HP 5900 Series Command Reference Manual page 129

brief: Displays brief information. If you do not specify this keyword, the command displays detailed
information.
description: Displays the full interface description. If you do not specify this keyword, the command
displays only the first 27 characters of the interface description.
down: Displays information about the interfaces in down state and the reasons why the interfaces are
down. If you do not specify this keyword, the command displays information about interfaces in all states.
Usage guidelines
The register-tunnel interface is a virtual interface that is automatically created by the system. You cannot
configure it or delete it, but you can display the interface information by using this command.
In the initial stage of multicast source registration, the register-tunnel interface is used to establish a
channel between the source-side DR and the RP to transmit multicast register messages. The process of
initial source registration is as follows:
1. After receiving the first multicast data from the source, the source-side DR encapsulates the
multicast data into a register message. The register message is forwarded to the RP through the
register-tunnel interface.
2. The register message reaches RP on the register-tunnel interface on the RP. The RP decapsulates the
register message and forwards the multicast data to the receiver hosts. At the same time, the RP
learns the IP address of the multicast source.
3. The RP sends a join message toward the multicast source to build an SPT.
4. After the SPT is built, the multicast data travels to the RP along the SPT rather than through the
register-tunnel interface.
Examples
# Display detailed information about Register-Tunnel 0.
<Sysname> display interface register-tunnel 0
Register-Tunnel0
Current state: UP
Line protocol state: DOWN
Description: Register-Tunnel0 Interface
Bandwidth: 0kbps
Maximum Transmit Unit: 1536
Internet protocol processing: disabled
Physical: Unknown
Last 300 seconds input rate: 0 bytes/sec, 0 bits/sec, 0 packets/sec
Last 300 seconds output rate: 0 bytes/sec, 0 bits/sec, 0 packets/sec
Input: 0 packets, 0 bytes, 0 drops
Output: 0 packets, 0 bytes, 0 drops
# Display brief information about Register-Tunnel 0.
<Sysname> display interface register-tunnel 0 brief
Brief information on interface(s) under route mode:
Link: ADM - administratively down; Stby - standby
Protocol: (s) - spoofing
Interface
REG0
Link Protocol Main IP
UP -- --
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Description