Reference Guide
Version Description
6.5.1.0 Added support for MAC Learning-Limit on the LAG.
Usage Information
This command and its options are supported on physical interfaces, static LAGs,
LACP LAGs, and VLANs.
If you do not specify the vlan option, the MAC address counters are not VLAN-
based. That is, the sum of the addresses learned on all VLANs (not having any
learning limit configuration) is counted against the MAC learning limit.
MAC Learning Limit violation logs and actions are not available on a per-VLAN
basis.
With the keyword no-station-move option, MAC addresses learned through this
feature on the selected interface persist on a per-VLAN basis, even if received on
another interface. Enabling or disabling this option has no effect on already learned
MAC addresses.
After the MAC address learning limit is reached, the MAC addresses do not age out
unless you add the dynamic option. To clear statistics on MAC address learning,
use the
clear counters command with the learning-limit parameter.
NOTE: If you configure this command on an interface in a routed VLAN, and
after the MAC addresses learned reaches the limit set in the mac learning-
limit command, IP protocols are affected. For example, VRRP sets multiple
VRRP Masters and OSPF may not come up.
When a channel member is added to a port-channel and there is not enough ACL
CAM space, the MAC limit functionality on that port-channel is undefined. When
this occurs, un-configure the existing configuration first and then reapply the limit
with a lower value.
Related
Commands
• clear counters — Clear counters used in the show interface command.
• clear mac-address-table — clears the MAC address table of all MAC address
learned dynamically.
• mac learning-limit mac-address-sticky — Replaces deprecated no-station-
move
parameter.
• show mac learning-limit — displays MAC learning-limit configuration.
mac learning-limit learn-limit-violation
Configure an action for a MAC address learning-limit violation.
C9000 Series
Syntax
mac learning-limit learn-limit-violation {log | shutdown}
To return to the default, use the no mac learning-limit learn-limit-
violation {log | shutdown} command.
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