R750 2.5G POE port limited to 55Mbps down, 94Mbps up

[Alleprt]

Running Unleashed. I have one R750 AP that produces such speeds on speed tests with power supplied through the 2.5G POE port. The speeds are quite consistent, maybe + or - 2Mbps. When I connect another R750 to this cable it produces normal speeds, close to 1Gbps down and up. POE at is manually selected in settings and the injector is definitely at, no problems with other APs. 

When I connect uplink to the other 1Gbps non-POE port and use a power adapter the speeds become normal, close to 1Gbps. So, something is limiting that POE port. I think it would be unusual if a hardware fault would limit speeds to such consistent values. Is it possible that something in the settings is limiting that particular port? I did factory reset several times without any change. That AP didn't have Unleashed initially and I cross-flashed Unleashed to it. I did the same to other 3 AP and they don't have any issues. Is it possible that some limiter was left over from another firmware and was not cleared by factory resets? Where can I look? I assume I need to use CLI.

[Mayank]

Hi Alleprt

Thank  you for reaching us

Could you please provide more details about the version currently running on your Unleashed setup ?

Thank you 

Mayank

[Alleprt]

Hi Mayank,

Thanks for responding. The Unleashed version is the latest 200.18.7.1.323.

[Mayank]

Hi Alleprt,

I have a question for you here :

Do the AP is power with full power when its on 100 Mbps? What is the LED status on the AP?

Is there any CRC error on the port connected to the AP?

Connect the R750 directly to a known-good laptop with a 2.5 Gbps NIC using the same cable and then test.

What is the speed negotiated on the switch?

Check power status in the AP GUI if its in full:

Go to Dashboard > System Info and verify Power Mode = Full

Could you help us with below output from the AP:

show ethinfo
get eth (This shows port speed, duplex, and errors.)
get power-mode(Check if it's running in full power mode.)

If errors are seen (e.g., CRC or alignment), it could be a cable or port issue.

Thanks
Mayank

[Alleprt]

Mayank, 

Thank you for replying. You showed me how to find where the problem was and still is. Cables, power injector, switch etc. are all fine because when I connect another R750 AP to the same cable I get full speeds. The switch is gigabit, then it's an at-capable passive injector, then the AP. 'at' POE is set in the AP group, so no power issues are reported and other APs work fine. 

I couldn't do 'show ethinfo' in rkscli. 'get power-mode' gives me this:
PoE Configured Mode : AT
Power Consumption Status : 802.3at Switch/Injector
USB Status : Enabled

But when I did 'get eth' I got this:

Port Interface 802.1X Logical Link Physical Link Label
-----------------------------------------------------------------
0 eth0 None Down Down 10/100/1000
1 eth1 None Up Up 100Mbps full 100/1000/2500 PoE

Note: Read Port#N as N+1, if you are referring this CLI output with AP's "Configure :: Ethernet Ports" UI Page.
OK

That '100Mbps full' is the problem. When I connect a power adapter and connect the same cable to the 1Gb non-POE port I get this:

Port Interface 802.1X Logical Link Physical Link Label
-----------------------------------------------------------------
0 eth0 None Up Up 1000Mbps full 10/100/1000
1 eth1 None Down Down 100/1000/2500 PoE

Note: Read Port#N as N+1, if you are referring this CLI output with AP's "Configure :: Ethernet Ports" UI Page.
OK

So, the 2.5Gbps port is somehow limited to 100Mbps. Just to reiterate - cables, switches etc. are not at fault because when they are connected to the other port or another AP the speeds are full. 

Do you have any idea why the POE port can be limited to 100Mbps and this limit is not removed by a factory reset? Is there any way to remove the limit?

P.S. I did 'set factory' and rebooted this AP as I remember reading that factory reset with a button may not reset all the setting. Doing this from CLI didn't change anything. Still 100Mbps. There is a command 'set ethspeed' that looks promising. I tried 'set ethspeed eth1 auto', rebooted and still 100Mbps. And I tried 'set ethspeed eth1 1000' and still 100Mbps. Help please.