201: Linux Kernel

201.1 Kernel components (weight: 2)

Candidates should be able to utilise kernel components that are necessary to specific hardware, hardware drivers, system resources and requirements. This objective includes implementing different types of kernel images, understanding stable and longterm kernels and patches, as well as using kernel modules. Key Knowledge Areas:

  • Kernel 2.6.x, 3.x and 4.x documentation

The following is a partial list of the used files, terms and utilities:

  • /usr/src/linux/

  • /usr/src/linux/Documentation/

  • zImage

  • bzImage

  • xz compression

The Kernel Source Tree and Compressed Kernel Images

  • The Kernel Source Tree: The default location for the kernel source tree is in /usr/src (for CentOS, this is /usr/src/kernels). The kernel documentation is in the Documentation directory within the source tree. The 00-INDEX in the documentation directory gives list of the various files and directories as well as a short description.

The two main types of kernel images are zImage and bzImage. Once compiled, the compressed image is copied to the boot directory and renamed to vmlinuz followed by the kernel version and architecture.

  • zImage was used on older systems and designed to fit within the limited amount of memory that was available (the first 640 KB, AKA low memory). The image was compressed down to 512 KB using gzip compression.

  • bzImage stands for big zImage and takes advantage for the higher memory available (around 1 MB, AKA high memory). This change happened around version 2 of the Linux kernel and by version 2.6 bzip2 was the standard compression used.

[root@linuxmaster ~]# ls /boot/
...
vmlinuz-3.10.0-1160.71.1.el7.x86_64
vmlinuz-3.10.0-1160.76.1.el7.x86_64
...

  • xz Compression: As of 2013, kernel.org started providing kerel archives in xz compression rather than bzip2 (older archives will remain in bzip2). xz used the LZMA2 compression algorithm and has become a standard beacause of its efficiency and lower compression ratio.

201.2 Compiling a Linux kernel (weight: 3)

Candidates should be able to properly configure a kernel to include or disable specific features of the Linux kernel as necessary. This objective includes compiling and recompiling the Linux kernel as needed, updating and noting changes in a new kernel, creating an initrd image and installing new kernels.

Key Knowledge Areas:

  • /usr/src/linux/

  • Kernel Makefiles

  • Kernel 2.6.x, 3.x and 4.x make targets

  • Customize the current kernel configuration.

  • Build a new kernel and appropriate kernel modules.

  • Install a new kernel and any modules.

  • Ensure that the boot manager can locate the new kernel and associated files.

  • Module configuration files

  • Use DKMS to compile kernel modules.

  • Awareness of dracut

The following is a partial list of the used files, terms and utilities:

  • mkinitrd

  • mkinitramfs

  • make

  • make targets (all, config, xconfig, menuconfig, gconfig, oldconfig, mrproper, zImage, bzImage, modules, modules_install, rpm-pkg, binrpm-pkg, deb-pkg)

  • gzip

  • bzip2

  • module tools

  • /usr/src/linux/.config

  • /lib/modules/kernel-version/

  • depmod

  • dkms

Installing a Linux Kernel and Kernel Modules

# Compile the Linux Kernel
make menuconfig
make bzImage

# Building and Installing Kernel Modules
make modules
make modules_install

# Installing the Kernel and Generating the initramfs
cp /usr/src/kernel_tree/arch/x86/boot/bzImage /boot
mv bzImage kernel_image

mkinitrd initrd_image kernel_version #CentOS
mkinitramfs -o initrd_image kernel_version #Ubuntu

Understanding Make Targets and Associated Utilities

make will execute the commands in the makefile to one or more target names. If the makefile isn't provided, then the make command will look for the makefiles starting with gnumakefile, makefile, and Makefile (Makefile is the suggested usage)

TargetPurpose

all

Builds all targets marked with an asterisk

config

Update current config utilizing a line-oriented program

xconfig

Update current config utilizing a ncurses menu-based program

menuconfig

Update current config utilizing a menu-based program

gconfig

Update current config utilizing a GTK+ based frontend

oldconfig

Update current config utilizing a provided .config as base

mrproper

Remove all generated files + config + various backup files

zImage

Compressed kernel image (arch/x86/boot/zImage)

bzImage

Compressed kernel image (arch/x86/boot/bzImage)

modules

Build all modules

modules_install

Install all modules to INSTALL_MOD_PATH (default: /)

rpm_pkg

Build both source and binary RPM kernel packages

binrpm_pkg

Build only the binary kernel RPM package

dep_pkg

Build both source and library deb kernel packages

  • depmod: depmod is short for dependency modules and is used to generate a dependency list file, modules.dep, and associated map files. depmod analyzes the /lib/modules/kernel_version directory and creates the dependency file modules.dep, as well as a binary hash version called modules.dep.bin. Another important file created by depmod is modules.symbols (and modules.symbols.bin). This file contains a dependency list of symbols - uniqe service provided by modules - that can be used by other modules.

[root@linuxmaster ~]# ls -n /path/to/your-kernel-module.ko /lib/modules/`uname -r`

[root@linuxmaster ~]# depmod -a

  • dkms: Dynamic Kernel Module Support (DKMS) provides a framework for generating kernel modules whose sources generally reside outside of the kernel source tree.

Prepare a module for DKMS:

  • Download and extract the kernel module

  • Create or modify the dkms.conf file

  • Copy the kernel module source code to /usr/src

Add, build, and install with DKMS:

dkms add -m <MODULE-NAME>

dkms build -m <MODUKLE-NAME> -v <MODULE-VERSION>

dkms install -m <MODULE-NAME> -v <MODULE-VERSION>

201.3 Kernel runtime management and troubleshooting (weight: 4)

Candidates should be able to manage and/or query a 2.6.x, 3.x, or 4.x kernel and its loadable modules. Candidates should be able to identify and correct common boot and run time issues. Candidates should understand device detection and management using udev. This objective includes troubleshooting udev rules.

Key Knowledge Areas:

  • Use command-line utilities to get information about the currently running kernel and kernel modules.

  • Manually load and unload kernel modules.

  • Determine when modules can be unloaded.

  • Determine what parameters a module accepts.

  • Configure the system to load modules by names other than their file name.

  • /proc filesystem

  • Content of /, /boot/ , and /lib/modules/

  • Tools and utilities to analyze information about the available hardware

  • udev rules

The following is a partial list of the used files, terms, and utilities:

  • /lib/modules/kernel-version/modules.dep

  • module configuration files in /etc/

  • /proc/sys/kernel/

  • /sbin/depmod

  • /sbin/rmmod

  • /sbin/modinfo

  • /bin/dmesg

  • /sbin/lspci

  • /usr/bin/lsdev

  • /sbin/lsmod

  • /sbin/modprobe

  • /sbin/insmod

  • /bin/uname

  • /usr/bin/lsusb

  • /etc/sysctl.conf, /etc/sysctl.d/

  • /sbin/sysctl

  • udevmonitor

  • udevadm monitor

  • /etc/udev/

Working with Kernel Modules

  • uname: A command line utility that prints basic information about the system. The most common use is to determine the processor architecture, the system hostname, and the kernel version of the system.

Without any options, uname prints kernel name as if the -s option were used.

uname [OPTIONS]
OptionDescription

-a

Print all information

-s

Print the kernel name

-n

Print the network node hostname

-r

Print the kernel release

-v

Print the kernel version

-m

Print the machine hardware name

-p

Print the processor type or "unknown"

-i

Print the hardware platform or "unknown"

-o

Print the operation system

  • dmesg: Print or control the kernel ring buffer. By default, it shows all the messages in the kernel ring buffer.

dmesg [OPTIONS]
OptionDescription

-C

Clear the ring buffer

-c

Clear the ring buffer after printing the contents

-f

Restrict the output to a give list of facilities

-H

Enable human-readable format

-k

Print kernel messages

-l

Restrict output to the given list of levels

-T

Print human-readable timestamps

-u

Print userspace messages

  • lsmod: A trivial program that nicely formats the contents of the /proc/modules file, showing what kernel modules are currently loaded.

  • modinfo: Shows information about a kernel module. By default, modinfo lists each attribute of the module in a filename: value format. If the module name is not a filename, then /lib/modules/kernelversion is searched.

modinfo -O -F field -k kernel modulename [filename]
OptionDescription

-O

Use ASCII zero characters to separate field values instead of new lines

-F

Only print field value specified

-k

Provide information about a kernel other than the running one

  • insmod: A simple program to insert a kernel module into the Linux kernel. It is recommended to use modprobe, which is a more sophisticated command.

insmod [FILENAME] [MODULE_OPTIONS]

  • rmmod: A simple program to remove a module from the Linux kernel. It is recommended to use modprobe with the -r option instead.

rmmod [OPTIONS] [MODULE_NAME]
OptionDescription

-v

Use verbose output

-f

Force the removal of a module

-w

Wait until the module is not in use

-s

Send errors to syslog instead of the standard error

  • modprobe: A program used to add and remove modules from the Linux kernel. modprobe intelligently adds and removes modules by considering module dependencies. Configuration added to /etc/modprobe.d/ or /etc/modprobe.conf are considered when the command is executed.

modprobe [OPTIONS] [MODULE_NAME] [MODULE_PARAMERERS]
OptionDescription

-v

Use verbose output

-C

Override the default configuration directory/file

-n

Perform a dry run

-r

Remove a module

-w

Block new requests to a module and wait until it is available

-f

Attempt to force an insert or a remove

-D

List the dependencies of a module

-o

Attempt to rename a module

Module Configuration Files

  • /lib/modules/kernel-version/module.dep: List the dependencies for every module in the directories under /lib/modules/kernel_version. This file is used by modprobe to know the order in which to load modules.

  • /etc/modules and /etc/modules-load.d/modules.conf and /etc/modules.conf: Used to configure kernel modules to load at boot. The configuration file(s) should contain a list of kernel module names to load, separated by newlines. Empty lines and lines beginning with # or ; are ignored.

  • /etc/modprobe.d and /etc/modprobe.conf: The configuration directory/file for modprobe. The format of this configuration is one command per line with ‘\’ at the end of the line. Blank lines and lines beginning with ‘#’ are ignored.

Commands:

  • alias: Give alternate names for modules

  • options: Add options to the module when it is inserted into the kernel

  • install: run a shell command instead of inserting a module as normal

  • remove: run a shell command when modprobe -r is invoked rather than removing a module

  • blacklist: ignore a particular module’s internal aliases

Understand the /proc Filesystem and the Device Filesystem

  • The proc Filesystem: A virtual filesystem that gets created and mounted during boot time. It presents information about the process and other system-related information. Processes, for which the filesystem is named, are represented by numbered directories that correlate with their PID. System and kernel-level parameters can be changed by manually editing files within the /proc directory or by using the sysctl utility. These changes are only effective for the current runtime and will not persist through a reboot.

[root@linuxmaster ~]# ls -ld /proc/* | awk ‘{print $9}’
/proc/1
/proc/10
/proc/1719
…
/proc/cpuinfo
/proc/devices
/proc/driver
…

  • sysctl: Used to configure kernel parameters at runtime and to display the current values. Available parameters can be found in /proc/sys/. sysctl settings added to /etc/sysctl.conf or /etc/sysctl.d/ will be applied on system boot. Configuration files added to /etc/sysctl.d/ should end with “.conf” and be prefixed with a number based on priority. The higher the prefix number the greater the priority.

sysctl [options] [variable[=value]]
OptionDescription

-a

Display all value currently available

-w

Change a sysctl settings

-p

Load a sysctl settings from a file

-n

Print names without names

-N

Print names without values

  • The Device Filesystem: Contains files for every device of which the system is aware and special device files that are used by the system. Some examples of this are urandom, zero, and null. The kernel device manager, udev, continually probe the system to check for connected devices and creates a device file when one is detected. Udev rules end with .rules an extension and determine how to identify devices and assign names to them. These rules are located in /etc/udev/rules.d/ and /lib/udev/rules.d/.

  • udevadm monitor: Listen to the kernel uevents and events are sent out by a udev rule and prints the devpath of the event to the console. This command replaces the now deprecated udevmonitor utility

udevadm monitor [options]
OptionDescription

-k

Print kernel uevents

-u

Print udev event after rule processing

-p

Also print the properties of the event

Analyzing Information about Available Hardware

  • lspci: A utility for displaying information about Peripheral Component Interconnect (PCI) buses in the system and the devices connected to them. By default, lspci shows a brief list of devices. At more verbose levels, the output is only useful to those who are very familiar with PCI.

lspci [options]
OptionDescription

-m

Dump data in a backward-compatible, machine-readable format

-mm

Dump data in a machine-readable format

-t

Display data in a tree-like diagram

-v

Increase verbosity (-vv and -vvv for more)

-k

Show kernel drivers handling each device and modules that are capable of handling it

-n

Show PCI vendor and devices codes as numbers

  • lsusb: A utility for displaying information about USB buses in the system and the devices connected to them.

lsusb [options]
OptionDescription

-v

Increase verbosity

-s

Show devices specified with bus and/or devnum provided

-d

Show devices specified with vendor and product ID provided

-t

Display USB device hierarchy as a tree

  • lsdev: Displays information about installed hardware. lsdev gathers this information from the interrupts, ioports, and dma files in the /proc directory. There are no command line options for this command.

Commands and Notes

Sample Questions

1. What command prints information about and controls the kernel ring buffer?

2. What are the two main types of compressed kernel images? (Choose two.)

3. What is the utility used to generate modules whose source resides outside of the main kernel source tree?

4. What command is used to generate a compressed kernel image?

5. What command is used to configure kernel parameters at runtime?

6. What is the default location for the kernel source tree?

7. What are accepted names for the makefile? (Choose all that apply.)

8. What command intelligently adds and removes modules from the kernel?

9. Which of the following commands are used to generate the initramfs image? (Choose two.)

10. What command is used to monitor kernel uevents?

11. What option for lspci shows kernel drivers handling each device and modules that are capable of handling it?

12. What command displays information about installed hardware?

13. Which part of a Linux system manages system memory?

14. What is the area on the hard disk called that is used as memory storage?

15. What method does Linux use to load device drivers into the kernel?

16. Which kernel file type is used to boot the Linux system?

17. What type of release can you use to upgrade an existing kernel to a newer version?

18. Which make utility target uses text-based questions to configure the kernel?

19. Which make utility target uses a graphical interface to configure the kernel?

20. Which make utility target should you use to remove any old object files from a previous compile?

21. Which make utility target is commonly used to generate a compressed kernel binary file?

22. Which program should you use to create an initial RAM disk for a Debian-based system?

23. Which command should you use to list all of the installed modules?

24. Which command should you use to install a module if you don’t know its filename?

26. Which command should you use to display information about USB devices installed on the system?

27. Which option in the lsusb command displays detailed information about the USB devices?

28. Which type of hardware devices can you connect to the Linux system as it’s running?

29. What program does Linux use to detect hotplug devices and load the appropriate modules?

30. Where are the udevd configuration settings stored?

31. Where are the udevd rules stored?

32. Where is the dynamic pseudo-directory the kernel creates to peek at kernel settings and performance statistics located?

33. What command allows you to change kernel settings during runtime?

34. Which of the following terms are used to describe 3.x kernel releases? (Choose TWO correct answers.)

35. How can the kernel parameter for the maximum size of the shared memory segment (shmmax) be changed to 2GB (2147483648 Bytes) on a running system? (Choose TWO correct answers.)

36. What is the correct parameter to pass to the kernel at boot time to force it to use only one of the available processors?

37. Which commands are used to load modules into the Linux kernel? (Choose TWO correct answers.)

38. What is a key difference between a zImage and bzImage kernel image?

39. Which of the following command sequences can be used to extract files contained in a initramfs file (/boot/initramfs) which is used by the kernel at boot time?

Description:

  1. cp /boot/initramfs /tmp/initramfs.gz - This command copies the initramfs file from the /boot directory to /tmp and renames it to initramfs.gz. Note that this step assumes the initramfs file is compressed with gzip. If it's not a gzipped file, the .gz extension shouldn't be added.

  2. gunzip /tmp/initramfs.gz - This command decompresses the file initramfs.gz. After decompression, the file will be named initramfs in the /tmp directory.

  3. mkdir /tmp/initramfs.dir - This creates a new directory where the contents of the initramfs file will be extracted.

  4. cd /tmp/initramfs.dir - This changes the current working directory to the newly created directory.

  5. cpio -i < /tmp/initramfs - This command uses cpio to extract the contents of the initramfs file into the current directory (/tmp/initramfs.dir). The -i option stands for "extract".

40. On a server running the 3.4.50-11 Linux kernel, which file in the /boot directory contains the kernel configuration parameters?

Description: In a Linux system, the file that contains the kernel configuration parameters is typically named with the config- prefix followed by the kernel version. This file is located in the /boot directory. Based on the options you've provided and the kernel version you mentioned (3.4.50-11), the correct file would be: config-3.4.50-11

41. Which archive format is used to create an initramfs image?

42. What information does the file modules.dep provide?

43. What is the purpose of the command udevadm monitor?

44. How is the source code for the main Linux kernel modules distributed?

45. Which option to the update-rc.d command will cause the removal of all symlinks to /etc/rcX.d/*test2 even when the script /etc/init.d/test2 still exists?

Description: The -f option stands for "force". When you use update-rc.d -f test2 remove, it forces the removal of all symbolic links to the /etc/init.d/test2 script from the /etc/rcX.d directories regardless of whether the /etc/init.d/test2 script still exists.

46. Which of the following files will be looked for and used by GNU make, if one of them exists, unless a different file is specified on the command line when trying to compile software from source code? (Choose TWO correct answers.)

47. Before compiling a new kernel , what needs to be done?

Description: Configuring the kernel options is a critical step in the kernel compilation process. This involves selecting the necessary modules, features, and settings that the new kernel will support. This configuration can be done using tools like make menuconfig, make xconfig, or make gconfig in the Linux kernel source directory. The configuration process creates a .config file, which is used by the make command during the compilation process.

48. That script is included with the source of the kernel to fix a kernel ?

Description: In the context of Linux kernel development and maintenance, the patch utility is used to apply changes to the kernel source code. These changes are often distributed in the form of "patch files," which contain the differences between one set of files and another. When developers fix bugs or add features, they often do so by creating a patch file that can be applied to the kernel source using the patch command.

49. What command would you use to apply a diff file to an original?

Description: This command uses the patch utility, which is specifically designed for applying diff files. The diff file contains the differences between files and is applied to the original files to update them. The syntax patch < diff-file means that the patch command takes the contents of the diff file as input.

50. After configuring a new 2.4 series kernel , all dependencies, such as included files, need to be created. How can this be achieved?

Description: The make dep command was used specifically with older Linux kernel series like 2.4 to create dependencies. This command ensures that all the necessary headers and files are properly linked based on the configuration choices made.

51. What two archiving formats are used to create an initramfs image?

52. After unpacking the source code for a Linux kernel, what is the first make command that should be executed, which will delete any current configuration and all generated files? This command will ensure that the maintainer does not leave inappropriate files in the kernel file.

Description: The make mrproper command is used to thoroughly clean the kernel source tree. It removes not only the compiled binaries and object files (which make clean does) but also the configuration files and other generated files that might not be needed for a fresh start. This command ensures that you start with a clean state, which is particularly important when compiling a new kernel or switching between different kernel versions.

53. What script, in the linux / scripts directory , can be used to add upgrades or updates to the 2.6.xx kernel source code?

Description: The patch-kernel script is designed to apply a series of patch files to the Linux kernel source. It automates the process of updating or upgrading the kernel source code with new patches, which are often released for bug fixes, security updates, and new features.

54. You have finished updating and resolving dependencies on some source code. What command should you run before recompiling the code in binary format?

Description: The purpose of make clean is to remove all files that were generated during previous builds. This ensures that you start the compilation with a clean slate, which is particularly important after updating source code or dependencies, as old object files or binaries might interfere with the new build process.

55. What tool can be used to control the behavior of runtime of udev?

Description: udevadm is the command-line utility provided for interacting with the udev Linux device manager. It allows for managing the runtime behavior of the udev system, including triggering events, querying udev database, monitoring udev events, and controlling the udev daemon.

56. Which command can be used to view the kernel messages created from the boot time so far?

57. Why mkinitrd was deprecated in favor of mkinitramfs from the series Kermel 2.6? (Select 2 correct answers).

58. A precompiled module has been moved to /lib/modules/<kernel-version>, but modprobe -a <module-name> fails to load it. What needs to be done to use this module?

Description: The depmod command creates a module dependency file (modules.dep and other map files) in the /lib/modules/<kernel-version> directory. This file is used by modprobe to automatically load the necessary modules and their dependencies. Running depmod ensures that the system is aware of the new module and its dependencies, making it possible for modprobe to load the module successfully.

59. To restore a kernel source to its previous, unpatched version, which of the following commands could be used?

Description: The -R option with the patch command reverses the patching process. It essentially "undoes" the changes made by a patch. When you apply a patch using patch, it makes changes to the source code based on the contents of the patch file. Using patch -R with the same patch file will revert those changes, restoring the source code to its previous state.

60. If the current directory is /root and the kernel source is located in /usr/src/linux, which of the following commands should be used to apply the /tmp/foopatch patch?

61. A 2.6.9-ac1 kernel would be:

62. What command should be used to find out which PCI devices can be seen, without consulting the kernel?

Description: The lspci command lists all PCI devices. The -v flag (for "verbose") provides detailed information about each device. This command reads the device information directly from the PCI configuration space, so it does not rely on the kernel's view of the devices.

63. User Joseph successfully extracted and compiled a program from source code. Installing the Binaries produces errors. What is the most likely reason?

64. The structure of the official Linux kernel can be classified as:

Description: The Linux kernel is known as a monolithic kernel. This means it operates in a single large process running entirely in a single address space. It's distinguished from micro-kernel systems where the kernel is broken down into separate processes known as servers. The terms "stable" and "multitasking" are characteristics or features of an operating system, but they do not describe its structural classification.

65. What is the correct Linux kernel version numbering format?

66. What do the suffixes added to the kernel version number represent?

67. Where can the official kernel version specific documentation be found?

68. What commands can be used to generate an Initial Ramdisk?

69. Which command can be used to configure the Linux kernel?

70. The uname -r command reports:

71. The correct way to load the ehci_hcd module and its dependencies is:

72. What type of compression is used in a zImage kernel?

73. What information is not normally provided by the modinfo command? Select everything that applies.

74. After compiling a new kernel, which of the following is a valid filename for the compressed kernel?

Description: vmlinux is the uncompressed kernel image.

75. Which of the following commands will show the status of the running kernel?

76. What is the conventional name for a Linux kernel initially compiled and bootable on an x86 system?

77. In which directory can you look for information about the options that can be applied to your computer's Ethernet driver module?

77. What kind of kernel image was largely abandoned on x86 computers in favor of the bzImage format?

78. Which of the following commands, when typed in /usr/src/linux after configuring the kernel, compiles the main Linux kernel file and its modules?

79. Which of the following kernel features should you compile in the main kernel file for an x86-64 disk-based installation to simplify system startup? (Select 2 responses).

80. You have compiled and installed a new kerne , version 2.6.35.4. You now want to prepare an initial RAM disk. Which of the following commands will do this, depending on your distribution? (Select 2 options).

81. You downloaded the patch file - 2.6.35.4.bz2. What program will you use as part of the patching operation to handle the compression of this file?

82. Which of the following commands must you enter to configure a Linux kernel using an interactive text mode tool?

83. You have configured and compiled your new kernel, version 2.6.35.4. Now you type make modules_install. Where can you expect to find the module files?

84. In which file in the Linux kernel source tree are configuration options stored?

Description: The .config file in the root of the Linux kernel source tree holds the configuration options for the kernel. This file is generated when you run a kernel configuration tool like make menuconfig, make xconfig, or make config, and it reflects the choices made for various kernel features and modules. The other file names listed are not standard for storing kernel configuration options.

85. You found a kernel module for your network card, but you don't know what parameters to use. Which command can provide you with this information?

86. Which of the following commands will load a kernel module, along with all necessary dependency modules?

87. Which command should load the msdos.o module and all its dependencies?

88. Which command will remove a kernel module?

89. You have just added new modules to the system. Which command should you run to rebuild the modules.dep file?

90. Which of the following correctly describes the relationship between depmod and modprobe?

Description: depmod is used to create a dependency file (typically named modules.dep) which lists the dependencies for each module. This file is then used by modprobe to understand which modules need to be loaded when a particular module is requested, ensuring that all necessary dependencies are loaded automatically. They have a complementary relationship, but they do not replace each other, as each serves a distinct purpose in the management of kernel modules.

91. Which option of the depmod command allows you to print a list of all unresolved symbols?

92. Which of the following commands loads the module file into the kernel and changes any symbols that are defined on the command line?

93. What option of the insmod command can be used to force the module to load even if problems are encountered?

94. Which option in the rmmod command specifies that all output should be sent to the syslog?

95. Which utility examines the object module_file file associated with a kernel module and displays all the information it can collect?

96. Which modprobe option specifies the loading of all corresponding modules instead of stopping after the first successfully loaded module is loaded?

96. Which modprobe option allows you to define "autoclean" on loaded modules?

97. Which parameter of the uname command can be used to display the kernel version?

98. Which parameter of the uname command can be used to display the machine type (Hardware / Architecture)?

Last updated