otherwise, the PEs do not use
any CC and they cannot establish a BFD session for the PW.