AP PoE Issues

Power over Ethernet (PoE) issues can manifest in various ways, ranging from an AP failing to power on to intermittent reboots or connectivity loss. These symptoms often point to underlying problems in the switch configuration, AP power negotiation, or physical cabling. Diagnosing PoE issues requires a layered approach—starting from the physical layer and progressing through switch and AP configurations.
Symptoms of AP PoE issues may include:
  • AP degraded performance.
  • The AP does not power on.
  • AP reboots intermittently.
  • LED indicators are off or show fault states.
  • The controller reports AP as offline.
The following are potential root causes for AP PoE issues:
  • Insufficient PoE budget on the switch.
  • Incorrect PoE class or limit configuration.
  • Faulty cabling or connectors.
  • Environmental factors (for example, long cable runs or interference).
  • The AP model requires PoE+ (IEEE 802.3at) but is using PoE (IEEE 802.3af).

Diagnosing AP PoE Issues

Complete the following steps to gather the information required to understand the cause of the issue.

  1. Verify Cable Integrity. To confirm the physical health of the Ethernet cable connected to the ICX switch, use the built-in Time Domain Reflectometry (TDR) diagnostics.
    1. From the ICX CLI, in privileged EXEC mode, clear previous diagnostics by entering command clear cable-diagnostics tdr port-number.
    2. From the ICX CLI, in privileged EXEC mode, enter the command phy cable-diagnostics tdr port-number.
      This initiates a diagnostic test on the port.
    3. After the test completes, display the results using show cable-diagnostics tdr port-number.
      The output will show the status of each wire pair (A–D), including whether they are:
      • terminated – properly connected and functioning
      • open or short – indicating a fault
      • unknown – no signal detected, possibly due to unused pairs or negotiation issues
    Note: Before running a test, it's recommended to clear any previous diagnostics with the command clear cable-diagnostics tdr port-number.
    The following example shows how to run a diagnostic on port 1/1/2:
    device# clear cable-diagnostics tdr 1/1/2
    device# phy cable-diagnostics tdr 1/1/2
    device# show cable-diagnostics tdr 1/1/2
    
    Port    Speed   Local pair      Remote pair     Pair status
    ----    -----   ----------      -----------     -----------
    1/1/2     1G    Pair A          Pair B          terminated
                    Pair B          Pair A          terminated
                    Pair C          Pair D          terminated
                    Pair D          Pair C          terminated
  2. Verify PoE status and budget on the switch. To ensure the connected access point (AP) is receiving adequate power, verify the Power over Ethernet (PoE) status and budget allocation on the ICX switch.
    1. Check the power budget. From the ICX CLI, in privileged EXEC mode, enter show inline power.

      This command displays the total power capacity and the current available budget. Compare the following values:

      • Power Capacity Total – The maximum power the switch can deliver.
      • Current Free – The remaining power available for allocation.

      The switch must have sufficient budget to fulfill the power requirements of all connected APs.

    2. Inspect port-level PoE status. Review the following CLI output columns for the port servicing the AP:
      • Admin State: Indicates PoE is enabled administratively.
      • Oper State: Confirms PoE is actively supplying power.
      • PD Class: Must match or exceed the AP's power class.
      • Fault/Error: No faults should be present.
    In the following example, port 1/1/15 is actively supplying power to a Class 4 AP, with no faults reported:
    device# show inline power
    
    Power Capacity:         Total is 370000 mWatts. Current Free is 340468 mWatts.
    
    Power Allocations: Requests Honored 25 times
    
    
     Port   Admin   Oper    ---Power(mWatts)---  PD Type  PD Class     Pri  Fault/
            State   State   Consumed  Allocated                             Error
    -----------------------------------------------------------------------------
      1/1/1 On      Off            0         0   n/a      n/a            3  n/a
      1/1/2 On      Off            0         0   n/a      n/a            3  n/a
      1/1/3 On      Off            0         0   n/a      n/a            3  n/a
      1/1/4 On      Off            0         0   n/a      n/a            3  n/a
      1/1/5 On      Off            0         0   n/a      n/a            3  n/a
      1/1/6 On      Off            0         0   n/a      n/a            3  n/a
      1/1/7 On      Off            0         0   n/a      n/a            3  n/a
      1/1/8 On      Off            0         0   n/a      n/a            3  n/a
      1/1/9 On      Off            0         0   n/a      n/a            3  n/a
     1/1/10 On      Off            0         0   n/a      n/a            3  n/a
     1/1/11 On      Off            0         0   n/a      n/a            3  n/a
     1/1/12 On      Off            0         0   n/a      n/a            3  n/a
     1/1/13 On      Non-PD         0         0   n/a      n/a            3  n/a
     1/1/14 On      Off            0         0   n/a      n/a            3  n/a
     1/1/15 On      On         10000     29532   2P-IEEE  Class 4        3  n/a
     1/1/16 On      Off            0         0   n/a      n/a            3  n/a
     1/1/17 On      Off            0         0   n/a      n/a            3  n/a
     1/1/18 On      Off            0         0   n/a      n/a            3  n/a
     1/1/19 On      Off            0         0   n/a      n/a            3  n/a
     1/1/20 On      Off            0         0   n/a      n/a            3  n/a
     1/1/21 On      Off            0         0   n/a      n/a            3  n/a
     1/1/22 On      Off            0         0   n/a      n/a            3  n/a
     1/1/23 On      Off            0         0   n/a      n/a            3  n/a
     1/1/24 On      Non-PD         0         0   n/a      n/a            3  n/a
    -----------------------------------------------------------------------------
     Total                     10000      29532
    PoE Operation Statuses in the Switch Port lists the different operation statuses seen in the output of the show inline power command and their meaning:

    PoE Operation Statuses in the Switch Port

    Oper State Reason Action
    On Port is supplying power to a valid PD No action needed; PoE is operating as expected.
    Off Port is not supplying power Verify if a PoE device is connected and requires power.
    Denied Power budget exceeded Reallocate power or reduce load on other ports.
    Overload Excessive draw or misconfigured class Adjust AP power settings or configure a higher class.
    Non-PD Device does not support PoE No action needed unless PoE is expected.
  3. Check the configured AP power mode via the AP CLI. To verify the power mode and consumption status of the AP, connect to the AP via CLI and run the following commands.
    1. Enter the get eth command to list the available Ethernet interfaces and their operational states.
      rkscli: get eth
      
      Port  Interface  802.1X  Logical Link  Physical Link      Label
      -----------------------------------------------------------------
      0     eth0       None    Down          Down               10/100/1000
      1     eth1       None    Up            Up 1000Mbps full   100/1000/2500/5000/10000 PoE
      
      Note: Read Port#N as N+1, if you are referring this CLI output with AP's "Configure :: Ethernet Ports" UI Page.
      OK
      Note: When comparing this CLI output with the AP Ethernet port configuration in the controller web UI page, read the Port numbers as N+1 (for example, Port 0 in the CLI output is Port 1 in the web UI).
    2. Enter the get power-mode command to display the currently configured PoE mode as well as the power consumption status.
      rkscli: get power-mode
      PoE Configured Mode      : Auto
      Power Consumption Status : 802.3at Switch/Injector
      USB Status               : Disabled
      OK
  4. Review the AP Support Log. This file contains various sections relevant to PoE as listed:
    • PoE Mode: If the AP is set to Auto, it will request the maximum supported power. Misconfiguration can lead to insufficient power and disabled features.
      ### PoE Mode ###
      PoE Configured Mode      : Auto
      Power Consumption Status : 802.3at Switch/Injector
      USB Status               : Disabled
    • LLDP Information: LLDP ensures the AP communicates its power requirements to the switch. If LLDP is disabled or misconfigured, the AP may not receive adequate power.
      ### LLDP Info ###
      LLDP version: 1.0.15
      LLDP state: Enabled
      LLDP interval: 30
      LLDP holdtime: 120
      LLDP mgmt: Enabled
      LLDP poe: Enabled     ------------------------------> PoE is advertised through LLDP
      LLDP power: 40000     ------------------------------> advertised power requirement
      <truncated output>
      -------------------------------------------------------------------------------
      LLDP neighbors:
      -------------------------------------------------------------------------------
      Interface:    eth1, via: LLDP, RID: 3, Time: 4 days, 04:37:58
        Chassis:     
          ChassisID:    mac 60:9c:9f:bc:26:6c
          SysName:      Tpubs_LAB-7150-2
          SysDescr:     Ruckus Wireless, Inc. ICX7150-24-POE, ---------> indicates system capabilities of the neighbor 
      <truncated output>

Resolving AP PoE Issues

The following resolution steps can help you manage the power budget on an ICX switch and meet the PoE requirements of connected APs:

  1. On the ICX switch, assign higher priority to critical AP ports when the switch power budget is limited.
    device(config)# interface ethernet 1/1/2
    device(config-if-e1000-1/1/2)# inline power priority 1

    This ensures that port 1/1/2 receives power before lower-priority ports during budget constraints.

  2. Allocate power based on the AP’s IEEE class to ensure sufficient resources are assigned where needed.
    device(config)# interface ethernet 1/1/2
    device(config-if-e1000-1/1/2)# inline power power-by-class 4

    This ensures that port 1/1/2 provides up to 30W of power to a Class 4 device (note the minimum output power after the cable loss is 25.5W).

  3. Set a maximum power limit for specific ports to prevent overconsumption.
    device(config)# interface ethernet 1/1/2
    device(config-if-e1000-1/1/2)# inline power power-limit 11000

    This ensures that port 1/1/2 does not consume more than 11,000 milliwatts.

  4. Use the AP CLI to configure the desired PoE mode.
    rkscli: set power-mode at
    WARNING:Functionality will be limited in 802.3at PoE mode
    OK

    This ensures the AP requests sufficient power from the switch or injector.