3Com Switch 8800 Advanced Software V5 Configuration Guide

66 CHAPTER 7: MAC ADDRESS TABLE MANAGEMENT CONFIGURATION
n
The aging time of the MAC address is available on all ports. The MAC address
aging timer takes effect only on dynamic MAC address entries (learned or
administratively configured) only.
Configuring Maximum
Number of MAC
Addresses an Ethernet
Port or a Port Group Can
Learn
To prevent a MAC address table from so large that it may degrade forwarding
performance, you may restrict the number of MAC addresses that can be learned.
One approach is to do this on a per-port or port group basis.
Follow these steps to configure the maximum number of MAC addresses that an
Ethernet port or port group can learn:
Configuring Maximum
Number of MAC
Addresses a VLAN Can
Learn
To prevent a MAC address table from getting so large that it may degrade
forwarding performance, you may restrict the number of MAC addresses that can
be learned. One approach is to do this on a per-VLAN basis.
Follow these steps to configure the maximum number of MAC addresses that a
VLAN can learn:
n
Since there are no layer 2 physical interfaces in the Super VLAN, and the number
of the learned MAC addresses is always 0, it is meaningless to configure the
maximum number of MAC addresses that the Super VLAN can learn.
To do... Use the command... Remarks
Enter system view system-view -
Enter
Ethernet
interface
or port
group
view
Enter Ethernet
interface view
interface interface-type
interface-number
Use either command
In the Ethernet interface view,
the following configurations
only take effect on the
current port; in the port
group view, the
configurations take effect on
all ports.
Enter port group
view
port-group { | manual
port-group-name |
aggregation agg-id }
Configure the maximum
number of MAC addresses that
can be learned on an Ethernet
port or port group or configure
whether frames with unknown
destination MAC addresses can
be forwarded or not after the
upper limit is reached
mac-address
max-mac-count { count |
disable-forwarding }
Required
The default maximum
number of MAC addresses
that can be learned is 14336.
After the upper limit is
reached, frames with
unknown destination MAC
addresses are forwarded by
default.
To do... Use the command... Remarks
Enter system view system-view -
Enter VLAN view vlan vlan-id -
Configure the maximum
number of MAC addresses
that can be learned on a
VLAN
mac-address
max-mac-count count
Required
172032 by default