Reference Guide

Layer 2 | 873
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, un-configure the existing
configuration first and then reapply the limit with a lower value.
station-move (OPTIONAL) Enter the keyword station-move to allow a station move
on learned MAC addresses.
sticky
(OPTIONAL) C-Series and S-Series only: Enter the keyword sticky to
enable sticky MAC-address learning, which converts dynamically-learned
MAC addresses on a port or port-channel interface to “sticky” MAC
addresses that prevent trusted devices from moving to a different interface.
Version 8.4.2.3
Added the
sticky option on the C-Series and S-Series.
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.