HP Virtual Connect Version 3.61 Release Notes

Appendix: Feature details 20
When server ports are disabled because of a pause flood occurrence, a minor warning icon is displayed.
Hover your mouse over the icon to display the following tooltip.
Configuring pause flood protection settings
To enable pause flood protection, use the set port-protect command:
set port-protect [-quiet] [networkLoop=<Enabled|Disabled>]
[pauseFlood=<Enabled|Disabled>]
To reset all ports disabled due to the port protection action, use the reset port-protect command:
>reset port-protect
Ethernet switch interfaces use pause frame based flow control mechanisms to control data flow. When a
pause frame is received on a flow control enabled interface, the transmit operation is stopped for the pause
duration specified in the pause frame. All other frames destined for this interface are queued up. If another
pause frame is received before the previous pause timer expires, the pause timer is refreshed to the new
pause duration value. If a steady stream of pause frames is received for extended periods of time, the transmit
queue for that interface continues to grow until all queuing resources are exhausted. This condition severely
impacts the switch operation on other interfaces. In addition, all protocol operations on the switch are
impacted because of the inability to transmit protocol frames. Both port pause and priority-based pause
frames can cause the same resource exhaustion condition.
VC provides the ability to monitor server downlink ports for pause flood conditions and take protective action
by disabling the port. The default polling interval is 10 seconds and is not customer configurable. VC
provides system logs and SNMP traps for events related to pause flood detection.
This feature operates at the physical port level. When a pause flood condition is detected on a Flex-10
physical port, all Flex-10 logical ports associated with physical ports are disabled.