Problem in Catalyst switch 3560 ???

[begad.nashaat]

I'm connecting two catalyst 3560 switches to each other using trunk port and I'm getting below logs on one of them. Any ideas ???

18:43:38: %SW_MATM-4-MACFLAP_NOTIF: Host ac7b.a15b.3c2c in vlan 40 is flapping between port Fa0/1 and port Fa0/7
18:45:00: %SW_MATM-4-MACFLAP_NOTIF: Host ac7b.a15b.3c2c in vlan 40 is flapping between port Fa0/1 and port Fa0/7
18:45:45: %SW_MATM-4-MACFLAP_NOTIF: Host ac7b.a15b.3c2c in vlan 40 is flapping between port Fa0/1 and port Fa0/7
18:46:39: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
18:46:53: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
18:46:55: %SW_MATM-4-MACFLAP_NOTIF: Host ac7b.a15b.3c2c in vlan 40 is flapping between port Fa0/1 and port Fa0/7
18:47:03: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/6 and port Fa0/1
18:47:06: %SW_MATM-4-MACFLAP_NOTIF: Host ac7b.a15b.3c2c in vlan 40 is flapping between port Fa0/1 and port Fa0/7
18:47:15: %SW_MATM-4-MACFLAP_NOTIF: Host 98f1.7093.5d50 in vlan 40 is flapping between port Fa0/1 and port Fa0/7
18:49:02: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
18:49:13: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
18:50:18: %SW_MATM-4-MACFLAP_NOTIF: Host ac7b.a15b.3c2c in vlan 40 is flapping between port Fa0/1 and port Fa0/7
18:55:09: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
18:55:22: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
18:56:34: %SW_MATM-4-MACFLAP_NOTIF: Host 201a.06f7.a482 in vlan 40 is flapping between port Fa0/1 and port Fa0/7
18:56:54: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
18:57:08: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
19:07:30: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
19:08:36: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
19:08:42: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/6 and port Fa0/1
19:10:18: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
19:15:54: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
19:16:01: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6
19:17:27: %SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6

[Leo Laohoo]

%SW_MATM-4-MACFLAP_NOTIF: Host 3c97.0e53.cdf3 in vlan 40 is flapping between port Fa0/1 and port Fa0/6

This error log means there is a wired client in your network that's running on VLAN 40.  The wired clients is connected to TWO (2) ports of your switch and NOT in an EtherChannel.  

To fix this problem, you have two choices: 

1.  Unpatch or disable either ports Fa0/1 or Fa0/6; or

2.  Configure EtherChannel on Fa0/1 & Fa0/6.  Enable NIC Teaming on the wired client side.

[LJ Gabrillo]

Do what Leo does QUICKLY! or you'll be in a LOOP, loops not good in network infra xD
99% CPU anyone? xD

Though seriously, do what Leo said pronto! 

[SANTHOSHKUMAR SARAVANAN]

Hi ,

 Can you share me show cdp neigbhors output from your cisco switch , likely mac resembles Intel as vendor , have you connected single server to two different switch ??

AC7BA1

Intel Corporate

HTH

Sandy

[Jerry Paul]

Hi,

Follow these steps to resolve your problem:

1. Remove the connection between both switches.

2. delete flash vlan.dat     //use this command to completely remove VLAN

3. write erase reload     //use this command to reload

4. Now create trunk on both sides

5. show vlan    //use this command and check that trunk port is not shown here

Now connect both switches.

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[LJ Gabrillo]

With all due respect Jerry, 

That troubleshooting step is not very good.
Are you trying to bring down their network?

Hi Begad, 
Just follow Leo's advise. 
Jerry's advise is making you restore to default the device.

[Leo Laohoo]

Follow these steps to resolve your problem:
1. Remove the connection between both switches.
2. delete flash vlan.dat     //use this command to completely remove VLAN
3. write erase reload     //use this command to reload
4. Now create trunk on both sides
5. show vlan    //use this command and check that trunk port is not shown here
Now connect both switches.

WTF, mate.  Have you gone bonkers or something?  Y'call that a solution?  

[LJ Gabrillo]

​That's what I said
Yeap! + + + +  to this 

[Tiago Marques]

put output config port trunk please!

this is the trunk port?!?

flapping between port Fa0/1 and port Fa0/6

flapping between port Fa0/1 and port Fa0/7