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I have a Brocade ICX 7450-48F with a 1G connection to my Cisco 3560 but the trunk is flapping

  • 1.  I have a Brocade ICX 7450-48F with a 1G connection to my Cisco 3560 but the trunk is flapping

    Posted Feb 05, 2019 08:22 AM

    Good morning,

     

    The facts:

    I have a Brocade ICX 7450-48F switch that is being used as my Distribution Switch for my small network. It has a single 1G connection to a Cisco 3560 via single mode fiber.

     

    The ICX is configured with 

    Port-name

    Dual-mode X

     

    The Cisco device is configured with

    trunk encapsulation dot1q

    switchport trunk native vlan (X to match the ICX)

    switchport trunk allowed vlan 1 - X

    switchport mode trunk

    switchport nonegotiate

    mls and qos configurations

     

    The Issue: The ICX connection to the Cisco device is flapping, meaning I am losing connection to the downstream Cisco device. A Show Log reveals that interface e 1/1/3 is receiving STP State messages for each of my configured VLANS, meaning that each VLAN in the log is cycling through its Listen Learn Forward State 

    for example : 

    VLAN X Port 1/1/3 STP State -> Listening (MakeFwding)

    VLAN X Port 1/1/3 STP State -> Learning (FwDlyExpiry)

    VLAN X Port 1/1/3 STP State -> Forwarding (FwDlyExpiry)

     

    I don't understand why STP is frequently updating itself causing the interface to bounce. Could this be avoided if I add a second 1G trunk between the ICX and Cisco device?


    #BrocadeICX7450
    #TrunkFlapping
    #TheWaterCooler


  • 2.  Re: I have a Brocade ICX 7450-48F with a 1G connection to my Cisco 3560 but the trunk is flapping

    Community Manager
    Posted Feb 05, 2019 10:46 AM

    @Tenmujin 

     

    ICX Switch line was acquired by Ruckus, please post your question on the Ruckus Community

    for immediate assistance.

     

    Thank you

     

    Jason

    Community Manager


    #icx
    #TheWaterCooler