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2950 switch port-security

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packetkiller

Technical User
May 28, 2008
7
CN
i have a 2950-12 cisco switch,
and i am trying to use switchport port-security command to secure my little lan.

my switch port fa0/1 connects to a hub,and there are 3 computers connect to the hub, and the hub connects to a router which provides internet access.

i want to assign a static mac address which is the router's mac to my switch port fa0/1, so i can prevent those 3 computers access my lan.

i typed commands in my switch:
sw(config-if)#switchport port-security maximum 1
sw(config-if)#switchport port-security violation shutdown
sw(config-if)#switchport port-security mac-address aaaa.bbbb.cccc

from my understanding, my switch mac-address-table will only have router's mac which i assigned.
however, it turned out there are 3 more mac addresses associated with port fa0/1
why is this happening?

by the way, the router functions as dhcp and dns as well, is there any association with dhcp broadcast request those computers send? results in my switch fa0/1 has more mac addresses
 
First of all did you enable port-security on the interface by first issuing the following:
Code:
Switch(config-if)# switchport port-security <cr>
if so try running this command:
Code:
Switch(config)# clear port-security dynamic interface <type><mod>/<num>

ex:
Switch(config)# clear port-security dynamic int g0/3

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)
 
i tried switchport port-security command, i got a rejection:
command rejected:not eligible for secure port.
also, i tried clear port-security dynamic inter fa0/1, and nothing happened, what is supposed to happen? all dynamic mac addresses will be cleared?
by the way, clear port-security dynamic inter fa0/1 does not work under config mode, it works under privileged mode.

thanks for your help
 
what is the operational mode of the port?? If it's dynamic it won't work

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)
 
ok, i know what i did wrong
i have to do switchport mode access first, then i can use all the switchport commands
also, the mac-address-table is cleared

thanks
 
bingo. glad you got it working.

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)
 
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