Orange Pi Zero H2+ Status LED

[Graham]

Hi,

Firstly my thanks to the team for an outstanding job on ARMbian. I'm relatively new to this particular flavour, using it on my Orange Pi H2+ board with a few different builds under my belt now. Recently I have been having some troubles getting Pi-hole to work on the little Orange Pi board. Twice I have had it up and running perfectly, with full DNS and DHCP control of my home network, accommodating about 10 devices. However after about 6 - 12 hours of operation, they ceased to function. First time around I was not home to witness it, but when I returned later, the Allwinner chip was running pretty warm (around 60 degrees C core temp) and non-responsive, even to serial login. The board refused to boot too, and I ended up doing a full ARMbian / Pi-hole rebuild. Second time however when it did fail, the web (Pi-hole server) access seemed to not update etc. but the board appeared to still be running as DHCP was still covered just fine on the network.

 

On reboot, I saw for the first time a red flashing LED. To be honest, I never even knew this was there until now. I did some research, and it appears that for other SBC's at least, this is a status indicator, and it is used to indicated a power supply fault. The manufacturers of the Orange Pi state this is a Status LED, but apart from that I can find no other information. It is connected to GPIO15 as I recall, so really it's under the control of ARMbian. So what does the red Status LED indicate if it starts flashing? Is there a flashing code (eg 1 flash per second = power problem, 2 flashes = stack overflow, whatever).

 

I now have a 'scope monitoring the power line, and I'm going to do some closer analysis of power quality first, along with another fresh ARMbian rebuild. Unfortunately I think this time around the Ethernet port access circuitry may have been damaged, as I am no longer able to get the existing ARMbian build to access the network at all, whether set with DHCP or a static address. Back to using my Linksys router as DHCP server for the time being. I'll know later for sure (this evening) whether or not the board is damaged (assuming of course this is a power problem).

 

The last few days have been exceptionally hot here, however the core never went above about 58 degrees C, but high ambient temperature was no doubt a contributing factor to my problems. I have a heatsink on the Allwinner device, but was trying to see if I can get away with a fanless build, which should be possible given the processing requirements of Pi-hole. The board is near idle most of the time.

 

I realize this question is somewhat verbose, I'm hoping that it helps other people with similar problems/questions, or they may have some answers for me too.

[guidol]

2 hours ago, Graham said:

Recently I have been having some troubles getting Pi-hole to work on the little Orange Pi board.

Twice I have had it up and running perfectly, with full DNS and DHCP control of my home network, accommodating about 10 devices.

First time around I was not home to witness it, but when I returned later, the Allwinner chip was running pretty warm...

 

On reboot, I saw for the first time a red flashing LED.

I'll know later for sure (this evening) whether or not the board is damaged (assuming of course this is a power problem).

 

I have a heatsink on the Allwinner device, but was trying to see if I can get away with a fanless build, which should be possible given the processing requirements of Pi-hole. The board is near idle most of the time.

 

Iam running pi-hole on a Orange Pi one with legacy kernel since months 24/7 at around 46 degree celsius without problems (not using as a DHCP-Server) for about 20-30 devices (including amazon alexa and Google Home) without problems in the original crystal Acryl-case from OrangePi (but with the top open).

Which case do you use for the OPi Zero (H2+)?

All my Pi does have a small passive metalic or ceramic heatsink.

My Orange Pi Zero with mainline-kernel is running 10 degree (=59) cooler than the Orange Pi Zero with legacy kernel (up to 69) in their black cube case.
But my room temperatur is about 20 degree.

I had only one day where my OPi Zero with mainline-kernel did run very hot, but after a reboot everything was OK - and since this day no problems.
The mainline OPi Zero is running a node.sj/Node-Red with Node-Red Dashboard - so it isnt completely idle.

 

60 degree is almost normal for a OPi Zero - so firstly check your power supply and the state of the uSD-card.

 

The flashing LED is no power-supply problem, because armbian let the LED blink as a heartbeat of the system.  

 

 

[Graham]

I am running it without any case at the moment, so quoted ambient temperature is the actual ambient air temperature around the board (about 26 degrees with moderately high humidity on some days). According to ARMbianmonitor and Pi-hole, temperature definitely never went over 60 degrees at the core. I confirmed by checking the tracking or trend data in ARMbianmonitor as well.

 

I am using some little Aluminium heatsinks that I purchased off Aliexpress, and these work quite well.

 

When I say an LED is flashing, I am referring to the RED LED. This LED usually never comes on, only the green one, which is why I had never seen it before. Suddenly, when my board starting having issues, the RED LED started flashing, but I still do not know what this means. I have been unable to find suitable documentation covering this LED, aside from the Orange Pi manufacturers stating it is a status LED.

 

At this point I can only think it is my power supply, given it's cheap nature. This has not been evident on my Oscilloscope though, but with that said, I only left the scope monitoring for any sags or surges for a few hours, and the ambient temperature was closer to 24 degrees. More testing is required.

[guidol]

43 minutes ago, Graham said:

When I say an LED is flashing, I am referring to the RED LED. This LED usually never comes on, only the green one, which is why I had never seen it before. Suddenly, when my board starting having issues, the RED LED started flashing, but I still do not know what this means. I have been unable to find suitable documentation covering this LED, aside from the Orange Pi manufacturers stating it is a status LED.

 

 

Well - the LEDs are not statically defined, because you can define their usage by yourself - and the OS can have another default funtion like on a other OS (Orange Pi original Linux <--> armbian)
 

Your could find the available LEDs here:
root@pihole:~# ls -l /sys/class/leds
total 0
lrwxrwxrwx 1 root root 0 Jan  1  1970 green_led -> ../../devices/platform/leds-gpio/leds/green_led
lrwxrwxrwx 1 root root 0 Jan  1  1970 red_led -> ../../devices/platform/leds-gpio/leds/red_led
 

and which function is assigned to the LED you could find out while do a "more" an their trigger-file:

root@pihole:~# more /sys/class/leds/red_led/trigger
none mmc0 mmc1 timer [heartbeat] backlight default-on
 

here you could see I assigned the funtion [heartbeat] to the red LED

 

I did this in the /etc/rc.local with the following command (before the line with "exit 0") :
echo "heartbeat" > /sys/class/leds/red_led/trigger

 

heartbeat is this flashing LED - showing the system is running

 

mmc0 will be like a HDD-LED for your uSD-Card:

echo "mmc0" > /sys/class/leds/green_led/trigger

 

The names of your LEDs may varies.
 

[Graham]

Thanks for your assistance guidol. much appreciated.