Dietpi: How to suspend DietPi?

[tifDev]

Creating a bug report/issue

Required Information

DietPi version
VERSION_CORE=6
VERSION_SUB=30
VERSION_RC=0

Distro version: buster

When I run systemctl suspend I get this message: "Failed to connect to bus: No such file or Directory".

How can i suspend DietPi?

[Joulinar]

Hi,

many thanks for your report. What kind of SBC/device you are running?

[MichaIng]

You require dbus and systemd-logind for that:

systemctl unmask systemd-logind
apt install dbus
systemctl start systemd-logind

[Joulinar]

@MichaIng
pls correct me if I'm wrong but SBC like Raspberry Pi doesn't support any form of power management. isn't it?

[tifDev]

My device is a Raspberry Pi 4

[tifDev]

systemd start systemd-logind

When i run that i get this message: "Excess arguments."

@MichaIng

Note: I'm using Raspberry Pi 4

[MichaIng]

When i run that i get this message: "Excess arguments."

Whoopsie, the command must be systemctl, please try:

systemctl unmask systemd-logind
apt install dbus
systemctl start systemd-logind

@Joulinar
I have no idea honestly, since I never actively used them as desktop system where a suspend to RAM would be reasonable, but as server only. But as long as systemctl suspend pauses all running processes, turns off video signal and all such, the ~1W additional hardware power consumption on top of RAM only is probably not an issue?

[tifDev]

systemctl unmask systemd-logind

Failed to connect to bus: No such file or directory

Running just systemctl outputs the same message.

@MichaIng Still not working...

---

I'm also using this as a server but i don't use it during the day so i don't want my RPI to be running during the day.

[Joulinar]

Still I don't believe it's possible on RPi devices

https://raspberrypi.stackexchange.com/questions/104221/how-to-hibernate-suspend-rapberry-pi

[MichaIng]

@tifDev
Did you install dbus as well? In case start it manually (although should be done on install automatically): systemctl start dbus

However for your use-case it seems that a simple shutdown/poweroff makes more sense? Probably the missing simple power button is an issue in case of RPi?

[Joulinar]

personally I'm using power supply with power on/off button. So quite simple to switch on/off

[MichaIng]

Indeed, a socket strip with power switch, why didn't I think about this 😄.

[tifDev]

Still outputting the same error: Failed to connect to bus: No such file or directory

I believe there is no systemctl available.

Probably the missing simple power button is an issue in case of RPi?

Yes, that button would be really useful

personally I'm using power supply with power on/off button. So quite simple to switch on/off

I didn't thought about this too :smiley:
The problem is that when i shutdown the RPI via CLI the fan still keeps working but that would fix this.

[Joulinar]

Personally I'm using this case. Got it on Amazon including the power supply

https://www.amazon.de/dp/B07TYW63M8/ref=cm_sw_r_cp_apa_i_gM84EbNANWETD

[StephanStS]

You also get USB cable extensions with power switches. I saw that some of these power lines have a too high resistance so that the voltage drop is too high and the PI hardware does not run stable. I have tested several different ones of them with my different PIs. This could be kept in mind if choosing this option.
I assume that power supplies with built in switch should be aware of this, but cheap (asian) power cable extensions...

[tifDev]

Personally I'm using this case. Got it on Amazon including the power supply
https://www.amazon.de/dp/B07TYW63M8/ref=cm_sw_r_cp_apa_i_gM84EbNANWETD

@Joulinar That's nice, i'm going to buy one. Thanks for referring that.

[StephanStS]

For my several PIs etc. at one place I use this power tower (also works with RPI4, headless operation, although the RPI4 power supply should officially be stronger).
As far as I read the technical data sheet, it has a quite good surge protection built in (so called Type 3 SPD, Surge protection device). See there or there.
Hope it helps in case of lightning... :-)

[MichaIng]

Failed to connect to bus: No such file or directory

I'm wondering that you still see this error. Could you please paste the output of:

systemctl status dbus

[tifDev]

@MichaIng Same output

$ systemctl status dbus
Failed to connect to bus: No such file or directory

I believe there is no systemctl installed.

[MichaIng]

I believe there is no systemctl installed.

Then you would see "bash: systemctl: command not found" and your system would not boot 😉.

Please try the following:

mkdir /run/dbus
apt install --reinstall dbus # Carefully watch output for any error
systemctl restart dbus
systemctl status dbus

[tifDev]

I've installed another DietPi from the same image of my previous installation (just to test with no worries :p )
Apparently everything ran well.
This was the output:

What are the steps from here?

[MichaIng]

Okay and the "bus not found" error still persists? To test without actual suspend:

systemctl --dry-run suspend

[tifDev]

I ran that and it showed nothing, it was like if just hited enter in an empty terminal line...

[MichaIng]

That is expected, it's just a dry run to check if the dbus error still appears. Since it does not, systemctl suspend should now work as far as the SBC supports it 😉.

[tifDev]

Without dry-run:

Failed to set wall message: Unit systemd-login.service is masked.
Failed to suspend system via logind: Unit systemd-logind.service is masked.

So it looks like it's not possible with RPI :)

Thanks for your time!

[Joulinar]

did you run systemctl unmask systemd-logind before?

[MichaIng]

Jep + systemctl start systemd-logind as mentioned above: https://github.com/MichaIng/DietPi/issues/3596#issuecomment-642709775

[tifDev]

@Joulinar Nop.

Now i ran:

systemctl unmask systemd-logind
systemctl start systemd-logind
systemctl restart dbus
systemctl suspend

Got this message:
Failed to suspend system via logind: Sleep verb "suspend" not supported

[Joulinar]

still I don't think this is working on Raspberry Pi devices. You just can run poweroff

[tifDev]

To shutdown? For that i run sudo shutdown -h now
Yes for what I see it's not possible. I did some searches but I always see that RPI it's not made for that.
Thanks btw.

[MichaIng]

shutdown now
shutdown -h now
poweroff
systemctl poweroff

• The above do all exactly the same on a systemd init system 😉.

Failed to suspend system via logind: Sleep verb "suspend" not supported

That makes it clear: "not supported"

[tifDev]

Closing this... Thanks guys