Difference between revisions of "Manjaro Kernels"

<translate>

<translate>

As the name would imply, as with the kernel of a seed, the Linux kernel is the core of a Linux operating system. Every other element of a Linux-based operating system is built around the kernel, which acts as an interface between your computer's hardware and the applications that run on it. As hardware and software applications become more complex and sophisticated, so do the kernels to fully utilise them. As such, Linux kernels are continually under development, with new revisions and versions being regularly released. Further information on the very latest developments in kernel technology can be found at [http://www.kernel.org/ The Linux Kernel Archives]

As the name would imply, as with the kernel of a seed, the Linux kernel is the core of a Linux operating system. Every other element of a Linux-based operating system is built around the kernel, which acts as an interface between your computer's hardware and the applications that run on it. As hardware and software applications become more complex and sophisticated, so do the kernels to fully utilise them. As such, Linux kernels are continually under development, with new revisions and versions being regularly released. Further information on the very latest developments in kernel technology can be found at [http://www.kernel.org/ The Linux Kernel Archives]

The first Linux kernel was originally developed by [http://en.wikipedia.org/wiki/Linus_Torvalds Linus Torvalds], the creator of Linux. It is now an open-source project containing millions of lines of code generated by thousands of programmers.  However, Linus Torvalds still has the final authority on their development and release.

The first Linux kernel was originally developed by [http://en.wikipedia.org/wiki/Linus_Torvalds Linus Torvalds], the creator of Linux. It is now an open-source project containing millions of lines of code generated by thousands of programmers.  However, Linus Torvalds still has the final authority on their development and release.

[[File:Msm-kernels.jpg|thumb|left|375px]]

[[File:Msm-kernels.jpg|thumb|left|375px]]

[[Manjaro Settings Manager]] offers an easy way to add and remove kernel (including the necessary kernel modules).

[[Manjaro Settings Manager]] offers an easy way to add and remove kernel (including the necessary kernel modules).

New kernels can be installed by pressing the "Install" button.  All necessary kernel modules will be installed automatically with a new kernel as well.   

New kernels can be installed by pressing the "Install" button.  All necessary kernel modules will be installed automatically with a new kernel as well.   

Please consider the "Recommended" tag when choosing a kernel.  LTS means Long Term Support, which is safest for most users.

Please consider the "Recommended" tag when choosing a kernel.  LTS means Long Term Support, which is safest for most users.

The newest installed Kernel will be booted by default, but to run other kernels that are installed, see [[Manjaro_Kernels#Selecting_Kernels|Selecting Kernels]] section below.

The newest installed Kernel will be booted by default, but to run other kernels that are installed, see [[Manjaro_Kernels#Selecting_Kernels|Selecting Kernels]] section below.

<br clear="all" />

<br clear="all" />

Instead of using the [[Manjaro Settings Manager]] GUI to identify, choose, add, and remove kernels everything can be achieved from a terminal as well.

Instead of using the [[Manjaro Settings Manager]] GUI to identify, choose, add, and remove kernels everything can be achieved from a terminal as well.

This terminal command will give your system's kernel information:

This terminal command will give your system's kernel information:

The above command not only shows which kernel is being used, it also lists any other kernels that are also installed, as shown in the following example Terminal output:

The above command not only shows which kernel is being used, it also lists any other kernels that are also installed, as shown in the following example Terminal output:

  Currently running: 5.0.17-1-MANJARO (linux50)

  Currently running: 5.0.17-1-MANJARO (linux50)

  The following kernels are installed in your system:

  The following kernels are installed in your system:

     * linux50

     * linux50

As seen in the above example, Manjaro is running kernel 5.0.17-1-MANJARO. The information given here is not arbitrary; each part of the kernel name identifies something about that kernel:

As seen in the above example, Manjaro is running kernel 5.0.17-1-MANJARO. The information given here is not arbitrary; each part of the kernel name identifies something about that kernel:

* The 5 indicates the version

* The 5 indicates the version

* The 0 indicates the major revision

* The 0 indicates the major revision

{{tip| '''mhwd-kernel will automatically update a newly installed kernel with any modules currently used in your existing kernel'''. For example, if you were to update from kernel 4.14 to 4.19, mhwd-kernel would automatically update 4.19 with any and all modules present in 4.14. How about that!}}

{{tip| '''mhwd-kernel will automatically update a newly installed kernel with any modules currently used in your existing kernel'''. For example, if you were to update from kernel 4.14 to 4.19, mhwd-kernel would automatically update 4.19 with any and all modules present in 4.14. How about that!}}

Manjaro not only supports the use of ''multiple'' kernels (selectable from the boot screen), but allows easy access to the '''very latest ''bleeding edge''''' kernels as well. This is undertaken through use of Manjaro's own ''MHWD-kernel'' (Manjaro Hard-Ware Detection) command. The syntax of the command is as follows:

Manjaro not only supports the use of ''multiple'' kernels (selectable from the boot screen), but allows easy access to the '''very latest ''bleeding edge''''' kernels as well. This is undertaken through use of Manjaro's own ''MHWD-kernel'' (Manjaro Hard-Ware Detection) command. The syntax of the command is as follows:

When listing a new kernel to be installed in the command, it is not necessary to write the entire version number. For example, any version of Kernel 4.19 can be listed simply as 'linux419', and any version of Kernel 4.14 can be listed as 'linux414', and so on.  

When listing a new kernel to be installed in the command, it is not necessary to write the entire version number. For example, any version of Kernel 4.19 can be listed simply as 'linux419', and any version of Kernel 4.14 can be listed as 'linux414', and so on.  

The optional '''rmc''' ('''<u>r</u>'''e'''<u>m</u>'''ove '''<u>c</u>'''urrent) component is of vital importance. Using this will result in your existing kernel being deleted upon the installation of the new kernel. Otherwise, if it is not used, then the existing kernel will be kept, and will be selectable alongside the new kernel at the boot screen. '''It is recommended - especially if updating to the latest bleeding edge kernel - to keep your old one, even if only for a short time afterwards'''. This the safer option, and the old kernel can be easily removed when satisfied with the stability and functionality of the new one.  

The optional '''rmc''' ('''<u>r</u>'''e'''<u>m</u>'''ove '''<u>c</u>'''urrent) component is of vital importance. Using this will result in your existing kernel being deleted upon the installation of the new kernel. Otherwise, if it is not used, then the existing kernel will be kept, and will be selectable alongside the new kernel at the boot screen. '''It is recommended - especially if updating to the latest bleeding edge kernel - to keep your old one, even if only for a short time afterwards'''. This the safer option, and the old kernel can be easily removed when satisfied with the stability and functionality of the new one.  

As an example, once the terminal is opened, the following command will install a new kernel (4.19) '''without deleting the existing kernel currently being used''':

As an example, once the terminal is opened, the following command will install a new kernel (4.19) '''without deleting the existing kernel currently being used''':

Otherwise, the following command will install a new kernel (5.10) to replace the existing kernel, '''which will be deleted''':

Otherwise, the following command will install a new kernel (5.10) to replace the existing kernel, '''which will be deleted''':

Either way, Manjaro will automatically configure the new kernel for you, ready for immediate use. Once completed, close the terminal and re-boot the system for the change to take effect.

Either way, Manjaro will automatically configure the new kernel for you, ready for immediate use. Once completed, close the terminal and re-boot the system for the change to take effect.

{{warning|DO NOT attempt to delete an existing kernel while it is actually being used by Manjaro at the time. You can first identify what kernel is running on your system by using the command '''mhwd-kernel -li''' in the terminal (see above).}}

{{warning|DO NOT attempt to delete an existing kernel while it is actually being used by Manjaro at the time. You can first identify what kernel is running on your system by using the command '''mhwd-kernel -li''' in the terminal (see above).}}

Where multiple kernels are present on your system, ''pacman'' can be used to remove them in the terminal. It may be necessary to delete a total of three elements of the kernel in total to completely remove it:

Where multiple kernels are present on your system, ''pacman'' can be used to remove them in the terminal. It may be necessary to delete a total of three elements of the kernel in total to completely remove it:

# The kernel itself

# The kernel itself

# The kernel's headers

# The kernel's headers

# The kernel's extra modules

# The kernel's extra modules

Whether or not the headers and extra modules must be deleted depends on whether or not they have been installed.

Whether or not the headers and extra modules must be deleted depends on whether or not they have been installed.

1. '''To remove a kernel''' use the following syntax:

1. '''To remove a kernel''' use the following syntax:

  sudo mhwd-kernel -r linux[version]

  sudo mhwd-kernel -r linux[version]

Here is an example for removing kernel 5.0.17-1

Here is an example for removing kernel 5.0.17-1

2. '''To delete a kernel's headers''', the syntax is:

2. '''To delete a kernel's headers''', the syntax is:

  sudo pacman -R linux[version]-headers

  sudo pacman -R linux[version]-headers

For example, to delete the headers of kernel version 5.0.x from the system, the following command would be entered:

For example, to delete the headers of kernel version 5.0.x from the system, the following command would be entered:

  sudo pacman -R linux50-headers

  sudo pacman -R linux50-headers

3. '''To delete a kernel's extra modules''', the syntax is:

3. '''To delete a kernel's extra modules''', the syntax is:

  sudo pacman -R linux[version]-extramodules

  sudo pacman -R linux[version]-extramodules

For example, to delete the extra modules of kernel version 5.0.x from the system, the following command would be entered:

For example, to delete the extra modules of kernel version 5.0.x from the system, the following command would be entered:

  sudo pacman -R linux50-extramodules

  sudo pacman -R linux50-extramodules

4. '''To delete all elements of a kernel at the same time'''  - where they are all present on your system - the syntax is:

4. '''To delete all elements of a kernel at the same time'''  - where they are all present on your system - the syntax is:

  sudo pacman -R linux[version] linux[version]-headers linux[version]-extramodules

  sudo pacman -R linux[version] linux[version]-headers linux[version]-extramodules

For example, to completely remove all elements of kernel version 5.0.x, the following command would be entered:

For example, to completely remove all elements of kernel version 5.0.x, the following command would be entered:

  sudo pacman -R linux50 linux50-headers linux50-extramodules

  sudo pacman -R linux50 linux50-headers linux50-extramodules

Please note however, that attempting to delete multiple elements at once if they are not present on your system will result in an error message before the operation itself is aborted. It is also worthwhile noting if Manjaro is being run in a virtual machine (e.g. Oracle Virtualbox), you may not be able to delete certain kernels if they contain elements important to the virtualisation process itself.

Please note however, that attempting to delete multiple elements at once if they are not present on your system will result in an error message before the operation itself is aborted. It is also worthwhile noting if Manjaro is being run in a virtual machine (e.g. Oracle Virtualbox), you may not be able to delete certain kernels if they contain elements important to the virtualisation process itself.

As with most Linux commands that can be entered into the Terminal, typing the command followed by either '''-h''' or '''--help''' will print out the usage & available options to the Terminal for your reference. Here is the output of the '''mhwd-kernel -h''' command:

As with most Linux commands that can be entered into the Terminal, typing the command followed by either '''-h''' or '''--help''' will print out the usage & available options to the Terminal for your reference. Here is the output of the '''mhwd-kernel -h''' command:

  Usage: mhwd-kernel [option]

  Usage: mhwd-kernel [option]

     -h  --help              Show this help message

     -h  --help              Show this help message

[[file:kernel_select.png|thumb|left|375px]]

[[file:kernel_select.png|thumb|left|375px]]

All available kernels installed on your system will be presented upon booting up. GNU GRUB is visible with a couple of options. Choose "Advanced Options for Manjaro Linux" by using the arrow keys on your keyboard and then press <Enter>.  

All available kernels installed on your system will be presented upon booting up. GNU GRUB is visible with a couple of options. Choose "Advanced Options for Manjaro Linux" by using the arrow keys on your keyboard and then press <Enter>.  

On the next screen (as illustrated) are backup copies of each kernel version installed (which will also be automatically removed if or when a kernel version is deleted). To select a kernel, simply use the arrow keys to highlight the desired version, and then press <Enter>.

On the next screen (as illustrated) are backup copies of each kernel version installed (which will also be automatically removed if or when a kernel version is deleted). To select a kernel, simply use the arrow keys to highlight the desired version, and then press <Enter>.

<br clear="all"/>

<br clear="all"/>

[https://wiki.manjaro.org/index.php?title=Mhwd-kern.sh MHWD-kern - a lightweight kernel wizard]

[https://wiki.manjaro.org/index.php?title=Mhwd-kern.sh MHWD-kern - a lightweight kernel wizard]