Ethernet uplink speed degraded and Low power mode unplanned

EnriqueFigueroa
Conversationalist

Ethernet uplink speed degraded and Low power mode unplanned

Hi,
For the past 2 months, we have been experiencing a problem with the message “Ethernet uplink speed degraded” and “Low power mode unplanned”. Below are the tests performed and the status of the situation:

 

1. Verification of
Physical connection Wiring connection verified:
Cable length: 50 meters (OK)
Cable type: Jack no. 6 (OK)
Cable pins: Correct (OK)

2. Cisco 2960 PoE 15.4 W PoE switch Checked: Reset switch (OK)
Reset switch (OK)
Interfaces rebooted (OK)
Switch IOS upgraded (OK)
Verified the physical ports of the switch (OK)
Tested with another 15.4W PoE switch (OK)

3. Configuration
CDP/LLDP CDP/LLDP enabled and configured on switch and interface (OK)
Auto-negotiation (OK)
Full duplex between switch and AP (OK)
100 Mbps speed (OK)
Correct configuration of the interface, the switch and the AP (OK)

4. Physical status of the AP and switch
Verified full physical status of both AP and switch (OK)

5. Exhaustive tests performed
Despite exhaustive testing of the equipment, the problem persists and the messages continue to appear.

6. Remarks
It is worth mentioning that the AP antennas are still working properly, but the messages indicate otherwise.

 

The problem started about 2 months ago, coinciding with Cisco Meraki updates to your control panel.
Despite our best efforts and thorough verification of all elements involved, the problem persists. We remain available for further testing or recommendations to resolve the incident based on the community. 😁

13 Replies 13
Mloraditch
A model citizen

So you haven't provided what the AP is reporting for speed-duplex or power, nor the exact model of the switch or the AP. 

 

It appears for speed you may be only getting 100mbps? If so that would be a degraded uplink for any current AP models. Additionally if your switch is just a plain 2960 and not an X model it would only support 802.3af power, and current AP models need at least 802.3at. Even if you do have a 2960X, depending on PoE consumption you may not get the correct power amount and you may have to manually adjust your inline power commands.

These alerts were somewhat recently added to call out these issues more prominently, so you may have had the problem for quite a while.

EnriqueFigueroa
Conversationalist

We used MR42 antennas and Cisco 2960 switches with 802.3af PoE support. Our access points always operated in “Low Power Mode”, which is normal and expected. In this state, the APs showed as “healthy” on the console, with a green indicator. The only difference was that some functions were disabled due to low power consumption.

 

https://documentation.meraki.com/MR/Monitoring_and_Reporting/Low_Power_Mode

Mloraditch
A model citizen

I would say they could possibly word it better for the models that support it vis-a-vis low power, but your best bet is to open a case or make a wish to draw visibility to it.

 

They've decided to move the info from something that's visible to an alert, probably to help decrease support cases as a result of those issues. 

EnriqueFigueroa
Conversationalist

I don't think it is what you mention, cisco support mentions that it is possible to work with 2960 802.3af switch, but for upgrade concept its minimum is PoE+.

Mloraditch
A model citizen

Yes it does work, but it is degraded performance and doubly so by being only 100mbps, its definitely not recommended. You may disagree whether it's noteworthy as an alert status, but it's not inaccurate.

EnriqueFigueroa
Conversationalist

Ok, bro thanks

CDUNK
Conversationalist

Give "power inline static" on the switch interface configuration a shot?

  • static —Enables powered-device detection. Pre-allocate (reserve) power for a port before the device discovers the powered device. The device reserves power for this port even when no device is connected and guarantees that power will be provided upon device detection.

EnriqueFigueroa
Conversationalist

I have tried the PoE settings but it still does not work.

VivekT
Conversationalist

Did you try external power injector ? That might make a diffrence here.

EnriqueFigueroa
Conversationalist

Yes, I tried it a while ago. unfortunately it doesn't work either, and I find it strange that the dashboard still says it's on low power or degraded, the injector is 56v - 0.55A.

VivekT
Conversationalist

Now ,I only say if you can try  Meraki devices .Please connect the AP on Meraki sw/ Meraki FW  If that also does not work that could be some bug in firmware.

TAC can help you on this.

julioleal
Here to help

I opened a Meraki TAC, but they didn't help me much with that.

"Please start by performing a cable test, checking the negotiation settings on the switch, and potentially cycling the switch ports."

 

 

I have around 400 APs on several different networks, connected to several different switches, but I've noticed that all the APs that are connected to 100mbit are showing the degradation alert.

I did a test with any AP near me, where it was connected to a meraki switch and the cabling was ok, it wasn't showing any error alerts. I forced the port where the AP is connected and mysteriously the alert appears simply because the AP is connected to a 100 Mbit port (forced), after which I did a cable test on the meraki where all the tests were completed successfully.

I sent this to the meraki engineer and his reply was simply “I do not see any issues with the Port or AP. I will move this case to closed as proper investigation needs to occur through the before mentioned checks.”

And closed ticket.

Júlio César de Sousa Leal
julioleal
Here to help

I believe the problem is with the Meraki cloud. Earlier, in the same call, the engineer said this: “We had a recent issue which alerted for the same:

"Ethernet uplink speed degraded" error, but that was due to an alerting issue and the engineering team disabled the alert for all customers. The alert is now enabled and contains fixes to properly alert. The reason you see the alerts across multiple sites is because the alert was disabled, which may have hidden valid alerts, and now those alerts are properly shown. The next step is to investigate the physical layer or negotiation settings."

Júlio César de Sousa Leal
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