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3850 Switch Stack MAC Address Issues

DundalkKid
Level 1
Level 1

Hi All,

Having a small issue at the moment with a 2 * 3850 switch stack.

The stack isn't displaying mac learned on certain ports. The ports affected are spread over both switches. There is 14 ports having this issue. All other ports are working fine.

I plugged my laptop into a working port and I could see the mac addres. I then plugged it into one of the ports having the issue and I could no longer see the mac address. When my laptop was connected to both ports I was able to get a DHCP address and connect to the rest of the network without issues. Likewise I'm able to ping the end devices connected to the ports.

The config on the switch ports is straight forward and is the same on all the ports.

Switch model  WS-C3850-48P       running version 03.02.02.SE

Anyone any ideas ? Upgrade the software ?

Thanks

Non Working Port

interface GigabitEthernet2/0/27
 description ** ACCESS PORT **
 switchport access vlan 204
 switchport mode access
 switchport voice vlan 203
 no snmp trap link-status
 storm-control broadcast level 5.00
 spanning-tree portfast
end

3850_PCB_1F#sh int g2/0/27
GigabitEthernet2/0/27 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is c025.5c12.029b (bia c025.5c12.029b)
  Description: ** ACCESS PORT **
  MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:12, output never, output hang never
  Last clearing of "show interface" counters 00:06:31
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 1000 bits/sec, 1 packets/sec
  5 minute output rate 268000 bits/sec, 80 packets/sec
     600 packets input, 142105 bytes, 0 no buffer
     Received 19 broadcasts (13 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 13 multicast, 0 pause input
     0 input packets with dribble condition detected
     28641 packets output, 11600076 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     5 unknown protocol drops
     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

3850_PCB_1F#sh mac add i g2/0/27
          Mac Address Table
-------------------------------------------

Vlan    Mac Address       Type        Ports
----    -----------       --------    -----

Working Port

interface GigabitEthernet2/0/19
 description ** ACCESS PORT **
 switchport access vlan 204
 switchport mode access
 switchport voice vlan 203
 no snmp trap link-status
 storm-control broadcast level 5.00
 spanning-tree portfast
end

3850_PCB_1F#sh int g2/0/19
GigabitEthernet2/0/19 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet, address is c025.5c12.0293 (bia c025.5c12.0293)
  Description: ** ACCESS PORT **
  MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX
  input flow-control is off, output flow-control is unsupported
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:05, output never, output hang never
  Last clearing of "show interface" counters 00:09:46
  Input queue: 0/2000/0/0 (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 321000 bits/sec, 106 packets/sec
     355 packets input, 27400 bytes, 0 no buffer
     Received 21 broadcasts (20 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 20 multicast, 0 pause input
     0 input packets with dribble condition detected
     52866 packets output, 21458519 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 unknown protocol drops
     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
3850_PCB_1F#sh mac add i g2/0/19
          Mac Address Table
-------------------------------------------

Vlan    Mac Address       Type        Ports
----    -----------       --------    -----
 204    ccf9.5496.582a    DYNAMIC     Gi2/0/19
 203    ccf9.5496.582a    DYNAMIC     Gi2/0/19
Total Mac Addresses for this criterion: 2

 

 

 

5 Replies 5

Aninda Chatterjee
Cisco Employee
Cisco Employee

Hello,

 

You could be hitting defect CSCuj51372.

 

Can you provide the following outputs (from a port where the mac-address is not being learned):

 

1.  show interfaces <> counters errors -> multiple iterations of these while the mac is not learned.

2.  show platform matm macTable vlan <>

 

Please mention the mac-address that should be learned so that I can parse through the matm output. Additionally, can you confirm that a shut/no-shut of the affected ports does not clear the issue?

 

Regards,

Aninda

Hi Aninda,

Thanks for coming back to me about this. I have included the details that you were looking for. Let me know if you need anything else.

Thanks,

Colm

 

 

 

Can you get me the show interfaces <> counter errors output please?

Regards,

Aninda

Hi Aninda,

 

I have attached the required details.

Thanks,

Colm

DundalkKid
Level 1
Level 1

Hi All,

An upgrade to 03.03.04.SE fixed the issue.

Thanks,

Colm

 

 

 

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