Dell N1100-ON, Справочное руководство

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Layer 2 Switching Commands
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MAC Address Table Commands
Dell EMC Networking N1100-ON/N1500/N2000/N2100-
ON/N3000/N3100-ON/N4000 Series Switches
Dell EMC Networking switches implement a MAC Learning Bridge is
compliance with IEEE 802.1Q. The switches implement independent VLAN
learning (IVL). Dynamically learned MAC addresses are used to filter the set
of ports on which a frame is forwarded within a VLAN, that is, the destination
MAC address and ingress VLAN for a frame entering the switch is looked up
in the MAC address table and, if a match is found, the frame is forwarded out
the matching port(s). If no match is found, the frame is flooded out all ports
in the VLAN except for the ingress port.
When a frame is received on a port, the source MAC address (and VLAN) is
looked up in the MAC address table. If no matching entry is found, a new
entry is added to the MAC address table associated with the source port. If a
matching entry is found, the matching entry timestamp is refreshed such that
it will continue to remain in the MAC address table. Dynamic MAC address
entries for which no frames have been received within the aging period are
removed out of the MAC address table. The administrator can globally
configure the MAC address aging timer.
Administrators can configure static MAC address entries. Static MAC entries
are treated in the same manner as dynamic MAC address entries for the
purposes of frame forwarding. Static MAC addresses never age out of the
MAC address database and can only be removed by administrator action.
Port security allows the administrator to disable learning of MAC addresses
on selected interfaces. Dynamically learned MAC addresses are flushed on an
interface at the time port security is enabled. The interface then dynamically
learns MAC addresses up to the configured limit and no more. The
administrator may configure a limit of 0 in order to disable MAC learning on
the interface entirely. In this configuration, it is advisable to configure static
MAC entries on the interface in order to facilitate forwarding.