diff --git a/en_US.ISO8859-1/books/handbook/boot/chapter.xml b/en_US.ISO8859-1/books/handbook/boot/chapter.xml index 688dd56868..1029d8f5a5 100644 --- a/en_US.ISO8859-1/books/handbook/boot/chapter.xml +++ b/en_US.ISO8859-1/books/handbook/boot/chapter.xml @@ -173,18 +173,13 @@ Master Boot Record (MBR) - The code in the MBR or boot manager is + The boot manager code in the MBR is sometimes referred to as stage zero of the - boot process. This section discusses two boot managers: - boot0 and - LILO. + boot process. By default, &os; uses the + boot0 boot manager. - - The <application>boot0</application> Boot - Manager: - - The MBR installed by &os;'s installer - or &man.boot0cfg.8; is based on + The MBR installed by the &os; installer + is based on /boot/boot0. The size and capability of boot0 is restricted to 446 bytes due to the slice table and 0x55AA @@ -192,7 +187,6 @@ boot0 and multiple operating systems are installed, a message similar to this example will be displayed at boot time: - <filename>boot0</filename> Screenshot @@ -203,7 +197,7 @@ F2 FreeBSD Default: F2 - Other operating systems, in particular &windows;, will + Other operating systems will overwrite an existing MBR if they are installed after &os;. If this happens, or to replace the existing MBR with the &os; @@ -219,65 +213,37 @@ Default: F2 for the first SCSI disk. To create a custom configuration of the MBR, refer to &man.boot0cfg.8;. - - - The LILO Boot Manager: - - To install this boot manager so it will also boot &os;, - boot into Linux and add the following to the existing - /etc/lilo.conf configuration: - - - other=/dev/hdXY -table=/dev/hdX -loader=/boot/chain.b -label=FreeBSD - - Specify &os;'s primary partition and drive using Linux - specifiers, replacing X with the - Linux drive letter and Y with the - Linux primary partition number. For a SCSI - drive, change /dev/hd to - /dev/sd. The - line can be omitted if - both operating systems are installed on the same drive. Next, - run /sbin/lilo -v to commit the new - changes. Verify these are correct by checking the screen - messages. Stage One and Stage Two Conceptually, the first and second stages are part of the - same program, on the same area of the disk. Because of space + same program on the same area of the disk. Because of space constraints, they have been split into two, but are always installed together. They are copied from the combined - /boot/boot by the installer or - &man.bsdlabel.8;. + /boot/boot by the &os; installer or + bsdlabel. - They are located outside file systems, in the first track + These two stages are located outside file systems, in the first track of the boot slice, starting with the first sector. This is - where boot0 (), or any other + where boot0, or any other boot manager, expects to find a program to run which will - continue the boot process. The number of sectors used is - easily determined from the size of - /boot/boot. + continue the boot process. - boot1 is very simple, since it can - only be 512 bytes in size, and knows just enough about the + The first stage, boot1, is very simple, since it can + only be 512 bytes in size. It knows just enough about the &os; bsdlabel, which stores information about the slice, to find and execute boot2. - boot2 is slightly more sophisticated, - and understands the &os; file system enough to find files, and + Stage two, boot2, is slightly more sophisticated, + and understands the &os; file system enough to find files. It can provide a simple interface to choose the kernel or loader - to run. - - However, &man.loader.8; is much more sophisticated and - provides a boot configuration which is run by - boot2. + to run. It runs loader, which is much more sophisticated and + provides a boot configuration file. If the boot process is + interrupted at stage two, the following interactive screen is + displayed: <filename>boot2</filename> Screenshot @@ -287,26 +253,23 @@ Default: 0:ad(0,a)/boot/loader boot: - &man.bsdlabel.8; can be used to replace the installed + To replace the installed boot1 and - boot2: + boot2, use bsdlabel, + where diskslice is the disk and + slice to boot from, such as ad0s1 + for the first slice on the first IDE + disk: &prompt.root; bsdlabel -B diskslice - where diskslice is the disk and - slice to boot from, such as ad0s1 - for the first slice on the first IDE - disk. - - Dangerously Dedicated Mode - If just the disk name is used, such as - ad0, &man.bsdlabel.8; will create a - dangerously dedicated disk, without slices. + ad0, bsdlabel will create the disk in + dangerously dedicated mode, without slices. This is probably not the desired action, so double check the - diskslice passed to - &man.bsdlabel.8; before pressing + diskslice + before pressing Return. @@ -316,16 +279,16 @@ boot: boot-loader - The loader is the final stage of the three-stage - bootstrap, and is located on the file system, usually as + The loader is the final stage of the three-stage + bootstrap process. It is located on the file system, usually as /boot/loader. - The loader is intended as an interactive method for + The loader is intended as an interactive method for configuration, using a built-in command set, backed up by a more powerful interpreter which has a more complex command set. - During initialization, the loader will probe for a + During initialization, loader will probe for a console and for disks, and figure out which disk it is booting from. It will set variables accordingly, and an interpreter is started where user commands can be passed from @@ -334,7 +297,7 @@ boot: loader loader configuration - The loader will then read + The loader will then read /boot/loader.rc, which by default reads in /boot/defaults/loader.conf which sets reasonable defaults for variables and reads @@ -343,166 +306,135 @@ boot: these variables, loading whichever modules and kernel are selected. - Finally, by default, the loader issues a 10 second wait + Finally, by default, loader issues a 10 second wait for key presses, and boots the kernel if it is not interrupted. If interrupted, the user is presented with a prompt which understands the command set, where the user may adjust variables, unload all modules, load modules, and then - finally boot or reboot. + finally boot or reboot. lists the most + commonly used loader commands. For + a complete discussion of all available commands, refer to + &man.loader.8;. - + Loader Built-In Commands - These are the most commonly used loader commands. For a - complete discussion of all available commands, refer to - &man.loader.8;. - - - - autoboot seconds - - - Proceeds to boot the kernel if not interrupted + + + + Variable + Description + + + + + + autoboot seconds + Proceeds to boot the kernel if not interrupted within the time span given, in seconds. It displays a countdown, and the default time span is 10 - seconds. - - + seconds. + - - boot + + boot -options - kernelname - - - Immediately proceeds to boot the kernel, with any + kernelname + Immediately proceeds to boot the kernel, with any specified options or kernel name. Providing a kernel name on the command-line is only applicable after an - unload command has been issued; - otherwise the previously-loaded kernel will be - used. - - + unload has been issued. + Otherwise the previously-loaded kernel will be + used. + - - boot-conf - - - Goes through the same automatic configuration of + + boot-conf + Goes through the same automatic configuration of modules based on specified variables, most commonly kernel. This only makes sense if unload is used first, before - changing some variables. - - + changing some variables. + - - help - topic - - - Shows help messages read from + + help + topic + Shows help messages read from /boot/loader.help. If the topic given is index, the list of - available topics is displayed. - - + available topics is displayed. + - - include filename - … + + include filename + … + Reads the specified file and interprets it line by line. An + error immediately stops the include. + - - Processes the file with the given filename. The - file is read in and interpreted line by line. An - error immediately stops the include command. - - - - - load -t + + load -t type - filename - - - Loads the kernel, kernel module, or file of the + filename + Loads the kernel, kernel module, or file of the type given, with the specified filename. Any arguments after filename - are passed to the file. - - + are passed to the file. + - - ls -l - path - - - Displays a listing of files in the given path, or + + ls -l + path + Displays a listing of files in the given path, or the root directory, if the path is not specified. If is specified, file sizes will - also be shown. - - + also be shown. + - - lsdev - -v - - - Lists all of the devices from which it may be + + lsdev + -v + Lists all of the devices from which it may be possible to load modules. If is - specified, more details are printed. - - + specified, more details are printed. + - - lsmod - -v + + lsmod + -v + Displays loaded modules. If + is specified, more details are shown. + - - Displays loaded modules. If - is specified, more details are shown. - - + + more filename + Displays the files specified, with a pause at each + LINES displayed. + - - more filename + + reboot + Immediately reboots the system. + - - Displays the files specified, with a pause at each - LINES displayed. - - + + set variable, set + variable=value + Sets the specified environment variables. + - - reboot + + unload + Removes all loaded modules. + + + +
+ - - Immediately reboots the system. - - - - - set variable - set - variable=value - - - Sets the loader's environment variables. - - - - - unload - - - Removes all loaded modules. - - - - - - + Loader Examples Here are some practical examples of loader usage: @@ -547,7 +479,6 @@ boot: load -t userconfig_script /boot/kernel.conf -