Flapping error messages

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  • Question
  • Updated 2 years ago
I'm experiencing two issues at this moment that I'm looking for some helps:

1- I'm seeing Flapping error message on my Cisco 3560
2- The port Eth1 on AP230 is not passing any traffic to switch. looks like is on Passive/Standby mode. 

Here are my configurations:
The AP230 is connected through Eth0 and Eth1 to a Cisco 3560.

On AP230:

Eth0 -> Port Gi0/19
Eth1 -> Port Gi0/23

Eth0: Native Vlan 1 - Allow Vlan 20,60
Eth1: Native Vlan 1 - Allow Vlan 30

On Switch:
interface GigabitEthernet0/19 description CORP_AND_PRIVATE_WIFI
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1,20,60
 switchport mode trunk

interface GigabitEthernet0/23 description GUEST_WIFI
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1,30
 switchport mode trunk

It appears the Switch talks to the management interface instead port Eth0 and Eth1 individually which means the switch is talking to same MAC address over two ports. 

Also, I'm NOT seeing any traffic on Eth1 which means whoever connects to GUEST SSID won't able  to talk to DHCP server. 

I would greatly appreciate for your help,
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Mohammad Yekrangian

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Posted 3 years ago

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We are experiencing same issue with Cisco 3750 and 60 AP 230, all was configured according Aerohive Docs. Very similar setup to the above.

here is AP config for Cisco:

switchport access vlan 70
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 70
 switchport trunk allowed vlan 1-200
 switchport mode trunk

We have VM appliance on the premises. Help would be appreciated.
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Mohammad Yekrangian

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Thanks to the Aerohive support technician,

Here is the answer for you:

Monitor > Select Your AP > Modify > Routing > Multiple Network Default Routing > New > [Add vlan ID] (in my case VLAN 30)

Now, GUEST traffic (VLan 30) goes through ETH1 !!! and the rest of traffic (VLAN 20, 60) goes through ETH0

About flapping message:
According to Aerohive Support, this is something normal. There is no way to force the physical interface (Eth0/Eth1) to communicate with switch behalf of itself. 

Based on my understanding, the physical interface talks to MGT0 and then MGT0 talks to switch. that is why on the switch you see the MAC address of the MGT0 interface.  

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M. Boekholt

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and how about when you get them instead of over you layer 2 switches that have the APs connected suddenly over our layer 3 switches every second flodding the layer 3 switch in the end with processors of 98 and 99%. It looks like in a second the client roams from 1 organisation to an other location from us and that every fews seconds. Whe use only 1 Ethernet port of the APs. Does anyone have suchs problems and maybe an aswer?