Command Line Reference Guide
Layer 2 | 841
Defaults
On C-Series, the default behavior is no-station-move + static.
On E-Series, the default behavior is station-move + static.
“Static” means manually entered addresses, which do not age.
Command Modes
INTERFACE
Command
History
Usage
Information
This command and its options are supported on physical interfaces, static LAGs, LACP LAGs, and
VLANs.
If the vlan option is not specified, then the MAC address counters is 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 will 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.
Once 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.
When a channel member is added to a port-channel and there is not enough ACL CAM space, then the
MAC limit functionality on that port-channel is undefined. When this occurs, unconfigure the existing
configuration first and then reapply the limit with a lower value.
Although you can convert manually-configured MAC addresses to sticky MAC addresses (mac
learning-limit no-station-move), it is not recommended.
Related
Commands
Version 8.3.1.0
Added
vlan option on E-Series.
Version 8.2.1.0 Introduced on S-Series
Version 7.7.1.0
Introduced on C-Series; added
station-move option
Version 6.5.1.0 Added support for MAC Learning-Limit on LAG
Note: If you configure this command on an interface in a routed VLAN, and once 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.
clear counters
Clear counters used in the show interface command
clear mac-address-table dynamic Clear the MAC address table of all MAC address learned dynamically.
show mac learning-limit Display MAC learning-limit configuration.