Reference Guide

Recovering from Learning Limit and Station Move Violations
After a learning-limit or station-move violation shuts down an interface, you must manually reset it.
To reset the learning limit, use the following commands.
NOTE: Alternatively, you can reset the interface by shutting it down using the shutdown command and then re-enabling it
using the no shutdown command.
● Reset interfaces in the ERR_Disabled state caused by a learning limit violation or station move violation.
EXEC Privilege mode
mac learning-limit reset
● Reset interfaces in the ERR_Disabled state caused by a learning limit violation.
EXEC Privilege mode
mac learning-limit reset learn-limit-violation [interface | all]
● Reset interfaces in the ERR_Disabled state caused by a station move violation.
EXEC Privilege mode
mac learning-limit reset station-move-violation [interface | all]
NIC Teaming
Network interface controller (NIC) teaming is a feature that allows multiple network interface cards in a server to be
represented by one MAC address and one IP address in order to provide transparent redundancy, balancing, and to fully utilize
network adapter resources.
The following illustration shows a topology where two NICs have been teamed together. In this case, if the primary NIC fails,
traffic switches to the secondary NIC because they are represented by the same set of addresses.
Figure 64. Redundant NICs with NIC Teaming
When you use NIC teaming, consider that the server MAC address is originally learned on Port 0/1 of the switch (shown in the
following) and Port 0/5 is the failover port. When the NIC fails, the system automatically sends an ARP request for the gateway
or host NIC to resolve the ARP and refresh the egress interface. When the ARP is resolved, the same MAC address is learned
on the same port where the ARP is resolved (in the previous example, this location is Port 0/5 of the switch). To ensure that
the MAC address is disassociated with one port and re-associated with another port in the ARP table, configure the mac-
address-table station-move refresh-arp command on the switch at the time that NIC teaming is being configured
on the server.
NOTE:
If you do not configure the mac-address-table station-move refresh-arp command, traffic continues
to be forwarded to the failed NIC until the ARP entry on the switch times out.
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