Setting the Disconnect Precedence

ExtremeSwitching X450-G2, X460-G2, 5420, and 5520 PoE series switches only.

Note

Note

The switch generates an SNMP event if a PD goes offline, and the port‘s state moves from Power to Searching. You must configure SNMP to generate this event.

When the actual power used by the PDs on a switch or slot exceeds the power budgeted for that switch or slot, the switch refuses power to PDs. There are two methods used by the switch to refuse power to PDs, and whichever method is in place applies to all PoE slots in the switch. This is called the disconnect precedence method, and you configure one method for the entire switch.

The available disconnect precedence methods are:
  • Deny port
  • Lowest priority
The default value is deny port. Using this method, the switch simply denies power to the next PD requesting power from the slot, regardless of that port‘s PoE priority or port number.
Note

Note

Starting with ExtremeXOS 30.2, on ExtremeSwitching X465 and X620 series switches, priority of the port is given preference even though the disconnect precedence is deny port.

Using the lowest priority method of disconnect precedence, the switch disconnects the PDs connected to ports configured with lower PoE priorities (for information about port priorities, see Configuring the PoE Port Priority).

When several ports have the same PoE priority, the lower port numbers have higher PoE priorities. That is, the switch withdraws power (or disconnects) those ports with the highest port number(s).

The system keeps dropping ports, using the algorithm you selected with the disconnect ports command, until the measured inline power for the slot is lower than the reserved inline power.