Specifying The Preservation Time Of The Bridge Mac Address - H3C S9500E Series Configuration Manual

To do...
Enter system view
Configure the description for a
member switch

Specifying the preservation time of the bridge MAC address

A switch uses the bridge MAC address when it communicates with the external networks as a bridge.
Some Layer 2 protocols (like LACP) use bridge MAC addresses to identify different switches. During Layer
2 packet forwarding, if the destination MAC address of a packet is the bridge MAC address of a switch,
the packet is sent to this switch; otherwise, the packet is discarded. This means the bridge switch on your
network must have a unique bridge MAC address. If multiple devices on your network have the same
bridge MAC addresses, bridge MAC address collision occurs and the communication fails.
An IRF fabric communicates with external networks as a single switch and has a bridge MAC address.
Typically, an IRF fabric uses the bridge MAC address of its master.
Bridge MAC address collision causes communication failure, and bridge MAC address switching causes
traffic interruption. Properly configure the preservation time of the bridge MAC address of the IRF fabric
to avoid this issue.
• Bridge MAC address collision occurs and causes network communication problems when a master
leaves an IRF fabric to join another IRF fabric or to operate in a standalone manner and the IRF
fabric is configured to permanently preserve the bridge MAC address, bridge MAC address
collision occurs and thus causes network communication problem.
Unnecessary bridge MAC address switching occurs causing the flow interruption when the master
•
leaves the IRF fabric because of a reboot or link failure, and the IRF fabric is configured to change
its bridge MAC address as soon as the master leaves.
To avoid these issues, configure the preservation time of the bridge MAC address of the IRF fabric
according to your network status:
Preserve for six minutes: When the master leaves, the bridge MAC address does not change for six
•
minutes. If the master does not come back within six minutes, the IRF fabric uses the bridge MAC
address of the newly elected master as its bridge MAC address. If the master leaves for a short time
because of a master reboot or link failure, but then returns to the IRF fabric, specify this setting to
minimize flow interruption caused by unnecessary bridge MAC address switch.
Preserve permanently: The bridge MAC address of the IRF fabric does not change no matter how
•
long the master leaves the IRF fabric.
Not preserved: When the master leaves, the IRF fabric uses the bridge MAC address of the newly
•
elected master as its bridge MAC address.
To specify the preservation time of the bridge MAC address of the IRF fabric:
To do...
Enter system view
Configure
address of the IRF fabric to be
preserved permanently when the
master leaves
Use the command...
system-view
irf member member-id description text
Use the command...
system-view
the bridge MAC
irf mac-address persistent always
20
Remarks
—
Optional
Not configured by default.
Remarks
—
Optional
By default, the bridge MAC
address of the IRF fabric is