Setting The Aging Timer For Dynamic Mac Address Entries; Setting The Mac Learning Limit - HPE FlexFabric 5940 Series Configuration Manual

Setting the aging timer for dynamic MAC address
entries
For security and efficient use of table space, the MAC address table uses an aging timer for each
dynamic MAC address entry. If a dynamic MAC address entry is not updated before the aging timer
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An aging interval that is too long might cause the MAC address table to retain outdated entries.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

This feature limits the MAC address table size. A large MAC address table will degrade forwarding
performance.
To set the MAC learning limit on an interface:
Step
Enter system view.
1.
Enter interface view.
2.
Set the MAC learning limit on
3.
the interface.
Command
system-view
mac-address timer { aging
seconds | no-aging }
Command
system-view
•
Enter Layer 2 Ethernet
interface view:
interface interface-type
interface-number
•
Enter Layer 2 aggregate
interface view:
interface
bridge-aggregation
interface-number
mac-address max-mac-count
count
28
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 MAC address table
size is not limited on an interface.