How Does The Switch Prioritize Power Allocations - HP ProCurve 2626-PWR Manual Supplement

General PoE Operation
Table 2. Example of PoE Priority Operation
Port Priority
Setting
25 - 48 Critical
9 - 12 High
1 - 8 Low
13 - 24 - n/a -
1
For a listing of PoE configuration commands, with descriptions, refer to "Configuring PoE Operation" on page 7.
2
In the default PoE configuration, the ports are already set to the low priority. In this case, the command is not necessary.
6
How Does the Switch Prioritize Power Allocations? The switch simul­
taneously uses two priority methods:
The priority class method enables port PoE priority class assign­
■
ments of Low (the default), High, and Critical.
■ The port-number priority method gives a lower-numbered port
priority over a higher-numbered port within the same configured
priority class.
Suppose, for example, that you configure PoE priority as shown in table 2.
1
Configuration Command
This priority class always receives power. If there is not enough power to provision PDs on
all of the ports configured for this class, then no power goes to ports configured for High and
Low priority. If there is enough power to provision PDs on only some of the "Critical" ports,
then power is allocated to the "Critical" ports in ascending order, beginning with the lowest-
numbered port in the class, which, in this case, is port 25. For this example, the CLI command
to set ports to "Critical" is:
HPswitch(config)# interface e 25-48 power critical
This priority class receives power only if all PDs on ports with a Critical priority setting are
receiving full power. If there is not enough power to provision PDs on all ports with a High
priority, then no power goes to ports with a Low priority. If there is enough power to provision
PDs on only some of the "High" ports, then power is allocated to the "High" ports in ascending
order, beginning, in this example, with port 9, until all available power is in use. For this
example, the CLI command to set ports to "High" is:
HPswitch(config)# interface e 9-12 power high
This priority class receives power only if all PDs on ports with High and Critical priority
settings are receiving power. If there is enough power to provision PDs on only some Low
priority ports, then power is allocated to the ports in ascending order, beginning with the
lowest-numbered port in the class (port 1, in this case), until all available power is in use. For
this example, the CLI command to set ports to "Low"
HPswitch(config)# interface e 1-8 power low
For this example, PoE is disabled on these ports. The CLI command for this setting is:
HPswitch(config)# no interface e 13-24 power
and Resulting Operation
2
is: