Which of the following files holds the configuration information for GRUB?
This file contains the configuration of the GRUB 2 menu items. It replaces ### BEGIN /etc/grub.d/90_persistent ###0. Show
### BEGIN /etc/grub.d/90_persistent ###1 This optional file is directly sourced by ### BEGIN /etc/grub.d/90_persistent ###3. ### BEGIN /etc/grub.d/90_persistent ###4 This file controls the user settings of GRUB 2 and usually includes additional environmental settings such as backgrounds and themes. Scripts under### BEGIN /etc/grub.d/90_persistent ###5 The scripts in this directory are read during execution of the command ### BEGIN /etc/grub.d/90_persistent ###0. Their instructions are integrated into the main configuration file ### BEGIN /etc/grub.d/90_persistent ###7. ### BEGIN /etc/grub.d/90_persistent ###8 This configuration file holds some basic settings like the boot loader type and whether to enable UEFI Secure Boot support. ### BEGIN /etc/grub.d/90_persistent ###9, These configuration files contain architecture-specific options. GRUB 2 can be controlled in various ways. Boot entries from an existing configuration can be selected from the graphical menu (splash screen). The configuration is loaded from the file ### END /etc/grub.d/90_persistent ###1 privileges to edit them.Note: Activating Configuration Changes After having manually edited GRUB 2 configuration files, you need to run ### BEGIN /etc/grub.d/90_persistent ###0 to activate the changes. However, this is not necessary when changing the configuration with YaST, because YaST will automatically run this command. The graphical splash screen with the boot menu is based on the GRUB 2 configuration file Every time the system is booted, GRUB 2 loads the menu file directly from the file system. For this reason, GRUB 2 does not need to be re-installed after changes to the configuration file. More general options of GRUB 2 belong here, such as the time the menu is displayed, or the default OS to boot. To list all available options, see the output of the following command:
In addition to already defined variables, the user may introduce their own variables, and use them later in the scripts found in the ### END /etc/grub.d/90_persistent ###5 directory. After having edited ### BEGIN /etc/grub.d/90_persistent ###4, update the main configuration file with ### BEGIN /etc/grub.d/90_persistent ###0.Note: Scope All options set in this file are general options that affect all boot entries. Specific options for Xen kernels or the Xen hypervisor can be set via the GRUB_*_XEN_* configuration options. See below for details. ### END /etc/grub.d/90_persistent ###8 Sets the boot menu entry that is booted by default. Its value can be a numeric value, the complete name of a menu entry, or “saved”. ### END /etc/grub.d/90_persistent ###9 boots the third (counted from zero) boot menu entry. (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID0 boots the first submenu entry of the third top-level menu entry. (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID1 boots the menu entry with the title “Example boot menu entry”. (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID2 boots the entry specified by the (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID3 or (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID4 commands. While (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID5 sets the default boot entry for the next reboot only, (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID4 sets the default boot entry until changed. (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID7 lists the next boot entry. (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID8 Waits the specified number of seconds for the user to press a key. During the period no menu is shown unless the user presses a key. If no key is pressed during the time specified, the control is passed to (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID9. 0 first checks whether Shift is pressed and shows the boot menu if yes, otherwise immediately boots the default menu entry. This is the default when only one bootable OS is identified by GRUB 2. 1 If 2 is specified, a countdown timer is displayed on a blank screen when the (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID8 feature is active. (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID9 Time period in seconds the boot menu is displayed before automatically booting the default boot entry. If you press a key, the timeout is cancelled and GRUB 2 waits for you to make the selection manually. 5 will cause the menu to be displayed until you select the boot entry manually. 6 Entries on this line are added at the end of the boot entries for normal and recovery mode. Use it to add kernel parameters to the boot entry. 7 Same as 6 but the entries are appended in the normal mode only. 9 Same as 6 but the entries are appended in the recovery mode only. set superusers="root" password_pbkdf2 root grub.pbkdf2.sha512.10000.9CA4611006FE96BC77A...1 This entry will completely replace the 6 parameters for all Xen boot entries. set superusers="root" password_pbkdf2 root grub.pbkdf2.sha512.10000.9CA4611006FE96BC77A...3 Same as set superusers="root" password_pbkdf2 root grub.pbkdf2.sha512.10000.9CA4611006FE96BC77A...1 but it will only replace parameters of 7. set superusers="root" password_pbkdf2 root grub.pbkdf2.sha512.10000.9CA4611006FE96BC77A...6 This entry specifies the kernel parameters for the Xen guest kernel only—the operation principle is the same as for 6. set superusers="root" password_pbkdf2 root grub.pbkdf2.sha512.10000.9CA4611006FE96BC77A...8 Same as set superusers="root" password_pbkdf2 root grub.pbkdf2.sha512.10000.9CA4611006FE96BC77A...6—the operation principle is the same as for 7. 1 Enables and specifies an input/output terminal device. Can be 2 (PC BIOS and EFI consoles), 3 (serial terminal), 4 (Open Firmware console), or the default 5 (graphics-mode output). It is also possible to enable more than one device by quoting the required options, for example 6. 7 The resolution used for the 5 graphical terminal. Note that you can only use modes supported by your graphics card (VBE). The default is ‘auto’, which tries to select a preferred resolution. You can display the screen resolutions available to GRUB 2 by typing 9 in the GRUB 2 command line. The command line is accessed by typing C when the GRUB 2 boot menu screen is displayed. You can also specify a color depth by appending it to the resolution setting, for example /boot/grub2/grub.cfg 1Set a background image for the 5 graphical terminal. The image must be a file readable by GRUB 2 at boot time, and it must end with the /boot/grub2/grub.cfg 3, /boot/grub2/grub.cfg 4, /boot/grub2/grub.cfg 5, or /boot/grub2/grub.cfg 6 suffix. If necessary, the image will be scaled to fit the screen./boot/grub2/grub.cfg 7If this option is set to ### BEGIN /etc/grub.d/90_persistent ###5 are detected. menu.lst 1If this option is set to For a complete list of options, see the GNU GRUB manual. The scripts in this directory are read during execution of the command ### BEGIN /etc/grub.d/90_persistent ###0. Their instructions are incorporated into /boot/grub2/grub.cfg . The order of menu items in grub.cfg is determined by the order in which the files in this directory are run. Files with a leading numeral are executed first, beginning with the lowest number. menu.lst 6 is run before menu.lst 7, which would run before menu.lst 8. If files with alphabetic names are present, they are executed after the numerically-named files. Only executable files generate output to grub.cfg during execution of grub.cfg 0. By default all files in the ### END /etc/grub.d/90_persistent ###5 directory are executable.Tip: Persistent Custom Content in grub.cfg Because ### BEGIN /etc/grub.d/90_persistent ### and ### END /etc/grub.d/90_persistent ### The A list of the most important scripts follows:
Sets environmental variables such as system file locations, display settings, themes, and previously saved entries. It also imports preferences stored in the ### BEGIN /etc/grub.d/90_persistent ###4. Normally you do not need to make changes to this file. menu.lst 7Identifies Linux kernels on the root device and creates relevant menu entries. This includes the associated recovery mode option if enabled. Only the latest kernel is displayed on the main menu page, with additional kernels included in a submenu. ### BEGIN /etc/grub.d/90_persistent ###01 This script uses ### BEGIN /etc/grub.d/90_persistent ###02 to search for Linux and other operating systems and places the results in the GRUB 2 menu. There are sections to identify specific other operating systems, such as Windows or macOS. menu.lst 8This file provides a simple way to include custom boot entries into ### BEGIN /etc/grub.d/90_persistent ###05 part at the beginning. The processing sequence is set by the preceding numbers with the lowest number being executed first. If scripts are preceded by the same number the alphabetical order of the complete name decides the order. ### BEGIN /etc/grub.d/90_persistent ###1 If you create ### BEGIN /etc/grub.d/90_persistent ###1 and fill it with content, it will be automatically included into /boot/grub2/grub.cfg just after 40_custom at boot time.12.2.4 Mapping between BIOS Drives and Linux Devices #Edit sourceIn GRUB Legacy, the ### BEGIN /etc/grub.d/90_persistent ###09 configuration file was used to derive Linux device names from BIOS drive numbers. The mapping between BIOS drives and Linux devices cannot always be guessed correctly. For example, GRUB Legacy would get a wrong order if the boot sequence of IDE and SCSI drives is exchanged in the BIOS configuration. GRUB 2 avoids this problem by using device ID strings (UUIDs) or file system labels when generating However, if you need to override the GRUB 2's automatic device mapping mechanism, create your custom mapping file ### BEGIN /etc/grub.d/90_persistent ###11. The following example changes the mapping to make ### BEGIN /etc/grub.d/90_persistent ###12 the boot disk. Note that GRUB 2 partition numbers start with ### BEGIN /etc/grub.d/90_persistent ###13 and not with ### BEGIN /etc/grub.d/90_persistent ###14 as in GRUB Legacy. (hd1) /dev/disk-by-id/DISK3 ID (hd2) /dev/disk-by-id/DISK1 ID (hd3) /dev/disk-by-id/DISK2 ID Even before the operating system is booted, GRUB 2 enables access to file systems. Users without root permissions can access files in your Linux system to which they have no access after the system is booted. To block this kind of access or to prevent users from booting certain menu entries, set a boot password. Important: Booting Requires PasswordIf set, the boot password is required on every boot, which means the system does not boot automatically. Proceed as follows to set a boot password. Alternatively use YaST ().
After you reboot, you will be prompted for a user name and a password when trying to boot a menu entry. Enter ### END /etc/grub.d/90_persistent ###1 and the password you typed during the ### BEGIN /etc/grub.d/90_persistent ###19 command. If the credentials are correct, the system will boot the selected boot entry. Where are grub2 configuration files stored?The main Grub 2 configuration file, normally located in the /boot/grub folder, is grub. cfg. It is the product of various scripts and should not normally be edited directly.
Which of the following file extensions are used by the Debian package manager?A file extension. By default, all Debian packages end with . deb file extension.
What is the path to where the journald conf file is located?Journald Configuration. The main configuration file for systemd-journald is /etc/systemd/journald. conf.
Where are scheduled commands stored on Ubuntu Linux systems?Each user profile on the system can have their own crontab where they can schedule jobs, which is stored under /var/spool/cron/crontabs/ . To schedule a job, open up your crontab for editing and add a task written in the form of a cron expression.
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