Need a Fixed Camera in Linux? Easy Bind to /dev/video

Okay, so today I ran into a bit of a snag with my camera setup on Linux. I’ve got this webcam that I use for streaming, and I wanted it to always be recognized as the same /dev/video device. You know, for consistency’s sake. It was a pain when the device number kept changing every time I plugged it in or rebooted.

So, I rolled up my sleeves and started digging around. First thing I did was check which video devices were actually being detected by my system. I just typed

• ls -l /dev/video

into the terminal, and it showed me all the video devices that were currently connected. Then, to see what was connected to my USB ports, I used:

• lsusb

This gave me a clearer picture of which device was which. After identifying my camera, I wanted to create a rule that would always assign it to a specific /dev/video device, like /dev/video10, for example. It seemed like udev rules were the way to go.

I found some examples online, but they were a bit confusing at first. But I got the hang of it. Basically, I needed to create a new rule file in the /etc/udev/rules.d/ directory. I named it something like *, and inside, I started writing the rule. I had to use the camera’s vendor and product IDs, which I found using lsusb.

My udev rule ended up looking something like this:

• SUBSYSTEM==”video4linux”, ATTRS{idVendor}==”1234″, ATTRS{idProduct}==”5678″, SYMLINK+=”my-camera”

Of course, “1234” and “5678” were replaced with my camera’s actual IDs. And “my-camera” is just a name I picked, I could’ve named it anything that made sense to me.

After saving the rule file, I reloaded the udev rules with:

• sudo udevadm control –reload-rules

And then triggered udev to apply the new rule:

• sudo udevadm trigger

I unplugged and replugged my camera, and voila! A new symlink /dev/my-camera appeared, always pointing to the correct /dev/video device. It was a small victory, but it made my setup so much more reliable.

I also wanted to share this device with my Docker containers. Normally, I’d just use the –device flag when running a container, but I wanted something more permanent. After some research, I found that using the –privileged flag would expose all my host’s devices to the container. It’s not ideal for security, but for my personal setup, it was good enough. So, now my Docker containers could access /dev/my-camera just like any other application on my host.

It wasn’t a super smooth process, and I definitely hit some bumps along the way. But I learned a lot about udev rules and how Linux handles devices. It’s pretty cool how you can customize your system like this. I just wanted to share my little adventure in case anyone else is trying to wrangle their devices on Linux. It’s not as scary as it seems once you get your hands dirty!