Cannot access /sys/class/video4linux

[SKuma51]

I'm installing D415 on ubuntu 16.04

On following the instruction manual https://github.com/IntelRealSense/librealsense/blob/master/doc/distribution_linux.md, i ended up with an error on running realsense-viewer"realsense-viewer 31/10 12:04:45,653 ERROR [140307828632128] (backend-v4l2.cpp:518) Cannot access /sys/class/video4linux"My Kernel version is 4.15.0-36-genericI googled and tried various solution but still no success. Please help!!

[MartyG]

In a previous case last month of this error at the same line (backend-v412.cpp line 518), the user corrected the problem by doing a completely fresh install. They believed the cause may have been that they had their kernel versions mixed up.

https://github.com/IntelRealSense/librealsense/issues/2427# issue-362556361 realsense-viewer: Cannot access /sys/class/video4linux · Issue # 2427 · IntelRealSense/librealsense · GitHub

[SKuma51]

Installing fresh Ubuntu would take a lot of time since i have ROS packages and many other things installed.

[MartyG]

The official Ubuntu documentation has advice about removing old kernels. In practice though it may be too risky on your installation, as pulling out a kernel one or more of your programs depends on could create all sorts of problems.

https://help.ubuntu.com/community/RemoveOldKernels https://help.ubuntu.com/community/RemoveOldKernels

I wonder if an alternative would be to create a separate Ubuntu installation on a USB stick (a 'boot stick') just for Librealsense, so that you don't break your existing installation.

https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-ubuntu# 0 Create a bootable USB stick on Ubuntu | Ubuntu tutorials

[SKuma51]

I solved the issue.

DO everything and just install sudo apt-get install realsense-uvcvideo

[MartyG]

Great news! I'm really pleased you found a solution. Thanks for letting us know!

[SKuma51]

It was working fine till yesterday and now it doesn't even detect the camera. I'm getting the same old error "Cannot access /sys/class/video4linux"

Could you please help me resolve this issue.

[idata]

Hello shrijan00,

Could you please let us know the output of: lsusb ?Also, could you please update the firmware to the latest release? Link to the instructions http:// https://www.intel.com/content/www/us/en/support/articles/000028171/emerging-technologies/intel-realsense-technology.html here and you can download the firmware from https://downloadcenter.intel.com/download/28237/Latest-Firmware-for-Intel-RealSense-D400-Product-Family here.Looking forward to your reply!Best regards,Eliza

[SKuma51]

Hi,

So i uninstalled and did once again, so it is working for now.

But when using the roslaunch i'm still getting this error but using rqt_image_view iḿ still able to see image but i think this error is either due to kernel issue or sdk.

[SKuma51]

And when i run realsense-viewer, it works but in the terminal it keeps telling "UVC metadata payloads not available. Please refer to installation chapter for details."

My Kernel version is 4.15.0-36-generic

[idata]

Hello shrijan00,

On this https://github.com/intel-ros/realsense/issues/503 thread a solution for this error message is to install librealsense2-dkms with sudo apt-get install librealsense2-dkms=1.3.1-0ubuntu3I noticed that you have posted this issue on another thread too - https://intel-openport-v8.hosted.jivesoftware.com/thread/130792.Would you agree to continue the conversation there to avoid redundancy? Thank you,Eliza

[SKuma51]

Running that command, it doesn't even detect now. I removed it so at least it is working somehow withe warning

[ WARN] [1541544389.804503667]: Frame metadata isn't available! (frame_timestamp_domain = RS2_TIMESTAMP_DOMAIN_SYSTEM_TIME)