The GRUB menu.lst file lists the contents of theGRUB main menu. The GRUB main menu lists boot entries for all the OS instancesthat are installed on your system, including Solaris Live Upgrade boot environments.The Solaris software upgrade process preserves any changes that you make tothis file.
Any revisions made to the menu.lst file are displayedon the GRUB main menu, along with the Solaris Live Upgrade entries. Any changesthat you make to the file become effective at the next system reboot. Youcan revise this file for the following reasons:
Grub4dos Menu Lst Manuals
Although you can use the menu.lst file to customizebooting behavior such as booting with the kernel debugger, the preferred methodfor customization is to use the eeprom command. If youuse the menu.lst file to customize, the Solaris OS entriesmight be modified during a software upgrade. Changes to the file would thenbe lost.
You must always use the bootadm command to locatethe GRUB menu's menu.lst file. The list-menu subcommand finds the active GRUB menu. The menu.lst filelists all the operating systems that are installed on a system. The contentsof this file dictate the list of operating systems that is displayed on theGRUB menu. If you want to make changes to this file, see x86: Locating the GRUB Menu's menu.lst File (Tasks).
When booting with GRUB, you can use either a command-line interface(see Command-line interface), or a menu interface (see Menu interface). Using the command-line interface, you type the drivespecification and file name of the kernel manually. In the menuinterface, you just select an OS using the arrow keys. The menu isbased on a configuration file which you prepare beforehand(see Configuration). While in the menu, you can switch to thecommand-line mode, and vice-versa. You can even edit menu entriesbefore using them.
A menu interface listing preset boot commands, with a programmabletimeout, is available. There is no fixed limit on the number of bootentries, and the current implementation has space for several hundred.
A fairly flexible command-line interface, accessible from the menu,is available to edit any preset commands, or write a new boot commandset from scratch. If no configuration file is present, GRUB drops tothe command-line.
GRUB avoids this problem nowadays by using UUIDs or file system labels whengenerating grub.cfg, and we advise that you do the same for anycustom menu entries you write. If the device map file does not exist, thenthe GRUB utilities will assume a temporary device map on the fly. This isoften good enough, particularly in the common case of single-disk systems.
The program grub-mkconfig (see Invoking grub-mkconfig)generates grub.cfg files suitable for most cases. It is suitable foruse when upgrading a distribution, and will discover available kernels andattempt to generate menu entries for them.
grub-mkconfig does have some limitations. While adding extracustom menu entries to the end of the list can be done by editing/etc/grub.d/40_custom or creating /boot/grub/custom.cfg,changing the order of menu entries or changing their titles may requiremaking complex changes to shell scripts stored in /etc/grub.d/. Thismay be improved in the future. In the meantime, those who feel that itwould be easier to write grub.cfg directly are encouraged to do so(see Booting, and Shell-like scripting), and to disable any systemprovided by their distribution to automatically run grub-mkconfig.
The GRUB graphical menu supports themes that can customize the layout andappearance of the GRUB boot menu. The theme is configured through a plaintext file that specifies the layout of the various GUI components (includingthe boot menu, timeout progress bar, and text messages) as well as theappearance using colors, fonts, and images. Example is available in docs/example_theme.txt
However, note that GRUB assumes that your terminal emulator iscompatible with VT100 by default. This is true for most terminalemulators nowadays, but you should pass the option --dumb tothe command if your terminal emulator is not VT100-compatible orimplements few VT100 escape sequences. If you specify this option thenGRUB provides you with an alternative menu interface, because the normalmenu requires several fancy features of your terminal.
This is the core image of GRUB. It is built dynamically from the kernelimage and an arbitrary list of modules by the grub-mkimageprogram. Usually, it contains enough modules to access /boot/grub,and loads everything else (including menu handling, the ability to loadtarget operating systems, and so on) from the file system at run-time. Themodular design allows the core image to be kept small, since the areas ofdisk where it must be installed are often as small as 32KB.
GRUB looks for its configuration file as soon as it is loaded. If oneis found, then the full menu interface is activated using whateverentries were found in the file. If you choose the command-line menuoption, or if the configuration file was not found, then GRUB drops tothe command-line interface.
The command-line interface provides a prompt and after it an editabletext area much like a command-line in Unix or DOS. Each command isimmediately executed after it is entered8. The commands (see Command-line and menu entry commands) are asubset of those available in the configuration file, used with exactlythe same syntax.
Basically, the menu interface provides a list of boot entries tothe user to choose from. Use the arrow keys to select the entry ofchoice, then press RET to run it. An optional timeout isavailable to boot the default entry (the first one if not set), which isaborted by pressing any key.
Commands are available to enter a bare command-line by pressing c(which operates exactly like the non-config-file version of GRUB, butallows one to return to the menu if desired by pressing ESC) or toedit any of the boot entries by pressing e.
If this variable is set, it identifies a menu entry that should beselected by default, possibly after a timeout (see timeout). Theentry may be identified by number (starting from 0 at each level ofthe hierarchy), by title, or by id.
This defines a GRUB menu entry named title. When this entry isselected from the menu, GRUB will set the chosen environment variableto value of --id if --id is given, execute the list ofcommands given within braces, and if the last command in the list returnedsuccessfully and a kernel was loaded it will execute the boot command.
This command sets color of empty areas without text. Text background coloris controlled by environment variables color_normal, color_highlight,menu_color_normal, menu_color_highlight. See Special environment variables.
Load file as a configuration file. If file defines any menuentries, then show a menu containing them immediately. Any environmentvariable changes made by the commands in file will not be preservedafter configfile returns.
Insert keystrokes into the keyboard buffer when booting. Sometimes anoperating system or chainloaded boot loader requires particular keys to bepressed: for example, one might need to press a particular key to enter"safe mode", or when chainloading another boot loader one might sendkeystrokes to it to navigate its menu.
Read file as a configuration file, as if its contents had beenincorporated directly into the sourcing file. Unlike configfile(see configfile), this executes the contents of file withoutchanging context: any environment variable changes made by the commands infile will be preserved after source returns, and the menuwill not be shown immediately.
By default, the boot loader interface is accessible to anyone with physicalaccess to the console: anyone can select and edit any menu entry, and anyonecan get direct access to a GRUB shell prompt. For most systems, this isreasonable since anyone with direct physical access has a variety of otherways to gain full access, and requiring authentication at the boot loaderlevel would only serve to make it difficult to recover broken systems.
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To facilitate system maintenance, the chainloader or configfile command should be used to boot another Linux distribution that provides an "automagic" GRUB configuration mechanism (e.g. Debian, Ubuntu, openSUSE). This allows the distribution to manage its own menu.lst and boot options.
If you realize that you often need to switch to some other non-default OS (e.g. Windows) having to reboot and wait for the GRUB menu to appear is tedious. GRUB offers a way to record your OS choice when restarting instead of waiting for the menu, by designating a temporary new default which will be reset as soon as it has been used.
The hiddenmenu option can be used in order to hide the menu by default. That way no menu is displayed and the default option is going to be automatically selected after the timeout passes.Still, you are able to press Esc and the menu shows up. To use it, just add to your /boot/grub/menu.lst: 2ff7e9595c
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