Low-power home server : recycling an old netbook
When it comes to begin self-hosting or doing homelabbing on a budget, single board computers (SBC) like the RaspberryPi are often mentioned as a good starting point : they are affordable, small, they doesn’t require much power to run and a vast community is supporting them.
Even though I’ve read many reviews and watched tons of videos about SBCs usages, I don’t own one (yet).
You might be thinking “I should get one of those too”, and while you’re not wrong, you may also consider another option : recycling an old machine, and more specifically a low power netbook PC that could do the job and maybe even more.
In this post, I’m going to use a Lenovo Yoga 300 as an example. This netbook comes from a friend who had it sleeping in a shelf for quite a while now.
Nothing too exciting about this specific computer, reviews seem quite mixed about it, and I would have not bought it for myself for sure : the keyboard is really bad, the 1366×768 display is at best barely acceptable, and the CPU is struggling running the Windows 8 OS or any modern app / web browser / rich Internet content.
But on the other hand, you could see it as a very interesting little machine in a home server perspective :
- Low power : my model comes with 7,5W TDP N2840 Celeron CPU
- Silent : cooling is passive on this model
- Network : built-in gigabit NIC
- RAM : 2Gb, soldered, should be enough for the expected usage scenario, but no further upgrade
- Integrated 32Gb eMMC storage
- 1 USB3 port + 2 USB2 ports
- 1 HDMI output
That’s a lot to play with. Here is the Yoga 300 after a fresh Ubuntu Server 20.04 install on it :
The eMMC storage is a weakness to me : it is slow, not upgradable and reliability can be questioned. It actually depends what you plan to do, as it’s enough in my opinion to host light services with little storage and I/O flow requirements. To sum it up, it’s not worse than using a SD card in a SBC. Also, planning regular backups sounds like a good idea.
I should mention that this specific model can receive a regular 2,5″ drive in its internal bay, but it requires an adapter which wasn’t provided in my unit. This adapter can be bought on various websites like Ebay, Aliexpress, etc…for a few euros / dollars. Have a look at this video tutorial for installation instructions.
So you’ve got room for expansion : you can use any internal 2,5″ SATA drive that fits your use case, and the 3 USB ports offer many possibilities too. Depending on the OS/usage you plan to have, mounting drives through the USB3 port could be a valid option.
In my opinion, this machine could be a very neat entry point to a home network, while hosting a few light web apps or being a backup server for instance. So I installed docker engine and did some tests with the following apps / services (check out the “services” page for infos) :
- murmur server
In this scenario, with a couple users, the machine is perfectly suitable : the CPU usage varies between 2% and 10%, at ~35° (room is at ~20°), RAM usage is around 400/500Mb, while being completely silent. It would nicely fit next to your router or under your TV for instance.
I also plugged a 2,5″ HDD on the USB3 port, installed cifs-utils and mounted it to a shared folder to perform some read and write operations from my laptop. Depending on the type and the size of files, SMB transfer speed varies between 20Mb/s to 70Mb/s, with no major impact on CPU usage. So in a light NAS usage scenario this is also a viable solution, even though your results may vastly depend on how many users are transferring files. As a media storage or a system backup solution, it could do the trick for instance.
Now about power consumption : this is probably the best part, as this machine is idleing at 4-5W with screen off, and goes up to ~15W under heavy load.
And I did not make any tweak, it is just a freshly installed Ubuntu Server. Using another more lightweight distro with tools like TLP for instance would probably get this number down to 2-3W (at idle). Those low-voltage CPUs are doing marvels.
Also, another pro for a netbook : it offers sort of a built-in UPS. The battery on my unit is in very good condition, and the machine can stay up and running more than 6 hours in case of an electric surge. That said, you should still consider getting an UPS to protect your setup from voltage pikes and other over-voltage problems to name a few.
I did not cover all the possible usages, the point here is to show how convenient it can be to recycle an old sleeping netbook, as a cheap and efficient solution, and while not being an all-round solution, I think people should consider it before buying something new.
I’ll keep this neat little machine as a backup one for now, and I’ll maybe offer it to a friend later.
SBCs like the RaspberryPi have specific features a netbook doesn’t have, like the built-in GPIO for instance. I’m not saying SBCs are a bad choice, as I think it’s a very good thing this kind of products emerged to the market in the recent years. But depending on what you want to do, learn or experiment, using old hardware is always something to consider. Your wallet will thank you.