smart-link flush receive

Function

The smart-link flush receive command enables an interface to receive Flush packets and specifies the control VLAN ID and password for Flush packets.

The undo smart-link flush receive command disables an interface from receiving Flush packets.

By default, an interface rejects Flush packets.

Format

smart-link flush receive control-vlan { { vlan-id } &<1-10> [ password { simple | sha } password ] | all }

undo smart-link flush receive [ control-vlan { vlan-id | all } ] (interface view)

undo smart-link flush receive (port group view)

Parameters

Parameter	Description	Value
control-vlan vlan-id	Specifies the control VLAN ID of Flush packets that can be received.	The value is an integer that ranges from 1 to 4094.
password simple	Indicates that the password for sending Flush packets is in plain text. NOTE: The password is saved in the configuration file in cipher text for security.	-
password sha	Indicates that Flush packets sent from the Smart Link group contain an SHA-encrypted password. NOTE: The password is saved in the configuration file in cipher text for security.	-
password	Specifies the password carried in Flush packets.	The value is a string of 6 to 16 case-sensitive characters in plain text and consists of at least two of the following: lowercase letters, uppercase letters, digits, and special characters excluding question marks (?) and spaces.
all	Indicates that all control VLANs allow Flush packets.	-

Views

Ethernet interface view, GE interface view, XGE interface view, 25GE interface view, 40GE interface view, 100GE interface view, MultiGE interface view, Eth-Trunk interface view and port group view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

When a switchover occurs between the master and slave links in a Smart Link group, the existing forwarding entries do not apply to the new topology. All the MAC address entries and ARP entries on the network need to be updated. The Smart Link group sends Flush packets to notify upstream devices of the topology change. Upstream devices can update their MAC address entries and ARP entries only if they are enabled to receive Flush packets. If a device rejects Flush packets, it cannot forward packets correctly after a link failover occurs in the Smart Link group.

Precautions

The Flush packets mentioned here are used only for communication between Huawei CE series and S series switches. Other manufacturers may define different Flush packet formats.
The smart-link flush receive command does not add member interfaces of the Smart Link group to the control VLAN. You need to configure the member interfaces to allow the control VLAN. The interface accepts a Flush packet only if the control VLAN ID and password in the packet are the same as those configured on the local interface.
A maximum of 256 control VLANs used to receive Flush packets can be configured on an interface.
The original encryption mode and password are deleted after you run this command to configure the new ones. If the control VLAN ID is changed, the password must be reconfigured.
For security purposes, you are advised to use SHA as the authentication algorithm of Smart Link.
If the password is encrypted in the SHA mode, it cannot be retrieved. Set a new password after the original one is lost.

Example

# Enable GE0/0/1 to receive Flush packets with control VLAN ID 100 and password huawei-123.

<HUAWEI> system-view
[HUAWEI] interface gigabitethernet 0/0/1
[HUAWEI-GigabitEthernet0/0/1] smart-link flush receive control-vlan 100 password sha huawei-123