MAC Authentication Bypass on Catalyst 2950 supported?


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MAC Authentication Bypass on Catalyst 2950 supported?

Postby Daniel Alex » Fri, 16 May 2008 12:41:13 GMT

Hi all,

Which IOS release that supports MAC Authentication Bypass (MAB) for Catalyst 
2950 switch? Currently I have 12.1-22 EA8a version and I would like to use 
this feature.

Thanks very much.



Similar Threads:

1.Problems with Catalyst 2950 and Mac OS X 10.4 Systems


since we have replaced our Catalyst 2924XL switches with Catalyst 2950 
we get more and more problems with Apple Macintosh OS X 10.4 Systems 
with G5 processors.
The systems get their static IP addresses from two SuSE Linux 
DHCP-Servers. In our campus-LAN 76 VLANs are configured.

Normally everything works well, but sometimes some Mac OS X 10.4 systems 
lose suddenly their server mounts.
Sometimes other Mac OS X 10.4 systems dont get an IP address while 
booting. After a reboot it works regularly.
Deactivating the port-security doesnt help.
"Spanningtree portfast" and "switchport nonegotiate" is configured on 
the switchport.

Has anyone a hint on this problem?
Thanks in advance!
Kai Matthies

Our configuration:

CatXX#sh vers
Cisco Internetwork Operating System Software
IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(22)EA1b, RELEASE 
Copyright (c) 1986-2004 by cisco Systems, Inc.
Compiled Tue 24-Aug-04 00:12 by yenanh
Image text-base: 0x80010000, data-base: 0x8055C000

ROM: Bootstrap program is C2950 boot loader

Cat76 uptime is 47 weeks, 6 days, 7 hours, 32 minutes
System returned to ROM by power-on
System restarted at 15:05:25 MESZ Tue Jun 14 2005
System image file is "flash:/c2950-i6q4l2-mz.121-22.EA1b.bin"

cisco WS-C2950G-48-EI (RC32300) processor (revision Q0) with 20873K 
bytes of memory.
Processor board ID XXXXX
Last reset from system-reset
Running Enhanced Image
48 FastEthernet/IEEE 802.3 interface(s)
2 Gigabit Ethernet/IEEE 802.3 interface(s)

32K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address: xx:xx:xx:xx:xx:xx
Motherboard assembly number: 73-7409-12
Power supply part number: 34-0965-01
Motherboard serial number: XXXXX
Power supply serial number: XXXXX
Model revision number: Q0
Motherboard revision number: A0
Model number: WS-C2950G-48-EI
System serial number: XXXXXX
Configuration register is 0xF

CatXX#sh run int fast 0/22
interface FastEthernet0/22
  description XXX
  switchport access vlan 721
  switchport mode access
  switchport nonegotiate
  switchport port-security
  switchport port-security mac-address sticky
  switchport port-security mac-address sticky 0000.1111.2222
  no snmp trap link-status
  no cdp enable
  spanning-tree portfast

CatXX#sh int fast 0/22
FastEthernet0/22 is down, line protocol is down (notconnect)
   Hardware is Fast Ethernet, address is 0013.1953.xxxx (bia 0013.1953.xxxx)
   Description: XXX
   MTU 1500 bytes, BW 100000 Kbit, DLY 1000 usec,
      reliability 255/255, txload 1/255, rxload 1/255
   Encapsulation ARPA, loopback not set
   Keepalive set (10 sec)
   Auto-duplex, Auto-speed, media type is 100BaseTX
   input flow-control is unsupported output flow-control is unsupported
   ARP type: ARPA, ARP Timeout 04:00:00
   Last input 29w0d, output 01:18:10, output hang never
   Last clearing of "show interface" counters 3d12h
   Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
   Queueing strategy: fifo
   Output queue: 0/40 (size/max)
   5 minute input rate 0 bits/sec, 0 packets/sec
   5 minute output rate 0 bits/sec, 0 packets/sec
      276641 packets input, 102028305 bytes, 0 no buffer
      Received 1969 broadcasts (0 multicast)
      0 runts, 0 giants, 0 throttles
      0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
      0 watchdog, 1189 multicast, 0 pause input
      0 input packets with dribble condition detected
      797521 packets output, 121800493 bytes, 0 underruns
      0 output errors, 0 collisions, 0 interface resets
      0 babbles, 0 late collision, 0 deferred
      0 lost carrier, 0 no carrier, 0 PAUSE output
      0 output buffer failures, 0 output buffers swapped out

CatXX#sh int fast 0/22 switchport
Name: Fa0/22
Switchport: Enabled
Administrative Mode: static access
Operational Mode: down
Administrative Trunking Encapsulation: dot1q
Negotiation of Trunking: Off
Access Mode VLAN: 721 (XXX)
Trunking Native Mode VLAN: 1 (default)
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk private VLANs: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
Protected: false
Unknown unicast blocked: disabled
Unknown multicast blocked: disabled
Appliance trust: none

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5.Debug mac access-list extended 2950

Is there a way to debug extended mac access-lists?  I have not found
anything on the Cisco Web Sit or in my switch doc.

My layer2 acl is blocking everything and I do not have any way of
seeing what is happening.  show access-list does not provide a count of
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