diff --git a/DC-kernel-boot-parameters-modify-non-sles b/DC-kernel-boot-parameters-modify-non-sles new file mode 100644 index 000000000..fa6a0f8c2 --- /dev/null +++ b/DC-kernel-boot-parameters-modify-non-sles @@ -0,0 +1,21 @@ +## Basics +MAIN="kernel-boot-parameters-modify.asm.xml" +SRC_DIR="articles" +ROOTID="kernel-boot-parameters-modify" +IMG_SRC_DIR="images" + +# Profiling +PROFOS="non-sles" +PROFARCH="x86_64;zseries;power;aarch64" +PROFCONDITION="suse-product;beta" +PROFCONDITION="community-project" + +# When content is ready for publication, comment the +# line below or set DRAFT=0 +DRAFT=0 + +## stylesheet location +STYLEROOT="/usr/share/xml/docbook/stylesheet/suse2022-ns" +FALLBACK_STYLEROOT="/usr/share/xml/docbook/stylesheet/suse-ns" + +DOCBOOK5_RNG_URI="urn:x-suse:rng:v2:geekodoc-flat" diff --git a/DC-kernel-boot-parameters-modify-sles b/DC-kernel-boot-parameters-modify-sles new file mode 100644 index 000000000..66d8fe985 --- /dev/null +++ b/DC-kernel-boot-parameters-modify-sles @@ -0,0 +1,21 @@ +## Basics +MAIN="kernel-boot-parameters-modify.asm.xml" +SRC_DIR="articles" +ROOTID="kernel-boot-parameters-modify" +IMG_SRC_DIR="images" + +# Profiling +PROFOS="sles" +PROFARCH="x86_64;zseries;power;aarch64" +PROFCONDITION="suse-product;beta" +PROFCONDITION="community-project" + +# When content is ready for publication, comment the +# line below or set DRAFT=0 +DRAFT=0 + +## stylesheet location +STYLEROOT="/usr/share/xml/docbook/stylesheet/suse2022-ns" +FALLBACK_STYLEROOT="/usr/share/xml/docbook/stylesheet/suse-ns" + +DOCBOOK5_RNG_URI="urn:x-suse:rng:v2:geekodoc-flat" diff --git a/DC-task-modify-kernel-boot-parameter b/DC-task-modify-kernel-boot-parameter deleted file mode 100644 index f7772154c..000000000 --- a/DC-task-modify-kernel-boot-parameter +++ /dev/null @@ -1,15 +0,0 @@ -# This file originates from the project https://github.com/openSUSE/doc-kit -# This file can be edited downstream. - -MAIN="task-modify-kernel-boot-parameters.xml" -ROOTID="" - -PROFOS="generic" -# PROFCONDITION="suse-product" -# PROFCONDITION="suse-product;beta" -# PROFCONDITION="community-project" - -DRAFT=1 - -STYLEROOT="/usr/share/xml/docbook/stylesheet/suse2022-ns" -FALLBACK_STYLEROOT="/usr/share/xml/docbook/stylesheet/suse2022-ns" diff --git a/articles/kernel-boot-parameters-modify.asm.xml b/articles/kernel-boot-parameters-modify.asm.xml new file mode 100644 index 000000000..48d27c1b8 --- /dev/null +++ b/articles/kernel-boot-parameters-modify.asm.xml @@ -0,0 +1,215 @@ + + + + + %entities; +]> + + + + + + + + + + For more information + + + + + + Introduction to kernel boot parameters + + + Difference between kernel boot parameters and linuxrc parameters + + + + + + Temporarily modify kernel boot parameters + + + Permanently modify kernel boot parameters + + + Troubleshooting modified kernel boot parameters + + + + + + Legal Notice + + + GNU Free Documentation License + + + + + + Modifying kernel boot parameters + + + + 12023-11-28 + + + Initial version + + + + + + + + + + + + + + + &sles;&sles;&sles;&sles;&sles;&sles; + + Modifying kernel boot parameters + Concepts, examples and modification process of kernel boot + parameters for customizing the boot process. + Process for modifying + kernel boot parameters + + + + + https://bugzilla.suse.com/enter_bug.cgi + Smart Docs + Documentation + ssarkar@suse.com + + yes + + + + + WHAT? + + + Concepts, examples and modification process of kernel boot + parameters for customizing the boot process and the subsequent + environment. + + + + + WHY? + + + Modifying kernel boot parameters is essential for achieving + specific system configurations and addressing several + scenarios, including performance optimization, better hardware + compatibility, and troubleshooting issues such as graphics + drivers. + + + + + EFFORT + + + It 15 minutes to fully understand the concepts and the process, + and 5 minutes to modify kernel boot parameters and observe its + effect after reboot. + + + + + GOAL + + + Modify kernel parameters to customize the boot process and the + subsequent environment. + + + + + REQUIREMENTS + + + Depending on whether you want to apply changes in kernel boot + parameters to the upcoming boot process, or all subsequent boot + processes, the requirements are as follows: + + + + + To change kernel boot parameters on an experimental basis + only for the upcoming boot process, there are no + requirements. + + + + + To change kernel boot parameters for all subsequent boot + processes, you should have root or + equivalent administrative privileges. + + + + + + + + + + + + + + + + + + + + + + + Troubleshooting and FAQs + + + + + + For more information + + + + + + + + + + diff --git a/concepts/kernel-boot-parameters-modify-difference-linuxrc-parameters.xml b/concepts/kernel-boot-parameters-modify-difference-linuxrc-parameters.xml new file mode 100644 index 000000000..0677f923d --- /dev/null +++ b/concepts/kernel-boot-parameters-modify-difference-linuxrc-parameters.xml @@ -0,0 +1,94 @@ + + + + + %entities; +]> + + + + + + + Difference between kernel boot parameters and linuxrc parameters + + + + + + + Kernel boot parameters and linuxrc parameters are often similar in + appearance, but conceptually they are entirely different. It is + important that you do not confuse them and understand their basic + difference. + + + +
+ What are linuxrc parameters? + + In &productname;, the linuxrc is a script that runs + during the boot process before the systems's root file system is mounted, + and serves as the initial RAM disk (initrd) entry point. The + linuxrc parameters are used within this script to + configure the system further before transitioning to the actual root file + system. + + + Similar to kernel boot parameters, you can pass linuxrc parameters either + using the command line, or using configuration files. The entries for + linuxrc parameters are similar in appearance to that of the kernel boot + parameters. + + + However, the kernel boot parameters and the linuxrc parameters are + different concepts. To learn more about the linuxrc parameters, refer to + . + +
+
+ Examples of linuxrc parameters + + To highlight the similarity in appearance, observe the following + examples: + + + + + rd.driver.blacklist=: Specifies drivers to be + blacklisted in the initrd. For example, + rd.driver.blacklist=nouveau prevents the + nouveau graphics driver from loading. + + + + + rd.break: Interrupts the boot process and drops + the system to a shell for debugging purposes within the initrd. + + + + + rd.retry=: Specifies the number of retries for + device scanning in the initrd. For example, + rd.retry=3. + + + + + rd.luks=1: Activates support for encrypted devices + in the initrd. + + + +
+
diff --git a/concepts/kernel-boot-parameters-modify-introduction.xml b/concepts/kernel-boot-parameters-modify-introduction.xml new file mode 100644 index 000000000..9815f13e0 --- /dev/null +++ b/concepts/kernel-boot-parameters-modify-introduction.xml @@ -0,0 +1,123 @@ + + + + + %entities; +]> + + + + + + + Introduction to kernel boot parameters + + + + + + + Before modifying kernel boot parameters, it is important to understand + the basic concepts - definition, examples and reasons for modifying + kernel boot parameters. + + + +
+ What are kernel boot parameters? + + Kernel boot parameters are configurations passed to the &productname; + kernel during the boot process for &grub;, instructing it on how to + configure certain features and make hem behave in the intended manner. + +
+
+ Examples of commonly modified kernel boot parameters + + There are many different kernel parameters that you can optionally modify + to customize your boot process. Based on you your use case, you can + consider few of the most commonly modified kernel boot parameters: + + + + + root=: Specifies the path to the root file system. + + + + + quiet: Suppresses most boot messages. + + + + + splash: Displays a graphical boot splash screen. + + + + + nomodeset: Disables kernel mode setting. + + + + + debug: Enables debugging output. + + + + + acpi=: Toggles the Advanced Configuration and + Power Interface (ACPI) settings. + + + + + Source documentation for kernel parameters is available at + + +
+
+ Benefits of modifying kernel boot parameters + + Modifying kernel boot parameters is essential for achieving specific + system configurations and addressing several scenarios, including: + + + + + Performance optimization + + Tweaking parameters to enhance system performance, responsiveness, + and overall efficiency based on specific system requirements. + + + + + + Hardware compatibility + + Tailoring parameters to ensure compatibility with specific hardware + components, addressing potential compatibility issues. + + + + + + Troubleshooting + + Altering parameters to troubleshoot issues such as graphics driver + problems, ensuring a more stable and functional system. + + + + +
+
diff --git a/glues/kernel-boot-parameters-modify-more-info.xml b/glues/kernel-boot-parameters-modify-more-info.xml new file mode 100644 index 000000000..f8145e839 --- /dev/null +++ b/glues/kernel-boot-parameters-modify-more-info.xml @@ -0,0 +1,47 @@ + + + + + %entities; +]> + + + For more information + + + + + + + + + + Detailed information about the parameters in the &grub; configuration + file for &productname; is available at + . + + + + + Detailed information of boot parameters for &productname; is available + at + . + + + + diff --git a/tasks/kernel-boot-parameters-modify-permanent.xml b/tasks/kernel-boot-parameters-modify-permanent.xml new file mode 100644 index 000000000..4f45c1a64 --- /dev/null +++ b/tasks/kernel-boot-parameters-modify-permanent.xml @@ -0,0 +1,116 @@ + + + + + %entities; +]> + + + + + + + Permanently modifying kernel boot parameters + + + + + + + To change kernel boot parameters persistently for all subsequent boot + processes, edit the kernel parameters using &yastcc;. + + + +
+ Introduction + + Permanent or persistent changes are helpful if a change needs to be + applied for all subsequent boot processes. Your changes are applied to + all subsequent boot processes, unless modified further. + +
+
+ Requirements + + To change kernel boot parameters for all subsequent boot processes, you + should have root or equivalent administrative + privileges. + +
+
+ Permanently modify kernel boot parameters using &yastcc; + + As an example of modifying kernel boot parameters persistently for all + subsequent boot process, we disable the splash screen that you can see + during the boot. + + + + Before modifying kernel boot parameters, create a copy of the existing + stable configuration somewhere outside of your system. If the boat + loader gets corrupted and your system fails to boot, or you face + problems after booting your system, the back up helps you compare and + restore the parameters to the last known working configuration. + + + + + + Log in to your system as root, or switch to a user with equivalent + administrative priviliges after logging in to your system. + + + + + In your running system, open a root shell and run the following + command: + +&prompt.root;yast bootloader + + Alternatively, open the &yastcc; application and navigate to + System > Boot Loader. + + + + + Under the Kernel Parameters tab, edit the string + for the Optional Kernel Command Line Parameter + field. + +splash=silent resume=/dev/disk/by-uuid/69ff0e54-23a7-4ba8-8983-5a29c54ffa5e quiet security=apparmor crashkernel=301M,high crashkernel=72M,low + + As you can see, the string splash=silent is + printed. Remove splash=silent from the string. + + + + + Select OK to save the boot loader configuration. + + + + + Reboot. You should see that the splash screen does not appear. + + + +
+
+ Summary + + After executing the procedure and rebooting the system, you will not + observe any splash screen for all subsequent boot process unless the + kernel parameter configurartion is modified again. + +
+
diff --git a/tasks/kernel-boot-parameters-modify-temporary.xml b/tasks/kernel-boot-parameters-modify-temporary.xml new file mode 100644 index 000000000..26ec994ab --- /dev/null +++ b/tasks/kernel-boot-parameters-modify-temporary.xml @@ -0,0 +1,121 @@ + + + + + %entities; +]> + + + + + + + Temporarily modifying kernel boot parameters + + + + + + + To change kernel boot parameters on an experimental basis only for the + upcoming boot process, edit the options available on the &grub; boot + screen. + + + +
+ Introduction + + Temporary changes are helpful to test the effect of modifying kernel boot + parameters. After you have changed the kernel boot parameters, the + changes are applied for the upcoming boot process. However, it does not + survive subsequent boot processes. + +
+
+ Requirements + + To modify kernel boot parameters only for the upcoming boot process, + there are no strict requirements. However, you must know the parameters + you want to modify and their effect. + +
+
+ Temporarily modify kernel boot parameters using the &grub; boot menu + + As an example of modifying kernel boot parameters for the upcoming boot + process, we disable the splash screen that you can see during the boot. + + + + Before modifying kernel boot parameters, create a copy of the existing + stable configuration somewhere outside of your system. If the boat + loader gets corrupted and your system fails to boot, or you face + problems after booting your system, the back up helps you compare and + restore the parameters to the last known working configuration. + + + + + + Switch on your computer to start the boot process. + + + + + In the &grub; boot screen, highlight the entry you want to modify + using the arrow keys and + . + + + + + Press the E key. You are presented with an editor + and the content of the selected boot entry. It looks similiar to the + following: + +setparams '&productname; &productnumber;' + ... + ... + echo 'Loading Linux KERNEL_VERSION ...' +linux /boot/vmlinuz-KERNEL_VERSION +root=UUID=56d052b3-9148-4161-8065-3d97378d5783 ${extra_cmdline} splash=silent resume=/dev/disk/by-uuid/69ff0e54-23a7-4ba8-8983-5a29c54ffa5e +quiet security=apparmor crashkernel=301M,high crashkernel=72M,low mitigations=auto + + + + + Search for the string splash=silent and remove it. + + + + + To boot the entry, press F10 or + X . + + + To discard the changes and start anew, press the + key. + + + +
+
+ Summary + + After executing the procedure and continuing with the boot process, you + will not observe any splash screen for the current boot process. On the + next boot, the splash screen will reappear. + +
+
diff --git a/tasks/kernel-boot-parameters-modify-troubleshoot.xml b/tasks/kernel-boot-parameters-modify-troubleshoot.xml new file mode 100644 index 000000000..4d0b00b74 --- /dev/null +++ b/tasks/kernel-boot-parameters-modify-troubleshoot.xml @@ -0,0 +1,68 @@ + + + + + %entities; +]> + + + + + + + Troubleshooting modified kernel boot parameters + + + + + While modifying kernel boot parameters, challenges may arise, potentially + leading to system instability or boot failure. A few troubleshooting + steps to address such issues are listed in this section. + + + +
+ Common problems after modifying kernel boot parameters + + + + Incorrect parameter + + Ensure that the parameters' syntax and spelling are accurate, + correcting any mistakes or typos in the configurations. + + + + + + Boot failure + + If the system fails to boot, use a previous stable snapshot to + rescue the system and then revert the changes to restore system + functionality. + + + + + + System instability + + If the system exhibits instability or unexpected behavior, undo the + changes made to the kernel boot parameters and reevert to the last + working configuration. It is also recommended to closely monitor + the system for stability. + + + + +
+
diff --git a/xml/task-modify-kernel-boot-parameters.xml b/xml/task-modify-kernel-boot-parameters.xml deleted file mode 100644 index 86de095fd..000000000 --- a/xml/task-modify-kernel-boot-parameters.xml +++ /dev/null @@ -1,306 +0,0 @@ - - - - - - - %entities; -]> - - - - - - - - - -
- - - Modifying kernel boot parameters - - - https://bugzilla.suse.com/enter_bug.cgi - Smart Docs - Documentation - thomas.schraitle@suse.com - - no - - - -
- - - Environment - - This document applies to the following products and product versions: - - - - &sles; 15 SP5, 15 SP4, 15 SP3, 15 SP2, 12 SP5 - - - &sles4sap; 15 SP5, 15 SP4, 15 SP3, 15 SP2, 12 SP5 - - - &sleha; 15 SP5, 15 SP4, 15 SP3, 15 SP2, 12 SP5 - - - &slehpc; 15 SP5, 15 SP4, 15 SP3, 15 SP2 - - - &sled; 15 SP5 - - - &slert; 15 SP5 - - -
- -
- Introduction - - The &suselinux; kernel provides everything to ensure - stable operation on your computer. However, in some cases it is necessary - to provide boot parameters to influence the boot process for &grub; or modify - the behaviour of the kernel itself. - - - For example, you can control the Advanced Configuration and - Power Interface (ACPI) settings, define the output console, - enable debugging, and many more. - - - There are two methods to modify your kernel boot parameters: - - - - - Temporarily - - After you have changed the kernel boot parameters, the change will - be applied for the upcoming boot process. However, it does not survive subsequent - boot processes. - - - - - - Permanently - - Your change is applied for each boot process. - - - - - - As an example, we will disable the splash screen that you can see during the boot. - -
- -
- Requirements - - - - To only temporarily modify the kernel boot parameters, no prerequisites required. - - - - - To permanently modify the kernel boot parameters, you need write access - to your root partition and the /etc - directory. - - - -
- -
- Temporarily modifying kernel boot parameters - - Test a kernel boot parameter, a temporary change is helpful. - Such a change is only applied for the current boot process, not for any - subsequent boot processes. - - - - To temporarily disable the splash screen, proceed as follows: - - - - Switch on your computer. The boot process will start. - - - - - In the &grub; boot screen, highlight the entry you want to modify using - the arrow keys and . - - - - - Press the E key. You will be presented with an editor - and the content of the selected boot entry. It will look similiar to the following: - - setparams '&productname; &productnumber;' - # ... some lines pruned ... - echo 'Loading kernel ...' - linuxefi /boot/vmlinuz-5.3.18-lp152.87-default root=UUID=0dfcff43-7a61-4ecd-8df5-8dc56ee3d9f2 splash=silent resume=/dev/disk/by-uuid/0399f92e-5ed4-48c8-9db0-11e52c5cb0cd quiet mitigations=auto - - - - - Search for the string splash=silent and remove it. - - - - - To boot the entry, press F10 or - - X - . - - - To discard the changes and start anew, press the key. - - - - - During reboot, the splash screen is not shown. - -
- -
- Permanently modifying kernel boot parameters - - If a change needs to be applied for every boot process, use this procedure. - - - - To permanently disable the splash screen, proceed as follows: - - - - In your running system, open a shell and view the current command line used by the - Linux kernel: - &prompt.root;cat /proc/cmdline -BOOT_IMAGE=/boot/vmlinuz-5.3.18-59.19-default root=UUID=7e957c2e-fd30-4160-a771-dbc1bc679cf2 splash=silent quiet mitigations=auto - - As you can see, the string splash=line is printed. - We will remove it for the next boot. - - - - - Open the file /etc/default/grub. - - - - - Look for the line GRUB_CMDLINE_LINUX_DEFAULT=. - Remove the string splash=line from this line and save the file. - - - - Run: - toms 2021-08-27: not sure if to use update-bootloader or grub2-mkconfig - &prompt.root;update-bootloader --refresh - - - - - Reboot. You should see that the splash screen does not appear. - - - After your computer has successfully booted, log in and check your boot - commandline: - - &prompt.root;cat /proc/cmdline -BOOT_IMAGE=/boot/vmlinuz-5.3.18-59.19-default root=UUID=7e957c2e-fd30-4160-a771-dbc1bc679cf2 mitigations=auto - - There is no splash string anymore. - - - -
- - - - - - - -
- Related topics - - - - - - - -
-