Power over Ethernet | 787
Related Configuration Tasks
• Manage Ports using Power Priority and the Power Budget on page 789
• Monitor the Power Budget on page 792
• Manage Power Priorities on page 792
• Recover from a Failed Power Supply on page 793
• Power Additional PoE Ports on the S-Series on page 794
Enabling PoE on a Port
PoE is disabled by default. Enable PoE on a port from INTERFACE mode using the command
power inline {auto [max_milliwatts] | static [max_milliwatts]}.
• The
power inline auto command allows the port to determine the amount of power that a connected
Class 1–4 powered device requires, and supply it. See Table 36-1 on page 785.
• The
power inline static command without the qualifier guarantees 15.4W to the powered device.
• You can limit the maximum amount of power (in milliwatts) available to a powered device with the
command
power inline auto max_milliwatts or with power inline static max_milliwatts
• Disable PoE on a port using the no power inline command.
Ports configured with
power inline auto have a lower priority for access to power than those configured
with
power inline static. As a second layer of priority setting, use the [no] power inline priority command.
Use the
power inline static max_milliwatts command to avoid allocating more power than necessary to a
port because allocated power is made unavailable to other ports regardless of whether it is consumed.
Typical IP phones use 3-10 Watts.
Figure 36-1. Enabling PoE
0/1
1/0
1/1
R1(conf)# int range gi 1/1
R1(conf-if-gi-1/1)# power inline auto
R1(conf)# int range gi 0/1
R1(conf-if-gi-0/1)# power inline static
R1(conf)# int range gi 1/0
R1(conf-if-gi-1/0)# power inline auto 4000