[Solved] LED heartbeat stops


Using NanoPi Neo with fresh install of current download version (DietPi_v145_NanoPiNEO-armv7-(Jessie)) which has been auto updated to current version.

No software installed. SSH into device using ethernet.

Not much changed in dietpi-config - Canadian English, time zone, LEDs - and I don’t think much else.

LEDs were changed
blue_led : mmc0 │
green_led : heartbeat

After about 1/2 to 3/4 hr. the green led heart beat stops and goes constant on. Blue works as expected.

Going back into diet-config to look at settings still shows green_led : heartbeat
When I go back in menu it restarts.

What could be causing this?

Gordon Williams

Hi Gorden,

Yes, same experience after each reboot here.

Default settings
Armbian unlike older/other H3 OS images uses the green led as ‘power on’ indicator (blinking means ‘ready to login’ or ‘shutting down’), the red led (blue on NanoPis) can be used for your own purpose.

H2+ and H3 - Armbian Documentation

Would you please, when green led is light solid, show output of:

uname -a

cat /sys/class/leds/green_led/trigger

cat /sys/class/leds/green_led/brightness



A few things that I noticed when I was doing a fresh install.

  1. Dietpi download version is 145 from Feb 2017 which then get updated to 158 automatically. Armbian has had more recent releases for NanoPi since Feb and I’m wondering if there are some Armbian changes that aren’t being updated by dietpi as it goes through the auto update procedure.

  2. During the First Run.

  • The Blue light is on heartbeat green goes low to bright to flashing - then I think it reboots itself and ends up blue heartbeat and green bright.
  • Now ssh in and start update process.
  • Once update to V158 finished and rebooted Blue LED off, Green LED bright, ssh in and get to DietPi-software screen.
  • Green on
  • dietpi-config >display options> LED I haven’t selected anything but Green is now changed to Heartbeat. :open_mouth: Screen says Green Heartbeat, Blue none - leave it as is and go back and select install now with nothing to install. Goes through update and upgrade with 55 prog to upgrade.
  • during upgrade green still on heartbeat.

during upgrade
Unpacking udev (215-17+deb8u7) over (215-17+deb8u6) …
Processing triggers for systemd (215-17+deb8u6) …
Setting up udev (215-17+deb8u7) …
addgroup: The group `input’ already exists as a system group. Exiting.
update-initramfs: deferring update (trigger activated)
Processing triggers for initramfs-tools (0.120+deb8u2) …
ln: failed to create hard link ‘/boot/initrd.img-3.4.113-sun8i.dpkg-bak’ => ‘/boot/initrd.img-3.4.113-sun8i’: Operation not permitted
update-initramfs: Generating /boot/initrd.img-3.4.113-sun8i
update-initramfs: Converting to u-boot format
(Reading database … 16106 files and directories currently installed.)
Preparing to unpack …/initramfs-tools_0.120+deb8u3_all.deb …

  • reboot and after reboot green is on and not heartbeat. :thinking:

results with blue off, green supposed to be heartbeat but now on

root@DietPi:~# uname -a
Linux DietPi 3.4.113-sun8i #10 SMP PREEMPT Thu Feb 23 19:55:00 CET 2017 armv7l GNU/Linux

root@DietPi:~# cat /sys/class/leds/green_led/trigger
none mmc0 timer heartbeat backlight [default-on]

root@DietPi:~# cat /sys/class/leds/green_led/brightness

After setting Green heartbeat, blue mmc0
root@DietPi:~# cat /sys/class/leds/green_led/trigger
none mmc0 timer [heartbeat] backlight default-on

root@DietPi:~# cat /sys/class/leds/blue_led/trigger
none [mmc0] timer heartbeat backlight default-on

after reboot green heartbeat, blue mmc0 and then after a few seconds - green solid on, blue occasionally flashes for mmc0
root@DietPi:~# cat /sys/class/leds/green_led/trigger
none mmc0 timer heartbeat backlight [default-on]

root@DietPi:~# cat /sys/class/leds/blue_led/trigger
none [mmc0] timer heartbeat backlight default-on

So, something is changing the green light shortly after boot. This time it is only happening a few seconds after boot while before it was 30 -45 minutes after boot.

Any clues why this is happening? Is this a dietpi problem?

As K-plan mentioned Armbian uses the green as the power light.

After I set the green light to heartbeat after booting, it seems to stay in heartbeat mode. So it seems that on boot dietpi makes the green led change to heartbeat and then something comes along a short while later and changes it to full on.



Default settings
Armbian unlike older/other H3 OS images uses the > green led > as > ‘> power on’ indicator > (> blinking means > ‘> ready to login> ’ or ‘> shutting down> ’)> , …

H2+ and H3 - Armbian Documentation


Default settings
Armbian unlike older/other H3 OS images uses the green led …

H2+ and H3 - Armbian Documentation

DietPi | 16:31 | Fri 24/11/17
V158 | NanoPi Neo (armv7l)

Created by : Daniel Knight
Web : > http://DietPi.com

Device image possible thanks to: ARMbian

DietPi based on Armbian boot-files/kernel. It’s is “hard-coded” in 3.x initrd.img-3.4.113-sun8i / kernel.

Possible “solutions”:

  • remove “green_led” from LED Control in dietpi-config
  • setting echo heartbeat >/sys/class/leds/blue_led/trigger after ready to login blinking sequence by a time based script created by user itself. (Not update safe!)

OK, but that is not what I experience with the NanoPi Neo.

On boot, green goes ON, then Heartbeat, then ON. Changing from Heartbeat to ON has nothing to do with me logging in.

On halt, green goes ON, then Heartbeat, then dim. The heartbeat is during part of the shut down process.

Anyway, I suppose that it is just a problem with Armbian documentation.

Suggestion for Dietpi on H3 boards is that green LED light options be removed from the Dietpi-config> Display settings if it is not going to work. Having it available makes one think that other things may be going wrong and the OS stability is suspect.

I’ve changed the title to Solved.

Gordon Williams

No! Please read careful.

On boot, green goes ON, then blinking means ‘ready to login’, then ON.

On halt, green is ON, then blinking means ‘shutting down ’, then dim.

My interpretation of the Armbian doc was that it would be in the “ready to login state” until login occurred. Therefore flashing/heartbeat would continue during that period.

I understand your interpretation though. Maybe a single flash rather than a series of heartbeats would have been better to indicate the instant in time login became available (state change) rather than have them occur for a period and then stop.

Anyway, I’ll leave the green light alone.

Gordon Williams