display interface register-tunnel
Use display interface register-tunnel to display register-tunnel interface information.
Syntax
display interface [ register-tunnel [ interface-number ] ] [ brief [ description | down ] ]
Views
Any view
Predefined user roles
network-admin
network-operator
mdc-admin
mdc-operator
Parameters
register-tunnel [ interface-number ]: Specifies a register-tunnel interface by its number. The device has only one register-tunnel interface, Register-Tunnel 0. If you specify the register-tunnel keyword, this command displays information about Register-Tunnel 0 regardless of whether you specify an interface number. If you do not specify the register-tunnel keyword, this command displays information about all interfaces.
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:
After receiving the first multicast data from the source, the source-side DR encapsulates the multicast data into a register message. Then, it forwards the message to the RP through the register-tunnel interface.
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.
The RP sends a join message toward the multicast source to build an SPT.
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 Maximum transmission 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 interfaces in route mode: Link: ADM - administratively down; Stby - standby Protocol: (s) - spoofing Interface Link Protocol Primary IP Description REG0 UP -- --
Table 43: Command output
Field | Description |
|---|---|
Current state | Physical link state of the interface. This field always displays UP. |
Line protocol state | Data link layer state of interface. This field always displays DOWN. |
Description | Description of the interface. It is not configurable. |
Maximum transmission unit | MTU of the register-tunnel interface. It is not configurable. |
Internet protocol processing: Disabled | The interface is not assigned an IP address and cannot process IP packets. |
Physical | Physical type of the interface. This field always displays Unknown, because the physical type of the interface is unknown. |
Last 300 seconds input rate | Average incoming rate in the last 300 seconds. This field always displays 0. |
Last 300 seconds output rate | Average outgoing rate in the last 300 seconds. This field always displays 0. |
Input | Number of incoming packets, incoming bytes, and discarded packets. This field always displays 0. |
Output | Number of outgoing packets, outgoing bytes, and discarded packets. This field always displays 0. |
Brief information on interfaces in route mode | Brief information about Layer 3 interfaces. |
Link | Physical link state of the interface. This field always displays UP. |
Protocol | Data link layer protocol state of the interface. This field always displays two hyphens (--) because the interface does not support a data link layer protocol. |
Primary IP | Primary IP address of the interface. This field always displays two hyphens (--) because the interface does not have a primary IP address. |
Cause | Cause for the physical link state of an interface to be DOWN. This field always displays Not connected because no physical connection exists. |
Description | Description of the interface. This field is empty because the interface cannot be configured with a description. |
Related command
reset counters interface register-tunnel