Setting The Aging Time Of Mac Address Entries; Setting The Maximum Number Of Mac Addresses A Port Can Learn - H3C S5100-SI Series Operation Manual

Operation Manual – MAC Address Table Management
H3C S5100-SI/EI Series Ethernet Switches

1.2.3 Setting the Aging Time of MAC Address Entries

Setting aging time properly helps effective utilization of MAC address aging. The aging
time that is too long or too short affects the performance of the switch.
If the aging time is too long, excessive invalid MAC address entries maintained by
the switch may fill up the MAC address table. This prevents the MAC address
table from being updated with network changes in time.
If the aging time is too short, the switch may remove valid MAC address entries.
This decreases the forwarding performance of the switch.
Table 1-5 Set aging time of MAC address entries
Enter system view
Set the aging time of MAC
address entries
Normally, you are recommended to use the default aging time, namely, 300 seconds.
The no-aging keyword specifies that MAC address entries do not age out.
Note:
MAC address aging configuration applies to all ports, but only takes effect on dynamic
MAC addresses that are learnt or configured to age.

1.2.4 Setting the Maximum Number of MAC Addresses a Port Can Learn

The MAC address learning mechanism enables an Ethernet switch to acquire the MAC
addresses of the network devices on the segment connected to the ports of the switch.
By searching the MAC address table, the switch directly forwards the packets destined
for these MAC addresses through the hardware, improving the forwarding efficiency. A
MAC address table too big in size may prolong the time for searching MAC address
entries, thus decreasing the forwarding performance of the switch.
By setting the maximum number of MAC addresses that can be learnt from individual
ports, the administrator can control the number of the MAC address entries the MAC
address table can dynamically maintain. When the number of the MAC address entries
learnt from a port reaches the set value, the port stops learning MAC addresses.
Operation
system-view
mac-address timer
{ aging age | no-aging }
Command
1-7
Chapter 1 MAC Address Table
Management
Description
—
Required
The default aging time is
300 seconds.