1w ago

Options for remote Wake-on-lan. Or I guess wake on WAN.

So I want to setup a remote backup location at my parents house although they are very mindful about there electricity usage and environmental impact (and so am I) so I don't want to have to have a pc always on when it doesn't need to be.

Is it possible to setup remote Wake-on-lan so I can schedule my homelab at my place to wake up the server at my parents house and start a backup like once a week, I want to do this in a secure fashion as well so ideally no port forwarding, I currently use cloudflare tunnels for my home network.

Are there any other options or do you have a similar setup at your place?

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Similar to others, I do this but the reverse direction. I have a Pi with HDD at a friend's house. On a timer, it wakes up at 3am, boots to a VPN and initiates an rsync (pull) with it's twin Pi at my place. When the sync is done, it powers down or the timer cuts power at 9am.
Other than clock drift due to power outages, I've had no issues.
I have a directory that i can put scripts into and the remote Pi will execute anything in this directory after the sync and before the shutdown. Logs from the rsync or scripts are pushed back to a different directory on the local Pi.
Home Assistant can send wake on lan commands.
If you have a remotely accessible Home Assistant Server on your LAN it can send the commands for you on the LAN while you access it remotely.
- I don't have home assistant setup in my parents place, that is a nice feature though I might use that for other things.
I've been mentally experimenting with an ESP32 hooked up to my desktop's PWR header with a switch. I've done worse than that before, so I know it'll work. I just haven't gotten my ass around to it. I can send commands to it through my domain via Apache acting as a reverse proxy.
- Hey I did exactly this a few years ago! Uses an optocoulper for isolation. I flashed ESPHome on it and connected it to my Home Assistant instance.
  Works like a charm!
  I also hard wired the ESP power pins to the PC via a spare USB header. Then I enabled a BIOS setting to keep USB ports powered when shut down, so it’s a super seamless install.
  Only problem I’m having with it lately is since I run a dual boot system, my default GRUB option is Linux, but sometimes (unfortunately) I need to get into Windows. It’s a bit of a pain to have to update grub to change the default then restart again. I’d rather build in some sort of selection functionality the first time it boots.
  I’ve been playing around with using another ESP32 as a filesystem USB device, then having grub read the content of a file on said ESP32, either “windows” or “linux”, then booting accordingly. That’s a work in progress tho
- That actually seams pretty awsome, just using a really low powered device to send WOL commands.
- There are ready made modules for it that slot into an unused PCIe slot into your case. They are available on aliexpress, search for „tuya WiFi pc power switch)
For a reliable and useful remote control solution, you're looking for an IPKVM with ATX power control. To setup the power control, you effectively set up a parallel circuit where your power switch connects to the motherboard, letting the KVM effectively press the power button 'normally'. As a bonus, you can connect to the video and data of the KVM for even more remote control options, like be able to troubleshoot boot issues or load a virtual CD/DVD to upgrade the OS.
For tinkerers, I recommend the PiKVM, either DIY or Preassembled. It's important to know that a RaspberryPi is energy efficient compared to an x86. This guy crunched the numbers
If you're looking for a product instead of a project, I'd recommend JetKVM.
- That is a lot of money for me, especially if all I need it to do is simulate the on button. Surely there is some really cheap arm based device that has an ethernet port and can therefore send WOL signals.
  
  I'm not sure what to tell ya. A cheap ARM device is the CanaKit 2GB Raspberry Pi 4 starter kit costs $110, but the JetKVM I recommended above including the ATX adapter is also $110
  https://www.amazon.com/CanaKit-Raspberry-4GB-Starter-Kit/dp/B07V2B4W63/
  https://www.wisdpi.com/products/jetkvm
  https://www.wisdpi.com/products/atx-extension-board
  The only setup I can imagine that's technically cheaper is an esp32 flashed with firmware, as discussed by another user (you already replied to it): https://lemmy.world/comment/20842145
  But the esp32 (regardless of if you use a wire to simulate a button press, or have the device generate the WoL packet) is gonna be a pain to setup and flash by comparison to the other options.
  If you already have a pi, it just needs to be flashed with Raspbian and install the app etherwake 'sudo apt-get install etherwake' and run it with 'sudo etherwake [target MAC]'.
I have a Raspberry Pi with a Wireguard VPN on it. So on my android phone, I connect to the Wireguard VPN, and then I use this app to trigger the WakeOnLan:
https://play.google.com/store/apps/details?id=com.bitklog.wolon
You could use a very low power computer that's always on like a Raspberry PI Zero W to send the WoL packet to the backup computer. It only uses about 1 watt. Some routers have the ability to send a WoL packet as well.
- thats a good idea, although wifi is not reliable enough for me. Although I found this guide which shows how to add an ethernet port to a PI zero w so hopefully I can use that. Or maybe I should just use a ESP32.
- You can even use an ESP32 or similar since it just has to perform 1 tiny function.
  Getting an WT32-ETH01 knockoff dev board for 15€ or PoE for 25€ and uses <300mW with the wireless modem off. You could even just use a WiFi module for 8€ if you don't want something wired.
  https://registry.platformio.org/libraries/a7md0/WakeOnLan
  There is already an wakeonlan library to generate a packet very easily.
  You can even do it in pseudocode with ESPHome if you have HomeAssistant
  https://community.home-assistant.io/t/solved-wake-on-lan-packet-from-esp32-to-ha-server-how-to-automate/617595
  Then VPN in, send a signal to the esp using one of various methods to tell it to send the packet.
  
  Then VPN in, send a signal to the esp using one of various methods to tell it to send the packet.
  this sounds like it requires another computer already turned on
- And how do you communicate with the Pi0?
  
  Use SSH. Ether open a port in the firewall or connect it to a VPN. If the backups are done on a schedule, you could also setup a cron job on the Pi to send the WoL packet a few minutes ahead of time.
If timers on the bios aren't an option, look for the settings to power on after power outage. If you turn it on, you can use a standard timer plug to turn the power on and off.
Can you set the BIOS to wake up at a certain time? Many have that option.
- I didn't realise the bios could do that I will look into that.
  
  https://man.archlinux.org/man/rtcwake.8.en
Just ask Ian to start your computer when he goes on it
- Lan is not the name of my parent 💀
I use Upsnap on a low-power SBC behind a reverse proxy: https://github.com/seriousm4x/UpSnap
Before that I used the WoL feature on my Asus router.
I do backups with a Raspberry Pi with a 1TB SD card and leave it on all the time. The power draw is very small and I think reasonable for the value of offsite backups.
My personal experience with WOL (or anything related to power state of computers) is that it’s not reliable enough for something offsite. If you can set something up that’s stable, awesome, but if your backup server is down and you need to travel to it, that suuuucks.
- I already have 2x2tb hard drives, a singular sd card is not enough for me I need some level of redundancy even for my backups.
- Friendly warning that SD cards are not a backup. Those things die, frequently and without warning. They also bitrot fast. If you value the data being backed up, choose a more stable medium.
Wake on LAN is a LAN feature, not WAN, so you'd need to issue that over the local LAN there at the house. You're going to have a hard time trying to get that working over the WAN (if that's even possible).
The other comments mentioning a scheduled boot would be a much easier/simple solution if it works for you.
But I'll throw this in, the super basic least tech solution to this is to open a port forward to the house's network router. Yes, I know you don't want to do that, but it's probably the only network device at that house that's actually on 24/7 right? And by all means lock it down however you like. My simple method is to open the router login to a non-standard port number, with a IP whitelist, add my own home IP address to that IP whitelist, and bam you now have access to that remote home's router for just your IP address. Log in remotely, issue a wake on LAN via the router's own web ui, done.
It's perfectly reasonable to make this a bit more secure if you wanted but it gets slightly more complicated - open a non-standard port for SSH access to the remote router's SSH port that only allows SSH login with key. Generate a SSH key and share that key with yourself, then you can log in remotely to that remote house via non-standard SSH port using the SSH key (no user/passwords). From there you'd have to see if you can issue Wake on LAN on the SSH command line, or set up a SSH tunnel from that remote LAN to yours so you can proxy into the router login page and do your Wake on LAN from there. ... yes I realize this got complicated :/ But you've got a few things to explore given your patience for tinkering with this stuff :)
Of course much of this relies on that house's router having any of these features to enable and configure. The main takeaway here is that Wake on LAN requires something on 24/7 at that remote LAN for you to enable remote access into and issue a Wake on LAN command within that LAN. How to actually accomplish that is the tricky bit.
- You're going to have a hard time trying to get that working over the WAN (if that's even possible).
  Wake on LAN is still encapsulated in an IP packet, so you can send it over the internet, and most WOL clients let you specify an IP. However your router will need to DNAT it to a broadcast address. Some routers have a check box for this (e.g. An ISP provided Technicolor router I have), some let you port forward to broadcast (e.g. Many routers, sometimes with workarounds), and some let you manually configure NAT (e.g. MikroTik routers).
  So it is possible, but forwarding public internet traffic to a broadcast address seems like a bad idea, and I wouldn't recommend it. Why I know this: I used to do this in middle school, and it does work quite well.
  
  Well believe it or not, I used to do it too, by forwarding it directly to the lan host on port 9. No broadcasting required, just a regular UDP packet. I had a really shitty ISP router.
  Would have to try again but I’m almost certain it would work, as long as the computer’s MAC address is still in the router’s ARP table.
you can configure bios for self power on at certain time and then turn the server off after finishing backup
- Second that. I don't have another node that I can use for WoL at my backup location so I opted for the node to turn on every morning, run the backup and turn off using cron at a given time. Works perfectly!
it ain't pretty, and may not quite suit what you're looking for. other comments recommending a pi or similar are likely better taste. but here's what I've done:
I have a cheap Android tablet that stays home and is connected to our home network. if needed, I connect to the tablet with TeamViewer and use a WoL app to send the packet to my computer on that same network.
Booting on a schedule as others have suggested would be the simplest by far.
To answer as asked though, it's not something I've needed to do but it sounds like a VPN + IGMP proxy (I'm assuming you have a separate subnet for your VPN) might fit the bill.
Alternatively some kind of low power device (a Pi or something) that lives in the same subnet could make the WOL call locally, and you just need to find a way to trigger it. Could do it via a http call for example.

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