Address table commands, Commands in this chapter, Address table – Dell POWEREDGE M1000E User Manual

Page 259: Commands

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Address Table Commands

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6

Address Table Commands

Static MAC Filtering allows the administrator to add a number of unicast or

multicast MAC addresses directly to the forwarding database. This is typically

a small number relative to the total size of the database. Associated with each

static MAC address is a set of source ports, a set of destination ports and

VLAN information.
Any packet with a particular static MAC address in a particular VLAN is

admitted only if the ingress port is in the set of source ports; otherwise, the

packet is dropped. On the egress side, the packet, if admitted, is sent out of all

the ports that are in the set of destination ports.
Upon ingress, each packet's destination MAC address is compared against the

forwarding database. If the address is not in the table, the packet is flooded to

all other ports in the VLAN. If the address is in the table, then it is checked to

see if it has been defined as a filter. If the MAC address is not defined as a

filter, then the packet is forwarded.
If the specific destination MAC address is defined as a filter, then the ingress

port number is compared to the set of source ports listed for the address. If

the port of ingress is not in the set of source ports, then the packet is

immediately discarded. If the ingress port is a member of the set of source

ports, then the packet is admitted.
For packets admitted because of a MAC filter match only, the following

additional steps are performed. Note that all other egress processing remains

unchanged. At the egress port, if the destination port number is in the set of

destination ports, the packet is forwarded. If the destination port is not in the

set of destination ports, then the packet is discarded.
Static entries are never aged and can only be removed by user command.

Commands in this Chapter

This chapter explains the following commands:

clear mac address-table

mac address-table static

show mac address-table

count

2CSPC4.XModular-SWUM200.book Page 259 Thursday, March 10, 2011 11:18 AM

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