isis mesh-group

Function

The isis mesh-group command adds an interface to a specified mesh-group.

The undo isis mesh-group command deletes the interface from the mesh-group.

By default, an interface does not belong to any mesh-group and floods LSPs normally.

Format

isis mesh-group { mesh-group-number | mesh-blocked }

undo isis mesh-group

Parameters

Parameter	Description	Value
mesh-group-number	Specifies a mesh-group number.	The value is an integer ranging from 1 to 4294967295.
mesh-blocked	Blocks the interface so that no new LSPs are flooded on this interface.	-

Parameter

Description

Value

mesh-group-number

Specifies a mesh-group number.

The value is an integer ranging from 1 to 4294967295.

mesh-blocked

Blocks the interface so that no new LSPs are flooded on this interface.

Views

100GE interface view, 10GE interface view, 25GE sub-interface view, 25GE interface view, 400GE interface view, 40GE interface view, 50GE sub-interface view, 50GE interface view, Eth-Trunk interface view, FlexE interface view, GE optical interface view, GE electrical interface view, GMPLS-UNI interface view, Global VE sub-interface view, Loopback interface view, Tunnel interface view, VBDIF interface view, VE sub-interface view, VE interface view, VLANIF interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
isis	write

Usage Guidelines

Usage Scenario

When an interface that does not belong to an IS-IS mesh-group receives an LSP, the interface sends the LSP to all the other interfaces. On an NBMA network with multiple connections and P2P links, the same LSP will flood the network and consume bandwidth.

To address this problem, run the isis mesh-group command to add an interface to a mesh-group. Then, the interface sends the received LSP only to interfaces that do not belong to its mesh-group.

It is also mentioned in the agreement that in order to prevent the mesh-group feature from causing the database to be out of sync, the interface configured with the mesh-group should periodically flood CSNP. Therefore, when an interface of the device receives an LSP, other interfaces configured with mesh-group periodically send CSNP packets. After the peer device receives the CSNP packet, the peer device compares its own database and will do so when it finds that the LSP packet is missing. Send PSNP to request updated LSP packets. In this case, new LSP packets will also be sent on the mesh-group interface normally.

Prerequisites

IS-IS has been enabled on an interface using the isis enable command.

Configuration Impact

If all interfaces on a device are blocked, no packet can be sent, causing a database synchronization problem.

Precautions

When adding interfaces to mesh-groups or blocking interfaces, do not run the isis mesh-group command on all interfaces. This can prevent link faults from affecting the normal spreading of LSPs.

Example

# Add GigabitEthernet 0/1/1 to mesh-group 3.

<HUAWEI> system-view
[~HUAWEI] isis 1
[*HUAWEI-isis-1] quit
[*HUAWEI] interface GigabitEthernet 0/1/1
[*HUAWEI-GigabitEthernet0/1/1] isis enable 1
[*HUAWEI-GigabitEthernet0/1/1] isis mesh-group 3