admin-guide/nfs/nfsroot.rst

10 	Updated 2006 by Nico Schottelius <nico-kernel-nfsroot@schottelius.org>
18 In order to use a diskless system, such as an X-terminal or printer server for
19 example, it is necessary for the root filesystem to be present on a non-disk
21 Documentation/filesystems/ramfs-rootfs-initramfs.rst), a ramdisk (see
22 Documentation/admin-guide/initrd.rst) or a filesystem mounted via NFS. The
34 built-in during configuration. Once this has been selected, the nfsroot
47 When the kernel has been loaded by a boot loader (see below) it needs to be
54   This is necessary to enable the pseudo-NFS-device. Note that it's not a
59 nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]
63   <server-ip>	Specifies the IP address of the NFS server.
68   <root-dir>	Name of the directory on the server to mount as root.
70 		replaced by the ASCII-representation of the client's
73   <nfs-options>	Standard NFS options. All options are separated by commas.
88 ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>:<dns0-ip>:<dns1-ip>:<nt…
91   nfsaddrs, but now the boot-time IP configuration works independently of
106   <client-ip>	IP address of the client.
109   <server-ip>	IP address of the NFS server.
124   <gw-ip>	IP address of a gateway if the server is on a different subnet.
138 		If specified and DHCP is used, the user-provided hostname (and NIS
151   <autoconf>	Method to use for autoconfiguration.
172 		format "ip=dhcp,client-id-type,client-id-value"
176   <dns0-ip>	IP address of primary nameserver.
183   <dns1-ip>	IP address of secondary nameserver.
184 		See <dns0-ip>.
186   <ntp0-ip>	IP address of a Network Time Protocol (NTP) server.
197   - /proc/net/pnp:
199 	#PROTO: <DHCP|BOOTP|RARP|MANUAL>	(depending on configuration method)
200 	domain <dns-domain>			(if autoconfigured, the DNS domain)
201 	nameserver <dns0-ip>			(primary name server IP)
202 	nameserver <dns1-ip>			(secondary name server IP)
203 	nameserver <dns2-ip>			(tertiary name server IP)
204 	bootserver <server-ip>			(NFS server IP)
206   - /proc/net/ipconfig/ntp_servers:
208 	<ntp0-ip>				(NTP server IP)
209 	<ntp1-ip>				(NTP server IP)
210 	<ntp2-ip>				(NTP server IP)
212   <dns-domain> and <dns2-ip> (in /proc/net/pnp) and <ntp1-ip> and <ntp2-ip>
229   log at boot time so that administrators can verify that the correct
242   found in Documentation/driver-api/early-userspace/early_userspace_support.rst
245 Boot Loader
252 - Booting from a floppy using syslinux
254 	When building kernels, an easy way to create a boot floppy that uses
271 		a floppy using dd, configure the boot device using rdev, and
272 		boot using the resulting floppy. Linux no longer supports this
273 		method of booting.
275 - Booting from a cdrom using isolinux
286      	The resulting iso image will be arch/<ARCH>/boot/image.iso
292 	  cdrecord dev=ATAPI:1,0,0 arch/x86/boot/image.iso
297 - Using LILO
312 - Using GRUB
317 - Using loadlin
319 	loadlin may be used to boot Linux from a DOS command prompt without
327 - Using a boot ROM
330 	With a boot ROM the kernel is loaded using the TFTP protocol. The
331 	authors of this document are not aware of any no commercial boot
333 	are two free implementations of a boot ROM, netboot-nfs and
335 	of which contain everything you need to boot a diskless Linux client.
337 - Using pxelinux
339 	Pxelinux may be used to boot linux using the PXE boot loader
343 	"kernel <relative-path-below /tftpboot>". The nfsroot parameters
346 	see Documentation/admin-guide/serial-console.rst for more information.
364   Jens-Uwe Mager <jum@anubis.han.de> for his help.