PowerScale: The management (bge0) interface should be used for SSH only.

The 1G mgmt interface on Generation 6 hardware is designed to handle ssh traffic. It does not support TCP Segmentation Offload (TSO). This can cause the interface to flap when exposed to a moderate to heavy workload.

If there is noticeable port flapping on MGMT-1 interfaces, also check for watchdog resets for bge interfaces in messages logs.  

The reset looks like this:

2018-05-22T09:24:12-05:00 <0.7> isilon-3 /boot/kernel.amd64/kernel: bge0: watchdog timeout -- resetting

The mgmt interface does not support TSO, all segmentation is passed to the CPU for processing.

1. Unplug the 1G interfaces and use 10G for both management and data pools.
   1. This method is recommended first because it introduces no caveats. 
   2. See "Notes" for this action plan if the interface is already configured.
2. Create a management pool for SSH assigned to the 1G interfaces. Then create a management pool for WebUI and data pools for all other traffic, assign the 10G interfaces to these pools.
   • This method requires the following conditions:
   1. All subnets must have a unique gateway priority. Support recommends using 10 as the highest priority, and going up by 10 for each lower priority. (that is: 10,20,30,40, and so on)
   2. The highest priority subnet must include the WebUI management pool.
   3. The SSH pool must be part of the System Access Zone.

1. If the 10G switch can see the same network as the 1G switch:
   1. Add a 10G interface to the management pool.
   2. Verify that the cluster can be reached over the IP assigned to the 10G interface.
   3. Add the remaining 10G interfaces to the management pool.
   4. Remove a single 1G interface. This is ideal from Node 2 or above.
   5. Verify that the IP for that node is reachable over the 10G with the 1G removed.
   6. Remove the remaining 1G interfaces.
   7. Test all nodes to verify that the WebUI and SSH work for all management pool addresses.
2. If the 10G switch cannot access the management subnet. There are two options in this case:
   1. Create a new subnet for management on the 10G switch.
   2. Work with the networking team to add the vlan/subnet to the 10G switch. (then follow the steps above)