Setting The Mac Learning Limit On An Interface; Configuring The Unknown Frame Forwarding Rule After The Mac Learning Limit On An Interface Is Reached - H3C S7500E-X Configuration Manual

expires, the device deletes the entry. This aging mechanism ensures that the MAC address table can
promptly update to accommodate latest network topology changes.
A stable network requires a longer aging interval, and an unstable network requires a shorter aging
interval.
An aging interval that is too long might cause the MAC address table to retain outdated entries. As a
result, the MAC address table resources might be exhausted, and the MAC address table might fail
to update its entries to accommodate the latest network changes.
An interval that is too short might result in removal of valid entries, which would cause unnecessary
floods and possibly affect the device performance.
To reduce floods on a stable network, set a long aging timer or disable the timer to prevent dynamic
entries from unnecessarily aging out. Reducing floods improves the network performance. Reducing
flooding also improves the security because it reduces the chances for a data frame to reach
unintended destinations.
To set the aging timer for dynamic MAC address entries:
Step
Enter system view.
1.
Set the aging timer for
2.
dynamic MAC address
entries.

Setting the MAC learning limit on an interface

This feature limits the MAC address table size. A large MAC address table will degrade forwarding
performance.
The MAC learning limit does not take effect on TRILL ports.
To set the MAC learning limit on an interface:
Step
Enter system view.
1.
Enter Layer 2 Ethernet
2.
interface view.
Set the MAC learning limit on
3.
the interface.
Configuring the unknown frame forwarding rule
after the MAC learning limit on an interface is
reached
You can enable or disable forwarding of unknown frames after the MAC learning limit is reached.
In this document, unknown frames refer to frames whose source MAC addresses are not in the MAC
address table.
Command
system-view
mac-address timer { aging
seconds | no-aging }
Command
system-view
interface interface-type
interface-number
mac-address max-mac-count
count
7
Remarks
N/A
The default setting is 300
seconds.
The no-aging keyword disables
the aging timer.
Remarks
N/A
N/A
By default, the number of learned
MAC addresses is not limited.