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diff --git a/share/doc/handbook/booting.sgml b/share/doc/handbook/booting.sgml deleted file mode 100644 index ff34296..0000000 --- a/share/doc/handbook/booting.sgml +++ /dev/null @@ -1,173 +0,0 @@ -<!-- This is a SGML version of the text on FreeBSD boot procedures - made by Poul-Henning Kamp <phk@FreeBSD.ORG> - - This conversion has been made by Ollivier Robert. - - $Id$ - - -<!DOCTYPE linuxdoc PUBLIC "-//FreeBSD//DTD linuxdoc//EN"> - - <article> - - <title>Boot overview</title> - <author>Poul-Henning Kamp, <tt/<phk@login.dknet.dk>/</author> - <date>v1.1, April 26th</date> - <abstract> - Booting FreeBSD is essentially a three step: Load the kernel, - determine the root filesystem and initialize user-land things. This - leads to some interesting possibilities as shown below... - </abstract> - - <toc> ---> - - <sect><heading>The FreeBSD Booting Process<label id="booting"></heading> - - <p><em>Contributed by &a.phk;. v1.1, April 26th.</em> - - Booting FreeBSD is essentially a three step: Load the kernel, - determine the root filesystem and initialize user-land things. This - leads to some interesting possibilities shown below. - - <sect1><heading>Loading a kernel</heading> - <p> - We presently have three basic mechanisms for loading the - kernel as described below: - They all pass some - information to the kernel to help the kernel decide what to do - next. - - <descrip> - <tag>Biosboot</tag> - - Biosboot is our ``bootblocks'', it consists of two files, which - will be installed in the first 8Kbytes of the floppy or hard-disk - slice to be booted from. - - Biosboot can load a kernel from a FreeBSD filesystem. - - <tag>Dosboot</tag> - - Dosboot was written by DI. Christian Gusenbauer, and is - unfortunately at this time one of the few pieces of code that - will not compile under FreeBSD itself because it is written for - Microsoft compilers. - - Dosboot will boot the kernel from a MS-DOS file or from a FreeBSD - filesystem partition on the disk. It attempts to negotiate with - the various and strange kinds of memory manglers that lurk in - high memory on MS/DOS systems and usually wins them for its - case. - - <tag>Netboot</tag> - - Netboot will try to find a supported Ethernet card, and use - BOOTP, TFTP and NFS to find a kernel file to boot. -</descrip> - - - <sect1><heading>Determine the root filesystem</heading> - <p> - Once the kernel is loaded and the boot-code jumps to it, the kernel - will initialize itself, trying to determine what hardware is - present and so on, and then it needs to find a root filesystem. - - Presently we support the following types of root filesystems: - -<descrip> - <tag>UFS</tag> - - This is the most normal type of root filesystem. It can reside on - a floppy or on hard disk. - - <tag>MSDOS</tag> - - While this is technically possible, it is not particular useful, - because of ``FAT'' filesystems inability to make links, device - nodes and such ``UNIXisms''. - - <tag>MFS</tag> - - This is actually a UFS filesystem which has been compiled into - the kernel. That means that the kernel does not really need any - disks/floppies or other HW to function. - - <tag>CD9660</tag> - - This is for using a CD-ROM as root filesystem. - - <tag>NFS</tag> - - This is for using a fileserver as root filesystem, basically - making it a diskless machine. -</descrip> - - - <sect1><heading>Initialize user-land things</heading> - <p> - To get the user-land going, when the kernel has finished - initialization, it will create a process with ``<tt/pid == 1/'' and execute - a program on the root filesystem, this program is normally - ``<tt>/sbin/init</tt>''. - - You can substitute any program for /sbin/init, as long as you keep - in mind that: - - there is no stdin/out/err unless you open it yourself, if you exit, - the machine panics, signal handling is special for ``<tt/pid == - 1/''. - - An example of this is the ``<tt>/stand/sysinstall</tt>'' - program on the installation floppy. - - - <sect1><heading>Interesting combinations</heading> - <p> - Boot a kernel with a MFS in it with a special <tt>/sbin/init</tt> - which... - <descrip> - <tag/A -- Using DOS/ - <itemize> - <item>mounts your <tt/C:/ as <tt>/C:</tt> - <item>Attaches <tt>C:/freebsd.fs</tt> on <tt>/dev/vn0</tt> - <item>mounts <tt>/dev/vn0</tt> as <tt>/rootfs</tt> - <item>makes symlinks<newline> - <tt>/rootfs/bin -> /bin</tt><newline> - <tt>/rootfs/etc -> /etc</tt><newline> - <tt>/rootfs/sbin -> /sbin</tt><newline> - (etc...)<newline> - </itemize> - - Now you run FreeBSD without repartitioning your hard disk... - - <tag/B -- Using NFS/ - - NFS mounts your <tt>server:˜you/FreeBSD</tt> as - <tt>/nfs</tt>, chroots to <tt>/nfs</tt> and executes - <tt>/sbin/init</tt> there - - Now you run FreeBSD diskless, even though you do not control - the NFS server... - - <tag/C -- Start an X-server/ - - Now you have an X-terminal, which is better than that dingy - X-under-windows-so-slow-you-can-see-what-it-does thing that - your boss insist is better than forking our money on HW. - - <tag/D -- Using a tape/ - Takes a copy of <tt>/dev/rwd0</tt> and writes it to a remote tape - station or fileserver. - - Now you finally got that backup you should have made a year - ago... - - <tag>E -- Acts as a firewall/web-server/what do I know...</tag> - - This is particular interesting since you can boot from a write- - protected floppy, but still write to your root filesystem... - </descrip> - - - |
