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Nexus 7k internal l2fm l2dbg output interpretation

GoncaloContente
Beginner
Beginner

Hi, while trying to troubleshoot a mac move, I have run the following command to see if i could get some information about this mac moves:

N7K01-CPDA-CORE1# sh system internal l2fm l2dbg macdb address 5cb9.01eb.d747 vlan 100
Legend
------
Db:  0-MACDB, 1-GWMACDB, 2-SMACDB, 3-RMDB,    4-SECMACDB
Src: 0-UNKNOWN, 1-L2FM, 2-PEER, 3-LC, 4-HSRP
     5-GLBP, 6-VRRP, 7-STP, 8-DOTX, 9-PSEC 10-CLI 11-PVLAN
     12-ETHPM, 13-ALW_LRN, 14-Non_PI_MOD, 15-MCT_DOWN, 16 - SDB
     17-OTV, 18-Debounce Timer, 19-AM, 20-PCM_DOWN, 21 - MCT_UP
     22-L2VPN, 23-EFP, 24-DRV 25-ELTM
Slot:0 based for LCS 19-MCEC 20-OTV/ORIB

 VLAN: 100 MAC: 5cb9.01eb.d747 FE ID: 2
  Time                     If/swid    Db Op                    Src Slot  FE  HW_ADDR Count
    Sun Feb  4 20:52:23 2018 0x1a015000 0  AGE                  3    0    2    0

 VLAN: 100 MAC: 5cb9.01eb.d747
  Time                     If/swid    Db Op                    Src Slot  FE  HW_ADDR Count
    Fri Feb  2 12:59:33 2018 0x1a015000 0  UPDATE               3    0    1    0
    Fri Feb  2 12:59:33 2018 0x1a015000 0  UPDATE               2    19   0    0 1
    Fri Feb  2 12:59:34 2018 0x1a015000 0  UPDATE               3    0    5    0
    Sun Feb  4 20:52:23 2018 0x1a015000 0  DELETE               0    0    15   0
    Mon Feb  5 08:36:44 2018 0xffffffff 0  NOT_FOUND_INS_PC     2    19   0    0
    Mon Feb  5 08:36:44 2018 0xffffffff 0  INSERT               2    19   0    0
    Mon Feb  5 08:36:44 2018 0x1a015000 0  UPDATE               3    0    2    0
    Mon Feb  5 08:39:27 2018 0x1a015000 0  UPDATE               3    0    0    0
    Mon Feb  5 08:39:27 2018 0x1a015000 0  UPDATE               3    0    1    0
    Mon Feb  5 08:39:27 2018 0x1a015000 0  UPDATE               3    0    3    0
    Mon Feb  5 08:39:27 2018 0x1a015000 0  UPDATE               3    0    4    0
    Mon Feb  5 08:39:27 2018 0x1a015000 0  UPDATE               3    0    5    0
    Mon Feb  5 08:39:27 2018 0x1a015000 0  NOT_FOUND_INS_PC     2    19   0    0
    Mon Feb  5 08:39:27 2018 0x1a015000 0  UPDATE               2    19   0    0 1
    Mon Feb  5 08:39:28 2018 0x1a015000 0  UPDATE               2    19   0    0

The If/swid of 0xffffffff is leading me into thinking that there some kind of flooding on the local system but i have no idea why.

 

Also i would like know if anyone can explain me what is the meaning of  NOT_FOUND_INS_PC?

 

Regards

Gonçalo Reis

4 Replies 4

Diana Karolina Rojas
Cisco Employee
Cisco Employee

Hello Gonzalo, 

 

When you see a mac address movement it is usually due to some of these causes: L2 loop, Wireless Clients roaming between Access Point, Vmotion or Misconfigured Active/Standby NIC Teaming

 

Cisco recommend this steps to solve that:

 

"When this log message is printed, the following steps can be used to track the source of the move:

  • Document the interfaces which are reporting the mac moving.
  • Log into the device that attaches to these interfaces and enable mac move notification there if not already enabled.
  • Follow this logic until you are able to track down the source of the mac move.

Command to enable mac move notification:

  • N7K/N9K: logging level l2fm 5

These commands are non intrusive and will only print additonal syslog messages pertaining to mac flaps." https://www.cisco.com/c/en/us/support/docs/switches/nexus-7000-series-switches/200424-Nexus-L2FM-4-L2FM-MAC-MOVE-syslog-expla.html

 

I tried to searh the meaning of this output "NOT_FOUND_INS_PC" but I can not find anything. I hope this anwers can help you to solve the problem.

 

---Do not forget to rate/mark useful post---

 

Regards,

Hi Diana,

Thank you for replying and for trying to help, the logs on one of the nexus are as follows:

 N7K02-RECT-CORE2 %L2FM-4-L2FM_MAC_MOVE: Mac fcaa.14aa.a1bc in vlan 100 has moved from  100.0.65535 to  100.0.3050

As you can see the mac move is from a non-physical port to a physical port.

 

If i convert 3050 to hex i get 0x0BEA, then with the command

N7K01-CPDA-CORE1# sh system internal pixm info ltl 0x0bea

Member info
------------------
Type            LTL
---------------------------------
PHY_PORT       Eth1/22

or

N7K01-CPDA-CORE1# sh system internal pixm info | in 0x1a015000
0x0bea 0x1a015000  Eth1/22      2    1

i can see which is the physical port.

 

Now for the port 100.0.65535, when i convert 65535 to hex, i get ffff, if i look for this port the switch says it is not configured.

N7K01-CPDA-CORE1# sh system internal pixm info ltl 0xffff
0xffff is not configured

or

N7K01-CPDA-CORE1# sh system internal pixm info | in 0xffffffff

I don't know what is this port 100.0.65535 and what is used for, this is what i have been trying to found for the last days. i also have another post about this.

 

Regards

Gonçalo Reis

Do you have high CPU use? and do you have port-channels that involve the physical interface Eth1/22?

 

---Do not forgate to rate useful post---

 

Regards,

Hi Diana,

I dont have any of that, the CPU is very low and the interface eth 1/22 is not on a port channel.

 

Regards

Goncalo Reis

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