How to check if the kernel version running is the one supported by Ubuntu?

Question

When I boot my machine I get a list of installed available kernels to choose from, how do I know which kernel is the one that is supported by my particular Ubuntu distro version? See the following two pictures:

Also, from the command line how do I do a similar check meaning how do I check if the running kernel version is the Ubuntu supported one for my particular Ubuntu distro version? Is there a kernel signature/id or something that can be checked?

In the first picture, what does "Ubuntu, HD password reset 3.19...." mean?

Solution

You can check the current kernel version in the repositories by

apt-cache policy linux-image-generic

You can see the kernel version used in the current system by

uname -a

For LTS Ubuntu versions the meta package may be different like

linux-image-generic-lts-vivid for 3.19 kernel in 14.04.3.

For LTS versions you can see all kernel versions by

apt-cache policy linux-image-generic*

For 14.04 you will see this kind of output

apt-cache policy linux-image-generic*
linux-image-generic-lts-utopic:
  Installed: (none)
  Candidate: 3.16.0.49.40
  Version table:
     3.16.0.49.40 0
        500 http://mirror.yandex.ru/ubuntu/ trusty-updates/main amd64 Packages
        500 http://mirror.yandex.ru/ubuntu/ trusty-security/main amd64 Packages
linux-image-generic-lts-vivid:
  Installed: 3.19.0.28.15
  Candidate: 3.19.0.28.15
  Version table:
 *** 3.19.0.28.15 0
        500 http://mirror.yandex.ru/ubuntu/ trusty-updates/main amd64 Packages
        500 http://mirror.yandex.ru/ubuntu/ trusty-security/main amd64 Packages
        100 /var/lib/dpkg/status
linux-image-generic-lts-raring:
  Installed: (none)
  Candidate: 3.13.0.63.71
  Version table:
     3.13.0.63.71 0
        500 http://mirror.yandex.ru/ubuntu/ trusty-updates/main amd64 Packages
        500 http://mirror.yandex.ru/ubuntu/ trusty-security/main amd64 Packages
     3.13.0.24.28 0
        500 http://mirror.yandex.ru/ubuntu/ trusty/main amd64 Packages
linux-image-generic-lts-quantal:
  Installed: (none)
  Candidate: 3.13.0.63.71
  Version table:
     3.13.0.63.71 0
        500 http://mirror.yandex.ru/ubuntu/ trusty-updates/main amd64 Packages
        500 http://mirror.yandex.ru/ubuntu/ trusty-security/main amd64 Packages
     3.13.0.24.28 0
        500 http://mirror.yandex.ru/ubuntu/ trusty/main amd64 Packages
linux-image-generic-lts-saucy:
  Installed: (none)
  Candidate: 3.13.0.63.71
  Version table:
     3.13.0.63.71 0
        500 http://mirror.yandex.ru/ubuntu/ trusty-updates/main amd64 Packages
        500 http://mirror.yandex.ru/ubuntu/ trusty-security/main amd64 Packages
     3.13.0.24.28 0
        500 http://mirror.yandex.ru/ubuntu/ trusty/main amd64 Packages
linux-image-generic:
  Installed: (none)
  Candidate: 3.13.0.63.71
  Version table:
     3.13.0.63.71 0
        500 http://mirror.yandex.ru/ubuntu/ trusty-updates/main amd64 Packages
        500 http://mirror.yandex.ru/ubuntu/ trusty-security/main amd64 Packages
     3.13.0.24.28 0
        500 http://mirror.yandex.ru/ubuntu/ trusty/main amd64 Packages
linux-image-generic-lts-trusty:
  Installed: (none)
  Candidate: 3.13.0.63.71
  Version table:
     3.13.0.63.71 0
        500 http://mirror.yandex.ru/ubuntu/ trusty-updates/main amd64 Packages
        500 http://mirror.yandex.ru/ubuntu/ trusty-security/main amd64 Packages
     3.13.0.24.28 0
        500 http://mirror.yandex.ru/ubuntu/ trusty/main amd64 Packages

In your case kernels 4.0.1-040001, 4.0.0-040002 and 3.19.0-031900 are unsupported.

The supported version format is like 3.19.0.28-generic.

3.19 is the mainline kernel version. 28 is the build number. generic is a flavor.

You can also install synaptic and see there the details of installed kernel packages and also remove unneeded kernel images and headers.

Comments

[Markus]

Thanks for the answer! Regarding "For LTS Ubuntu versions the meta package may be different", how do I know if my machine is running an LTS Ubuntu version? Also, from the Grub boot menu shown in the pictures in the original question above, how do I know which kernel is the "supported" kernel?

[Markus]

Thanks! What do you mean by " In grub menu you can check only by the version format."?

[Pilot6]

I added to the end of my answer. In grub you see only version. But you can use Synaptic to see more details.

[Markus]

Thanks again! Sorry for asking the followups, but what kind of additional details can I find in Synaptic, and how do I find it? I launched "Synaptic package manager" and typed "kernel" in the "Quick filter", but not sure if this is what you mean?

[Pilot6]

Type linux-image in the search box. You will see the packages and where they have been installed from.

[Markus]

Thanks! When you say I can see "where they have been installed from", do you mean to click on the changelog and read the info there? I don't seem to find any other info in Synaptic.