this post was submitted on 10 Sep 2024
26 points (76.0% liked)

Privacy

32173 readers
156 users here now

A place to discuss privacy and freedom in the digital world.

Privacy has become a very important issue in modern society, with companies and governments constantly abusing their power, more and more people are waking up to the importance of digital privacy.

In this community everyone is welcome to post links and discuss topics related to privacy.

Some Rules

Related communities

much thanks to @gary_host_laptop for the logo design :)

founded 5 years ago
MODERATORS
 

Greetings! So recently, i spent a few hours coding software. After i was done and i shut off my pc, i noticed both of the ethernet lights were on and blinking. Does this mean that Microsoft is sending data to their servers before the PC fully shuts off? I am scared that this might be the thing it does. How can i get rid of this issue? I have no idea if it's related to Windows or the PC itself.

all 46 comments
sorted by: hot top controversial new old
[–] breadsmasher 50 points 3 months ago (1 children)

Does your PC support Wake-On-Lan? Effectively, leaving the port powered to allow switching on over the network

https://en.wikipedia.org/wiki/Wake-on-LAN

[–] [email protected] 16 points 3 months ago* (last edited 3 months ago) (3 children)

It does, but wake on lan is disabled in the BIOS.

[–] [email protected] 14 points 3 months ago

Power to the port may be hardwired for that feature to exist even though you have it disabled. Usually older models, but some do stay on just from being powered.

If it's a privacy concern check at your router and see if it holds an address.

[–] [email protected] 3 points 3 months ago

Try toggling ErP setting or similarly named EU energy setting in your UEFI. This should resolve the lights being on.

[–] scutiger 0 points 3 months ago (1 children)

Windows by default doesn't fully power off when you tell it to shut down. It goes into hibernation and keeps the network open for updates and will sometimes power back on to complete these updates.

If you want to fully power off, hold the left shift key when you click shut down. Or turn the power off elsewhere (eg. psu or power bar.) I'm sure there's another way to do it, or to prevent the behavior entirely.

[–] [email protected] 2 points 3 months ago (1 children)

This isn't correct at all. You are confusing fast boot and sleep. When Windows goes to sleep (I think it is S4) is when it can come back up for updates. However, during sleep networking is not active. It just wakes back up on a timer. Fast boot isn't sleep at all. It just a fancy shutdown mode that doesn't unmount the boot disk before shutdown. It also caches the system state to improve the startup time.

[–] scutiger 1 points 3 months ago (1 children)

Fast boot is just Windows logging you out of your session, then hibernating.

Sleep is keeping the computer in a low-power state with RAM powered on..

Both of these have been known to result in laptops powering on unbeknownst to their owners to perform updates and remain powered on afterward.

[–] Bitswap 0 points 3 months ago

Windows is never responsible for this. It is errors in the EC code or BIOS wake timers. When you click shutdown, the system is powered off. Windows hands off execution to Bios code for shutdown after the cycling dots saying "shutdown".

[–] [email protected] 42 points 3 months ago

Your PC network card keeps the connection up in order to receive wake on LAN requests.

Any link activity whilst the PC is shutdown is packets that were broadcasted to the entire network. Other PCs, DHCP requests, etc send traffic to all devices on the network. So seeing some traffic whilst it's off is nothing to worry about.

[–] [email protected] 24 points 3 months ago (2 children)

the link light is powered by the switch. it doesnt [necessarily] mean data transfer

[–] [email protected] 13 points 3 months ago* (last edited 3 months ago) (2 children)

the link light is powered by the switch

No it's not. If you don't believe me, unplug your PC's power cord and watch the light go out.

If the power cord is plugged in but the computer is shutdown, and the light is still on, then that means the network adapter supports WoL or OOB management and must stay on for that reason, but the network switch connected to the adapter is not physically powering any lights.

[–] [email protected] 1 points 3 months ago (1 children)

If the power cord is plugged in but the computer is shutdown, and the light is still on, then that means the network adapter supports WoL or OOB management and must stay on for that reason

Also worth noting that Windows is especially bad about actually shutting down when you tell it to shut down because something something fastboot. I've seen similar inconsistently on Linux but I strongly suspect that to be more edgecases with specific hardware and my install.

[–] [email protected] 1 points 3 months ago

Fastboot shouldn't affect networking as the hardware itself is powered off.

[–] [email protected] -1 points 3 months ago* (last edited 3 months ago) (1 children)

For cameras on some devices, the camera cannot be used without completing a circuit that turns on a light. I think they're just stating the same is true for the ethernet port light.

[–] [email protected] 4 points 3 months ago (1 children)

Except neither of those things are true.

[–] [email protected] -1 points 3 months ago* (last edited 3 months ago) (1 children)

I don't know enough about ethernet switches to know if this is common. Though, reading their comment again, I don't really think I'm right about their statement. It's definitely a light that is frequently designed to be on when packets are still being accepted for waking the computer.

I don't have a background in CE, but I've seen people claim this is sometimes a design used in the past. I think it makes sense that a circuit that is controlled by the computer can be hard wired to turn on both a light and a ethernet port. Though, I don't know how common this design is in reality.

edit: After searching some, it looks like some port lights can be controlled by a driver. I still think it probably depends on the hardware design though, and this won't be consistent between ports.

[–] [email protected] 4 points 3 months ago (1 children)

sure it depends on the design, but no standards-compliant non-PoE Ethernet design is going to light up an LED, it barely uses 1 volt.

[–] [email protected] -1 points 3 months ago (1 children)

I think driver examples from the Linux kernel are very convincing evidence that the lights can be controlled entirely by software, but I'm interested to see any possible specific port designs where that isn't true.

[–] [email protected] 4 points 3 months ago

I was not refuting that, yes drivers can control the LED since forever. The original comment was "the link light is powered by the switch", which I'm saying is not possible. An ethernet switch (assuming it's not PoE) cannot directly power an LED on a network adapter in your PC let alone the rest of it, that's all I'm saying.

[–] [email protected] 2 points 3 months ago

this 100% factually incorrect.

[–] oxomoxo 23 points 3 months ago (2 children)

You computer has a feature for Out of Band management. Either WoL as others have mentioned or vPro(Intel), iLon(HP), iDrac(Dell), as well a few other less popular systems depending on who makes your mainboard or NIC.

This leaves the power on to the network card so that it can be used even with your computer off. It does not have access to your normal computer in the this case. Just the ability to turn on/off the system and sometimes options to update BIOS/UEFI firmware and send a console image to either a client or browser.

The lights are blinking because broadcasts packets from other devices on your LAN are sent to every device. This is normal and expected behavior.

[–] [email protected] 5 points 3 months ago

The lights are blinking because broadcasts packets from other devices on your LAN are sent to every device. This is normal and expected behavior.

Just building off of this, modern computers are chatty as heck and there's just constantly little bits of chatter spamming out on LANs. This is normal and expected behavior

[–] [email protected] 1 points 3 months ago

More rarely: some poorly configured USB controllers can actually provide enough backwash power to the motherboard that some LEDs still blink, like the Ethernet indicators.

I ran into this myself, I notice the lights being on, and they stayed on when I unplugged the computer. Took me a good 5m of debugging to figure it out.

[–] [email protected] 15 points 3 months ago (2 children)

As other said, it's surely related to the LAN traffic and not the WAN traffic only your router sends some packets but it shouldn't be Windows. Little tips if you don't want telemetry and tracking, simply use Linux.

[–] [email protected] 6 points 3 months ago* (last edited 3 months ago) (2 children)

use Linux

Had to be said, didn't it?

[–] [email protected] 9 points 3 months ago

And always use proper protection when surfing online

[–] [email protected] 1 points 3 months ago

Right sorry

[–] [email protected] 4 points 3 months ago (2 children)

I dualboot both Windows and Linux. I use windows just for pyinstaller and compiling, while i daily drive Arch Linux with dwm.

[–] [email protected] 1 points 3 months ago
[–] [email protected] 1 points 3 months ago (1 children)

Why windows for pyinstaller and compiling?

[–] [email protected] 1 points 3 months ago* (last edited 3 months ago) (1 children)

Well as you may know, when you try running pyinstaller on linux, it packs the .py file into a linux exectuable, not a windows executable.

[–] [email protected] 1 points 3 months ago (1 children)

Very interesting! Thanks for the heads up. I didnt know that. 7 years ago, they already used wine for that. https://stackoverflow.com/questions/44014390/how-to-generate-a-windows-executable-using-pyinstaller-on-linux#45065125

If all else fails you could also use a vm. Thats probably less dangerous than dual booting because of windows not playing nice with grub.

[–] [email protected] 1 points 3 months ago* (last edited 3 months ago)

I dualboot both Windows and Linux using the BIOS's boot menu. Linux installed on a seprate drive, windows on another.

[–] [email protected] 6 points 3 months ago* (last edited 3 months ago)

Maybe but probably not. Its just frames coming in from the rest of the network. The device on the other end doesn't know the computer is off.

Alternatively if the card still has power it might be just in the state Windows left it in. I could imagine it would be good to not have to reinitialize the card all the time.

Why are you concerned about telemetry on shutdown? That wouldn't make any sense as it sends your data and checks the system status in the background while you use your computer. Also it is not great practice to totally shutdown at night as that's the time when update happen. It also could theoretically wear out hardware but chances are that's not a problem on newer machines

[–] [email protected] 5 points 3 months ago
[–] [email protected] 2 points 3 months ago

I believe you can stop it by turning off a feature called "fast startup" or something like that.

[–] [email protected] 2 points 3 months ago

i noticed both of the ethernet lights were on and blinking

So usually one of the lights on the port indicates the link state (up/down and if its at full speed or a reduced speed) and the other light indicates data flow. Both lights blinking suggests either a really shoddy link state or an unusual implementation of status lights on the port. Do both lights blink while its booted and actively transferring a large file? Can you find documentation of how your device implements the indicator LEDs? (I can't tell if that's a dongle or a port on your computer)

[–] JohnnyWishbone 2 points 3 months ago

I'm sure it's legacy thing from back in the day, flashing means it's sending or receiving, solid means it's idle.

[–] [email protected] -5 points 3 months ago

disconnect ur pc from power physically if the behavior continues which i would guess it will its probably something connected to ur wifi doing something in a dumb way if it stops thats wierd as fuck but forcing the pc to shut down by holding the power button should do the trick since that usually tells the motherboard to tell the power supply to shut off and i dont think windows gets a say on that.