Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

Navigation

Example: Configuring PoE Interfaces with Different Priorities on an EX Series Switch

Power over Ethernet (PoE) ports supply electric power over the same ports that are used to connect network devices. These ports allow you to plug in devices that need both network connectivity and electric power, such as voice over IP (VoIP) phones, wireless access points, and some IP cameras.

By default, PoE ports on EX Series switches are set to low power priority. You can configure a PoE port to have a high power priority setting. If a situation arises where there is not sufficient power for all the PoE ports, the available power is directed to the higher priority ports, while power to the lower priority ports is shut down as needed. Thus you should set ports that connect to security cameras, emergency phones, and other high priority powered devices to high priority.

This example describes how to configure a few high priority PoE interfaces.

Requirements

This example uses the following software and hardware components:

  • Junos OS Release 9.0 or later for EX Series switches
  • One EX Series switch that supports PoE

Before you configure PoE, be sure you have:

Overview and Topology

The topology used in this example consists of a switch that has 24 ports. Eight of the ports support PoE (IEEE 802.3af), which means they provide both network connectivity and electric power for powered devices such as VoIP telephones, wireless access points, and IP security cameras that require 12.95 W or less. The remaining 16 ports provide only network connectivity. You use the standard ports to connect devices that have their own power sources, such as desktop and laptop computers, printers, and servers. Table 1 details the topology used in this configuration example.

Table 1: Components of the PoE Configuration Topology

PropertySettings

Switch hardware

Switch with 24 Gigabit Ethernet ports: 8 PoE interfaces (ge-0/0/0 through ge-0/0/7) and 16 non-PoE interfaces (ge-0/0/8 through ge-0/0/23)

VLAN name

default

Connection to a wireless access point (requires PoE)

ge-0/0/0

Security IP Cameras (require PoE)

ge-0/0/1 and ge-0/0/2 high

Emergency VoIP phone (requires PoE)

ge-0/0/3 high

VoIP phone in Executive Office (requires PoE)

ge-0/0/4 high

Other VoIP phones (require PoE)

ge-0/0/5 through ge-0/0/7

Direct connections to desktop PCs, file servers, integrated printer/fax/copier machines (no PoE required)

ge-0/0/8 through ge-0/0/20

Unused ports (for future expansion)

ge-0/0/21 through ge-0/0/23

Configuration

To configure PoE interfaces:

CLI Quick Configuration

By default, PoE interfaces are created for all PoE ports and PoE is enabled. The default priority for PoE interfaces is low.

To quickly set some interfaces to high priority and to include descriptions of the interfaces, copy the following commands and paste them into the switch terminal window:

[edit]

set poe interface ge-0/0/1 priority high telemetries
set poe interface ge-0/0/2 priority high telemetries
set poe interface ge-0/0/3 priority high telemetries
set poe interface ge-0/0/4 priority high telemetries

set interfaces ge-0/0/0 description "wireless access point"
set interfaces ge-0/0/1 description "security camera front door"
set interfaces ge-0/0/2 description "security camera back door"
set interfaces ge-0/0/3 description "emergency phone"
set interfaces ge-0/0/4 description "Executive Office VoIP phone"
set interfaces ge-0/0/5 description "staff VoIP phone"
set interfaces ge-0/0/6 description "staff VoIP phone"
set interfaces ge-0/0/7 description "staff VoIP phone"

Step-by-Step Procedure

To configure PoE interfaces with different priorities:

  1. Set the interfaces connected to high priority powered devices to high priority. Include the telemetries statement for the high priority interfaces, thus enabling the logging of power consumption on those interfaces:
    [edit poe]
    user@switch# set interface ge-0/0/1 priority high telemetries
    user@switch# set interface ge-0/0/2 priority high telemetries
    user@switch# set interface ge-0/0/3 priority high telemetries
    user@switch# set interface ge-0/0/4 priority high telemetries
  2. Provide descriptions for the PoE interfaces:
    [edit interfaces]
    user@switch# set ge-0/0/0 description "wireless access point"
    user@switch# set ge-0/0/1 description "security camera front door"
    user@switch# set ge-0/0/2 description "security camera back door"
    user@switch# set ge-0/0/3 description "emergency phone"
    user@switch# set ge-0/0/4 description "Executive Office VoIP phone"
    user@switch# set ge-0/0/5 description "staff VoIP phone"
    user@switch# set ge-0/0/6 description "staff VoIP phone"
    user@switch# set ge-0/0/7 description "staff VoIP phone"
  3. Connect the wireless access point to interface ge-0/0/0. This interface uses the default PoE settings.
  4. Connect the two security cameras to interfaces ge-0/0/1 and ge-0/0/2. These interfaces are set to high priority with telemetries enabled.
  5. Connect the emergency VoIP phone to interface ge-0/0/3. This interface is set to high priority with telemetries enabled.
  6. Connect the Executive Office VoIP phone to interface ge-0/0/4. This interface is set to high priority with telemetries enabled.
  7. Connect the staff VoIP phones to ge-0/0/5, ge-0/0/6, and ge-0/0/7. These interfaces use the default PoE settings.

Results

Check the results of the configuration:

[edit]
user@switch# show
interfaces { ge-0/0/0 { description "wireless access point"; unit 0 { family ethernet-switching; } } ge-0/0/1 { description "security camera front door"; unit 0 { family ethernet-switching; } } ge-0/0/2 { description "security camera back door"; unit 0 { family ethernet-switching; } } ge-0/0/3 { description "emergency phone"; unit 0 { family ethernet-switching; } } ge-0/0/4 { description "Executive Office VoIP phone"; unit 0 { family ethernet-switching; } } ge-0/0/5 { description "staff VoIP phone"; unit 0 { family ethernet-switching; } } ge-0/0/6 { description "staff VoIP phone"; unit 0 { family ethernet-switching; } } ge-0/0/7 { description "staff VoIP phone"; unit 0 { family ethernet-switching; } } } poe { interface all; interface ge-0/0/1 { priority high; telemetries; } interface ge-0/0/2 { priority high; telemetries; } interface ge-0/0/3 { priority high; telemetries; } interface ge-0/0/4 { priority high; telemetries; } }

Verification

To verify that PoE interfaces have been created and are operational, perform the following tasks:

Verifying That the PoE Interfaces Have Been Created with the Correct Priorities

Purpose

Verify that the PoE interfaces on the switch are now set to the correct priority settings.

Action

List all the PoE interfaces configured on the switch:

user@switch> show poe interface
Interface Admin        Oper        Max       Priority Power             Class
          status       status      power              consumption
 ge-0/0/0 Enabled      ON          15.4W     Low      7.9W                0
 ge-0/0/1 Enabled      ON          15.4W     High     4.8W                0
 ge-0/0/2 Enabled      ON          15.4W     High     4.8W                0
 ge-0/0/3 Enabled      ON          15.4W     High     3.3W                2
 ge-0/0/4 Enabled      ON          15.4W     High     4.7W                2
 ge-0/0/5 Enabled      ON          15.4W     Low      3.2W                2
 ge-0/0/6 Enabled      ON          15.4W     Low      3.3W                2
 ge-0/0/7 Enabled      ON          15.4W     Low      3.3W                2

Meaning

The show poe interface command lists PoE interfaces configured on the switch, with their status, priority, power consumption, and class. This output shows that eight PoE interfaces are enabled. Interfaces ge-0/0/1 through ge-0/0/4 are configured as priority high. The remaining PoE interfaces are configured with the default priority value of low.

Published: 2012-12-07