Dell PowerConnect 6248 LAG Dropping Connection

Netzwerk Switch

Netzwerk Switch
A description has not yet been added to this group.

Dell PowerConnect 6248 LAG Dropping Connection

This question is not answered

We are currently having some issues with our Blade Server LAG connection. The error we receive is "0/3/1 is transitioned from the Forwarding state to the Blocking state in instance 0". This happens and then the connection will drop as the connections transition from forwarding to learning states. This happens a few times per day.

Connection Information:

  • We are not using Jumbo Frames for our connection to the blade servers
  • Portfast is not enabled.
  • Firmware is currently on and the latest is
  • There is a high number of Broadcast, Multicast and Unicast Packets on the LAG Channel.

Do you have any suggestions for a fix?

Thanks in advance

All Replies
  • Hi,

    How is it configured? Switching between forwarding and blocking sounds like something is causing it think there is a spanning tree change. Updating the firmware would also be a good idea. 

  • Hi Josh,

    thanks for your reply. The switch is configured as so:

    Spanning Tree Is Enabled
    Rapid STP
    Port Fast Is Disabled
    Priority is default at 32768

    STP on the LAG is Enabled,
    Port Fast Disabled

    Do you need any more information?

    My current thinking is to upgrade the firmware and then enable Port Fast on the LAG.


  • If this LAG connects one switch to another switch, it is not recommended to enable portfast.

    Can you provide us with some more information on the topology you are working with?

    - What blade chassis is the server installed in?

    - What model server?

    - What model switch is installed in the blade chassis?

    - Is this error being seen on the 6248 or the blade chassis switch?

    - Is port 0/3/1 the only interface with this message?

    - What does port 0/3/1 connect to?

    These transitions are typically caused by spanning tree topology changes or faulty cables/ports. Do you have a spare cable you can try? An open port on the switch that can be tested?