Completely update the Diskless Operation section.
Submitted by: Jean-Francois Dockes <jean-francois.dockes@wanadoo.fr>
This commit is contained in:
Chern Lee
parent
0b61dde25e
commit
2b432f7183
Notes:
svn2git
2020-12-08 03:00:23 +00:00
svn path=/head/; revision=10926
1 changed files with 460 additions and 226 deletions
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@ -1097,256 +1097,490 @@ Exports list on foobar:
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<sect1info>
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<authorgroup>
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<author>
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<firstname>Martin</firstname>
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<surname>Renters</surname>
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<contrib>Contributed by </contrib>
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<firstname>Jean-François</firstname>
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<surname>Dockès</surname>
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<contrib>Updated by </contrib>
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</author>
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</authorgroup>
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</sect1info>
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<title>Diskless Operation</title>
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<indexterm><primary>diskless workstation</primary></indexterm>
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<para><filename>netboot.com</filename>/<filename>netboot.rom</filename>
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allow you to boot your FreeBSD machine over the network and run FreeBSD
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without having a disk on your client. Under 2.0 it is now possible to
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have local swap. Swapping over NFS is also still supported.</para>
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<para>Supported Ethernet cards include: Western Digital/SMC 8003, 8013,
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8216 and compatibles; NE1000/NE2000 and compatibles (requires
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recompile)</para>
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<para>A FreeBSD machine can boot over the network and operate without a
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local disk, using file systems mounted from an NFS server. No system
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modification is necessary, beyond standard configuration files.
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Such a system is easy to set up because all the necessary elements
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are readily available:</para>
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<itemizedlist>
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<listitem>
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<para>There are at least two possible methods to load the kernel over
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the network:</para>
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<itemizedlist>
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<listitem>
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<para><emphasis>PXE</emphasis>: Intel's Preboot Execution
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Environment system is a form of smart boot ROM built into some
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networking cards or motherboards. See &man.pxeboot.8; for more
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details.</para>
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</listitem>
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<listitem>
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<para><emphasis>The <application>etherboot</application>
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port</emphasis> (<filename>/usr/ports/net/etherboot</filename>)
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produces ROM-able code to boot kernels over the network. The code
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can be either burnt into a boot PROM on a network card, or loaded
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from a local floppy (or hard) disk drive, or from a running
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MS-DOS system. Many network cards are supported.</para>
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</listitem>
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</itemizedlist>
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</listitem>
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<listitem>
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<para>A sample script
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(<filename>/usr/local/share/examples/clone_root</filename>) eases
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the creation and maintenance of the workstation's root filesystem
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on the server. The script will probably require a little
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customization but it will get you started very quickly</para>
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</listitem>
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<listitem>
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<para>Standard system startup files exist in <filename>/etc</filename>
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to detect and support a diskless system startup.</para>
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</listitem>
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<listitem>
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<para>Swapping, if needed, can be done either to an NFS file or to
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a local disk</para>
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</listitem>
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</itemizedlist>
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<para>There are many ways to set up diskless workstations. Many
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elements are involved, and most can be customized to suit local
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taste. The following will describe the setup of a complete system,
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emphasising simplicity and compatibility with the
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standard FreeBSD startup scripts. The system described has the
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following characteristics:</para>
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<itemizedlist>
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<listitem>
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<para>The diskless workstations use a shared
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read-only <filename>root</filename> filesystem, and a shared
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read-only <filename>/usr</filename>.</para>
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<para>The <filename>root</filename> file system is a copy of a
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standard FreeBSD root (typically the server's), with some
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configuration files overriden by ones specific to diskless
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operation or, possibly, to the workstation they belong to.</para>
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<para>The parts of the <filename>root</filename> which have to be
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writable are overlayed with &man.mfs.8; filesystems. Any changes
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will be lost when the system reboots.</para>
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</listitem>
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<listitem>
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<para>The kernel is loaded by <application>etherboot
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</application>, using DHCP (or BOOTP) and TFTP.</para>
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</listitem>
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</itemizedlist>
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<caution><para>As described, this system is insecure. It should
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live in a protected area of a network, and be untrusted by
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other hosts.</para>
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</caution>
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<sect2>
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<title>Setup Instructions</title>
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<procedure>
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<step>
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<para>Find a machine that will be your server. This machine will
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require enough disk space to hold the FreeBSD 2.0 binaries and
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have bootp, tftp and NFS services available. Tested
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machines:</para>
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<itemizedlist>
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<indexterm><primary>HP-UX</primary></indexterm>
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<listitem>
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<para>HP9000/8xx running HP-UX 9.04 or later (pre 9.04 does not
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work)</para>
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</listitem>
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<indexterm><primary>Solaris</primary></indexterm>
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<listitem>
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<para>Sun/Solaris 2.3. (you may need to get bootp)</para>
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</listitem>
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</itemizedlist>
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</step>
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<step>
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<para>Set up a bootp server to provide the client with IP address, gateway,
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netmask.</para>
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<programlisting>diskless:\
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:ht=ether:\
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:ha=0000c01f848a:\
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:sm=255.255.255.0:\
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:hn:\
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:ds=192.1.2.3:\
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:ip=192.1.2.4:\
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:gw=192.1.2.5:\
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:vm=rfc1048:</programlisting>
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</step>
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<sect3>
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<title>Configuring DHCP/BOOTP</title>
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<indexterm><primary>TFTP</primary></indexterm>
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<indexterm><primary>bootp</primary></indexterm>
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<step>
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<para>Set up a TFTP server (on same machine as bootp server) to
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provide booting information to client. The name of this file is
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<filename>cfg.<replaceable>X.X.X.X</replaceable></filename> (or
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<filename>/tftpboot/cfg.<replaceable>X.X.X.X</replaceable></filename>,
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it will try both) where <replaceable>X.X.X.X</replaceable> is the
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IP address of the client. The contents of this file can be any
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valid netboot commands. Under 2.0, netboot has the following
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commands:</para>
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<para>There are two protocols that are commonly used to boot a
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workstation that retrieves its configuration over the network: BOOTP
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and DHCP. They are used at several points in the workstation
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bootstrap:</para>
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<itemizedlist>
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<listitem><para><application>etherboot</application> uses
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DHCP (by default) or BOOTP (needs a configuration option) to
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find the kernel. (PXE uses DHCP).</para>
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</listitem>
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<listitem><para>The kernel uses BOOTP to locate the NFS
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root.</para>
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</listitem>
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</itemizedlist>
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<informaltable frame="none">
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<tgroup cols="2">
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<tbody>
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<row>
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<entry>help</entry>
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<entry>print help list</entry>
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</row>
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<row>
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<entry>ip
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<option><replaceable>X.X.X.X</replaceable></option></entry>
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<entry>print/set client's IP address</entry>
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</row>
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<row>
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<entry>server
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<option><replaceable>X.X.X.X</replaceable></option></entry>
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<entry>print/set bootp/tftp server address</entry>
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</row>
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<row>
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<entry>netmask
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<option><replaceable>X.X.X.X</replaceable></option></entry>
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<entry>print/set netmask</entry>
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</row>
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<para>It is possible to configure a system to use only BOOTP.
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The &man.bootpd.8; server program is included in the
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base FreeBSD system.</para>
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<row>
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<entry>hostname <replaceable>name</replaceable></entry>
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<entry>print/set hostname</entry>
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</row>
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<row>
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<entry>kernel
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<option><replaceable>name</replaceable></option></entry>
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<entry>print/set kernel name</entry>
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</row>
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<row>
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<entry>rootfs
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<option><replaceable>ip:/fs</replaceable></option></entry>
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<entry>print/set root filesystem</entry>
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</row>
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<row>
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<entry>swapfs
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<option><replaceable>ip:/fs</replaceable></option></entry>
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<entry>print/set swap filesystem</entry>
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</row>
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<row>
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<entry>swapsize
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<option><replaceable>size</replaceable></option></entry>
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<entry>set diskless swapsize in KBytes</entry>
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</row>
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<row>
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<entry>diskboot</entry>
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<entry>boot from disk</entry>
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</row>
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<row>
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<entry>autoboot</entry>
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<entry>continue boot process</entry>
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</row>
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<row>
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<entry>trans
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<option>on</option>|<option>off</option></entry>
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<entry>turn transceiver on|off</entry>
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</row>
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<row>
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<entry>flags
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<option>b</option><option>c</option><option>d</option><option>h</option><option>s</option><option>v</option></entry>
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<entry>set boot flags</entry>
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</row>
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</tbody>
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</tgroup>
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</informaltable>
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<para>A typical completely diskless config file might contain:</para>
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<para>However, DHCP has a number of advantages over BOOTP (nicer
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configuration files, possibility of using PXE, plus many others
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not directly related to diskless operation), and we shall describe
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both a pure BOOTP, and a BOOTP+DHCP configuration, with an
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emphasis on the latter, which will use the ISC DHCP software
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package.</para>
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<programlisting>rootfs 192.1.2.3:/rootfs/myclient
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swapfs 192.1.2.3:/swapfs
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swapsize 20000
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hostname myclient.mydomain</programlisting>
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<sect4>
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<title>Configuration using ISC DHCP</title>
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<para>A config file for a machine with local swap might contain:</para>
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<para>The <application>isc-dhcp</application> server can answer
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both BOOTP and DHCP requests.</para>
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<programlisting>rootfs 192.1.2.3:/rootfs/myclient
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hostname myclient.mydomain</programlisting>
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</step>
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<para>As of release 4.4, <application>isc-dhcp</application> is not part of the base
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system. You will first need to install the
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<filename>/usr/ports/net/isc-dhcp3</filename> port or the
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corresponding package. Please refer to <xref linkend="ports">
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for general information about ports and packages.</para>
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<step>
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<para>Ensure that your NFS server has exported the root (and swap if
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applicable) filesystems to your client, and that the client has
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root access to these filesystems A typical
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<filename>/etc/exports</filename> file on FreeBSD might look
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like:</para>
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<programlisting>/rootfs/myclient -maproot=0:0 myclient.mydomain
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/swapfs -maproot=0:0 myclient.mydomain</programlisting>
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<para>Once <application>isc-dhcp</application> is installed, it
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needs a configuration file to run, (normally named
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<filename>/usr/local/etc/dhcpd.conf</filename>). Here follows
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a commented example:</para>
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<para>And on HP-UX:</para>
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<programlisting>
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default-lease-time 600;
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max-lease-time 7200;
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authoritative;
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<programlisting>/rootfs/myclient -root=myclient.mydomain
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/swapfs -root=myclient.mydomain</programlisting>
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</step>
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<indexterm>
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<primary>NFS</primary>
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<secondary>swapping over</secondary>
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</indexterm>
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<step>
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<para>If you are swapping over NFS (completely diskless
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configuration) create a swap file for your client using
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<command>dd</command>. If your <command>swapfs</command>
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command has the arguments <filename>/swapfs</filename> and
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the size 20000 as in the example above, the swapfile for
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<hostid>myclient</hostid> will be called
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<filename>/swapfs/swap.<replaceable>X.X.X.X</replaceable></filename>
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where <replaceable>X.X.X.X</replaceable> is the client's IP
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address, e.g.:</para>
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<screen>&prompt.root; <userinput>dd if=/dev/zero of=/swapfs/swap.192.1.2.4 bs=1k count=20000</userinput></screen>
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<para>Also, the client's swap space might contain sensitive
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information once swapping starts, so make sure to restrict read
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and write access to this file to prevent unauthorized
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access:</para>
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<screen>&prompt.root; <userinput>chmod 0600 /swapfs/swap.192.1.2.4</userinput></screen>
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</step>
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option domain-name "mydom.com";
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option domain-name-servers 192.168.4.1;
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option routers 192.168.4.1;
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<step>
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<para>Unpack the root filesystem in the directory the client will
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use for its root filesystem (<filename>/rootfs/myclient</filename>
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in the example above).</para>
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<itemizedlist>
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<listitem>
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<para>On HP-UX systems: The server should be running HP-UX 9.04
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or later for HP9000/800 series machines. Prior versions do not
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allow the creation of device files over NFS.</para>
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</listitem>
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subnet 192.168.4.0 netmask 255.255.255.0 {
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use-host-decl-names on; <co id="co-dhcp-host-name">
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option subnet-mask 255.255.255.0;
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option broadcast-address 192.168.4.255;
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host margaux {
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hardware ethernet 01:23:45:67:89:ab;
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fixed-address margaux.mydom.com;
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next-server 192.168.4.4;<co id="co-dhcp-next-server">
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filename "/tftpboot/kernel.diskless";<co id="co-dhcp-filename">
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option root-path "192.168.4.4:/data/misc/diskless";<co id="co-dhcp-root-path">
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}
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}
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</programlisting>
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<calloutlist>
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<callout arearefs="co-dhcp-host-name"><para>This option tells
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<command>dhcpd</command> to send the value in the
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<literal>host</literal> declarations as the hostname for the
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diskless host. An alternate way would be to add an
|
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<literal>option host-name
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<replaceable>margaux</replaceable></literal> inside the
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host declarations.</para>
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</callout>
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<listitem>
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<para>When extracting <filename>/dev</filename> in
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<filename>/rootfs/myclient</filename>, beware that some
|
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systems (HPUX) will not create device files that FreeBSD is
|
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happy with. You may have to go to single user mode on the
|
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first bootup (press control-c during the bootup phase), cd
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<filename>/dev</filename> and do a <command>sh ./MAKEDEV
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all</command> from the client to fix this.</para>
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</listitem>
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</itemizedlist>
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</step>
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<callout arearefs="co-dhcp-next-server"><para>The
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<literal>next-server</literal> directive designates
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the TFTP server (the default is to use the same host as the
|
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DHCP server).</para>
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</callout>
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|
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<callout arearefs="co-dhcp-filename"><para>The
|
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<literal>filename</literal> directive defines the file that
|
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<application>etherboot</application> will load as a
|
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kernel.
|
||||
<note><para>PXE appears to prefer a relative file
|
||||
name, and it loads <command>pxeboot</command>, not the
|
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kernel (<literal>option filename
|
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"pxeboot"</literal>).</para>
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</note>
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</para>
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</callout>
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|
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<callout arearefs="co-dhcp-root-path"><para>The
|
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<literal>root-path</literal> option defines the path to
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the root filesystem, in usual NFS notation</para>
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</callout>
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||||
</calloutlist>
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<step>
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<para>Run <command>netboot.com</command> on the client or make an
|
||||
EPROM from the <filename>netboot.rom</filename> file</para>
|
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</step>
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||||
</procedure>
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</sect2>
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<sect2>
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<title>Using Shared <filename>/</filename> and <filename>/usr</filename>
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Filesystems</title>
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</sect4>
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<sect4>
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<title>Configuration using BOOTP</title>
|
||||
|
||||
<para>Here follows an equivalent <command>bootpd</command>
|
||||
configuration. This would be found in
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||||
<filename>/etc/bootptab</filename>.</para>
|
||||
|
||||
<para>Please note that <application>etherboot</application> must
|
||||
be compiled with the non-default option
|
||||
<literal>NO_DHCP_SUPPORT</literal> in order to use BOOTP, and that PXE
|
||||
<emphasis>needs</emphasis> DHCP. The only obvious advantage of
|
||||
<application>bootpd</application> is that it exists in the base system.</para>
|
||||
|
||||
<programlisting>
|
||||
.def100:\
|
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:hn:ht=1:sa=192.168.4.4:vm=rfc1048:\
|
||||
:sm=255.255.255.0:\
|
||||
:ds=192.168.4.1:\
|
||||
:gw=192.168.4.1:\
|
||||
:hd="/tftpboot":\
|
||||
:bf="/kernel.diskless":\
|
||||
:rp="192.168.4.4:/data/misc/diskless":
|
||||
|
||||
margaux:ha=0123456789ab:tc=.def100
|
||||
</programlisting>
|
||||
</sect4>
|
||||
</sect3>
|
||||
|
||||
<sect3>
|
||||
<title>Preparing a boot program with
|
||||
<application>Etherboot</application></title>
|
||||
|
||||
<para><ulink url="http://etherboot.sourceforge.net">Etherboot's Web
|
||||
site</ulink> contains
|
||||
<ulink url="http://etherboot.sourceforge.net/doc/html/userman.html">
|
||||
extensive documentation</ulink> mainly intended for Linux
|
||||
systems, but nonetheless containing useful information. The following
|
||||
will just outline how you would use
|
||||
<application>etherboot</application> on a FreeBSD system.</para>
|
||||
|
||||
<para>You must first install - and possibly compile - the
|
||||
<application>etherboot</application> package. The
|
||||
<application>etherboot</application> port can normally be found in
|
||||
<filename>/usr/ports/net/etherboot</filename>. If the ports tree is
|
||||
installed on your system, just typing <literal>make</literal> in
|
||||
this directory should take care of everything. Else refer to
|
||||
<xref linkend="ports"> for information about ports and
|
||||
packages.</para>
|
||||
|
||||
<para>For our setup, we shall use a boot floppy. For other methods
|
||||
(PROM, or dos program), please refer to the
|
||||
<application>etherboot</application> documentation.</para>
|
||||
|
||||
<para>To make a boot floppy, insert a floppy in the drive on the
|
||||
machine where you installed <application>etherboot</application>,
|
||||
then change your current directory to the <filename>src</filename>
|
||||
directory in the <application>etherboot</application> tree and
|
||||
type:</para>
|
||||
|
||||
<screen>
|
||||
&prompt.root; <userinput>gmake bin32/<replaceable>devicetype</replaceable>.fd0</userinput>
|
||||
</screen>
|
||||
|
||||
<para><replaceable>devicetype</replaceable> depends on the type of
|
||||
the ethernet card in the diskless workstation. Refer to the
|
||||
<filename>NIC</filename> file in the same directory to determine the
|
||||
right <replaceable>devicetype</replaceable>.</para>
|
||||
|
||||
</sect3>
|
||||
|
||||
|
||||
<sect3>
|
||||
<title>Configuring the TFTP and NFS servers</title>
|
||||
|
||||
<para>You need to enable <command>tftpd</command> on the TFTP
|
||||
server:</para>
|
||||
<procedure>
|
||||
<step>
|
||||
<para>Create a directory from which <command>tftpd</command>
|
||||
will serve the files, ie: <filename>/tftpboot</filename></para>
|
||||
</step>
|
||||
|
||||
<step>
|
||||
<para>Add this line to your
|
||||
<filename>/etc/inetd.conf</filename>:</para>
|
||||
|
||||
<programlisting>tftp dgram udp wait nobody /usr/libexec/tftpd tftpd /tftpboot</programlisting>
|
||||
|
||||
<note><para>It appears that at least some PXE versions wants
|
||||
the TCP version of TFTP. In this case, add a second line,
|
||||
replacing <literal>dgram udp</literal> with <literal>stream
|
||||
tcp</literal></para>
|
||||
</note>
|
||||
</step>
|
||||
<step>
|
||||
<para>Tell <command>inetd</command> to reread its configuration
|
||||
file:</para>
|
||||
<screen>&prompt.root; <userinput>kill -HUP `cat /var/run/inetd.pid`</userinput></screen>
|
||||
</step>
|
||||
</procedure>
|
||||
|
||||
<para>You can place the tftpboot directory anywhere on the server, but,
|
||||
of course, the actual location, the value in
|
||||
<filename>inetd.conf</filename>, and the value in
|
||||
<filename>dhcpd.conf</filename> must be consistent !</para>
|
||||
|
||||
<para>You also need to enable NFS service and export the
|
||||
appropriate filesystem on the NFS server</para>
|
||||
|
||||
<procedure>
|
||||
<step>
|
||||
<para>Add this to <filename>/etc/rc.conf</filename>:</para>
|
||||
<programlisting>nfs_server_enable="YES"</programlisting>
|
||||
</step>
|
||||
|
||||
<step>
|
||||
<para>Export the filesystem where the diskless root directory
|
||||
is located by adding the following to
|
||||
<filename>/etc/exports</filename> (adjust the volume mount
|
||||
point and workstation name!):</para>
|
||||
<programlisting><replaceable>/data/misc</replaceable> -alldirs -ro <replaceable>margaux</replaceable></programlisting>
|
||||
</step>
|
||||
<step>
|
||||
<para>Tell <command>mountd</command> to reread its configuration
|
||||
file. If you actually needed to configure NFS service at step
|
||||
1, you probably want to reboot instead.</para>
|
||||
<screen>&prompt.root; <userinput>kill -HUP `cat /var/run/mountd.pid`</userinput></screen>
|
||||
</step>
|
||||
</procedure>
|
||||
|
||||
</sect3>
|
||||
|
||||
<sect3>
|
||||
<title>Building a diskless kernel</title>
|
||||
|
||||
<para>Create a kernel configuration file for the diskless client
|
||||
with the following options (in addition to the usual
|
||||
ones):</para>
|
||||
|
||||
<programlisting>
|
||||
options BOOTP # Use BOOTP to obtain IP address/hostname
|
||||
options BOOTP_NFSROOT # NFS mount root filesystem using BOOTP info
|
||||
options BOOTP_COMPAT # Workaround for broken bootp daemons.
|
||||
</programlisting>
|
||||
|
||||
<para>You may also want to use <literal>BOOTP_NFSV3</literal> and
|
||||
<literal>BOOTP_WIRED_TO</literal> (refer to <filename>LINT</filename>).</para>
|
||||
|
||||
<para>Build the kernel (See <xref linkend="kernelconfig">),
|
||||
and copy it to the tftp directory, under the name listed
|
||||
in <filename>dhcpd.conf</filename></para>
|
||||
|
||||
|
||||
</sect3>
|
||||
|
||||
<sect3>
|
||||
<title>Preparing the root filesystem</title>
|
||||
|
||||
<para>You need to create a root filesystem for the diskless
|
||||
workstations, in the location listed as
|
||||
<literal>root-path</literal> in
|
||||
<filename>dhcpd.conf</filename>.</para>
|
||||
|
||||
<para>The easiest way to do this is to use the
|
||||
<filename>/usr/share/examples/diskless/clone_root</filename>
|
||||
shell script. This script needs customization, at least to adjust the
|
||||
place where the filesystem will be created (the
|
||||
<literal>DEST</literal> variable).
|
||||
|
||||
<para>Refer to the comments at the top of the script for
|
||||
instructions. They explain how the base filesystem is built,
|
||||
and how files may be selectively overriden by versions specific
|
||||
to diskless operation, to a subnetwork, or to an individual
|
||||
workstation. They also give examples for the diskless
|
||||
<filename>/etc/fstab</filename> and <filename>
|
||||
/etc/rc.conf</filename></para>
|
||||
|
||||
<para>The README files in
|
||||
<filename>/usr/share/examples/diskless</filename> contain a lot
|
||||
of interesting background information, but, together with the
|
||||
other examples in the <filename>diskless</filename> directory,
|
||||
they actually document a configuration method which is distinct
|
||||
from the one used by <filename>clone_root</filename> and
|
||||
<filename>/etc/rc.diskless[12]</filename>, which is a little
|
||||
confusing. Use them for reference only, except if you prefer
|
||||
the method that they describe, in which case you will need
|
||||
customized <filename>rc</filename> scripts</para>
|
||||
|
||||
<para>As of FreeBSD version 4.4-RELEASE, there is a small
|
||||
incompatibility between the <filename>clone_root</filename>
|
||||
script and the <filename>/etc/rc.diskless1</filename>
|
||||
script. Please refer to PR
|
||||
<ulink url="http://www.freebsd.org/cgi/query-pr.cgi?pr=31200">
|
||||
conf/31200</ulink> for the small adjustment needed in
|
||||
<filename>clone_root</filename>.
|
||||
Also see PR
|
||||
<ulink url="http://www.freebsd.org/cgi/query-pr.cgi?pr=29870">conf/29870</ulink>
|
||||
about a small adjustment needed in
|
||||
<filename>/etc/rc.diskless2</filename>.
|
||||
</para>
|
||||
</sect3>
|
||||
|
||||
<sect3>
|
||||
<title>Configuring swap</title>
|
||||
|
||||
<para>If needed, it is possible to do swapping over NFS, to a file
|
||||
on the server. The exact <filename>bootptab</filename> or
|
||||
<filename>dhcpd.conf</filename> options are a little mysterious
|
||||
and poorly documented. Anyway, here is what worked for me, using
|
||||
isc-dhcp 3.0rc11.</para>
|
||||
<procedure>
|
||||
<step><para>Add the following lines to
|
||||
<filename>dhcpd.conf</filename>:</para>
|
||||
<programlisting>
|
||||
# Global section
|
||||
option swap-path code 128 = string;
|
||||
option swap-size code 129 = integer 32;
|
||||
|
||||
host margaux {
|
||||
... # Standard lines, see above
|
||||
option swap-path <replaceable>"192.168.4.4:/netswapvolume/netswap"</replaceable>;
|
||||
option swap-size <replaceable>64000</replaceable>;
|
||||
}
|
||||
</programlisting>
|
||||
<para>The idea is that, at least for a FreeBSD client,
|
||||
DHCP/BOOTP option code 128 is the path to the NFS swap file,
|
||||
and option code 129 is the swap size in kilobytes. Older
|
||||
versions of <command>dhcpd</command> allowed a syntax of
|
||||
<literal>option option-128 "...</literal>, which does not
|
||||
seem to work any more.</para>
|
||||
<para><filename>/etc/bootptab</filename> would use the
|
||||
following syntax instead:
|
||||
<literal>T128="192.168.4.4:/netswapvolume/netswap":T129=64000
|
||||
</literal></para>
|
||||
</step>
|
||||
|
||||
<step>
|
||||
<para>On the NFS swap file server, create the swap
|
||||
file(s)</para>
|
||||
<screen>
|
||||
&prompt.root; <userinput>mkdir <replaceable>/netswapvolume/netswap</replaceable></userinput>
|
||||
&prompt.root; <userinput>cd <replaceable>/netswapvolume/netswap</replaceable></userinput>
|
||||
&prompt.root; <userinput>dd if=/dev/zero bs=1024 count=<replaceable>64000</replaceable> of=swap.<replaceable>192.168.4.6</replaceable></userinput>
|
||||
&prompt.root; <userinput>chmod 0600 swap.<replaceable>192.168.4.6</replaceable></userinput>
|
||||
</screen>
|
||||
<para><replaceable>192.168.4.6</replaceable> is the IP address
|
||||
for the diskless client</para>
|
||||
</step>
|
||||
|
||||
<step>
|
||||
<para>On the NFS swap file server, add the following line to
|
||||
<filename>/etc/exports</filename></para>
|
||||
<programlisting>
|
||||
<replaceable>/netswapvolume</replaceable> -maproot=0:10 -alldirs <replaceable>margaux</replaceable>
|
||||
</programlisting>
|
||||
<para>Then tell mountd to reread the exports file, as above.</para>
|
||||
</step>
|
||||
</procedure>
|
||||
|
||||
</sect3>
|
||||
|
||||
<sect3>
|
||||
<title>Miscellaneous issues</title>
|
||||
|
||||
|
||||
<sect4>
|
||||
<title>Running with a read-only <filename>/usr</filename></title
|
||||
<para>If the diskless workstation is configured to run X, you
|
||||
will have to adjust the xdm configuration file, which puts
|
||||
the error log on <filename>/usr</filename> by default.</para>
|
||||
</sect4>
|
||||
<sect4>
|
||||
<title>Using a non-FreeBSD server</title>
|
||||
|
||||
<para>When the server for the root filesystem is not running FreeBSD,
|
||||
you will have to create the root file system on a
|
||||
FreeBSD machine, then copy it to its destination, using
|
||||
<command>tar</command> or <command>cpio</command>.</para>
|
||||
<para>In this situation, it seems that there are sometimes
|
||||
problems with the special files in <filename>/dev</filename>,
|
||||
because of differing minor/major number integer sizes. It seems
|
||||
that a solution to this problem is to run MAKEDEV on a FreeBSD
|
||||
machine, in a directory mounted through NFS from the final
|
||||
server.</para>
|
||||
|
||||
</sect4>
|
||||
|
||||
</sect3>
|
||||
|
||||
<para>Although this is not an officially sanctioned or supported way
|
||||
of doing this, some people report that it works quite well. If
|
||||
anyone has any suggestions on how to do this cleanly, please tell
|
||||
&a.doc;.</para>
|
||||
</sect2>
|
||||
|
||||
<sect2>
|
||||
<title>Compiling Netboot for Specific Setups</title>
|
||||
|
||||
<para>Netboot can be compiled to support NE1000/2000 cards by changing
|
||||
the configuration in
|
||||
<filename>/sys/i386/boot/netboot/Makefile</filename>. See the
|
||||
comments at the top of this file.</para>
|
||||
</sect2>
|
||||
</sect1>
|
||||
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue