Suppress some ugly memories in the Storage chapter:
* Remove "RAID" section that only covers ccd(4) and ataraid(4). These may still work, but there are better solutions for new users. * Remove Backups to Floppies section. * Add SATA drive names. * Change CDROM to CD-ROM to match the FDP Primer word list. About ccd(4): Once new and useful, thrice ousted from its niche, time's arrow evicts ccd from the Handbook, to live forever in the archives.
This commit is contained in:
Warren Block
parent
1881f39c04
commit
5793bcfc27
Notes:
svn2git
2020-12-08 03:00:23 +00:00
svn path=/head/; revision=42018
1 changed files with 37 additions and 487 deletions
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@ -51,19 +51,11 @@
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<para>How to create and burn CDs and DVDs on &os;.</para>
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</listitem>
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<listitem>
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<para>The various storage media options for backups.</para>
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</listitem>
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<listitem>
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<para>How to use the backup programs available under
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&os;.</para>
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</listitem>
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<listitem>
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<para>How to backup to floppy disks.</para>
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</listitem>
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<listitem>
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<para>What file system snapshots are and how to use them
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efficiently.</para>
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@ -84,7 +76,7 @@
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<title>Device Names</title>
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<para>The following is a list of physical storage devices
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supported in &os;, and their associated device names.</para>
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supported in &os; and their associated device names.</para>
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<table id="disk-naming-physical-table" frame="none">
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<title>Physical Disk Naming Conventions</title>
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@ -100,14 +92,27 @@
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<tbody>
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<row>
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<entry>IDE hard drives</entry>
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<entry><literal>ad</literal></entry>
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<entry><literal>ad</literal> or
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<literal>ada</literal></entry>
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</row>
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<row>
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<entry>IDE CDROM drives</entry>
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<entry><literal>acd</literal></entry>
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<entry>IDE CD-ROM drives</entry>
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<entry><literal>acd</literal> or
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<literal>cd</literal></entry>
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</row>
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<row>
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<entry>SATA hard drives</entry>
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<entry><literal>ad</literal> or
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<literal>ada</literal></entry>
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</row>
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<row>
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<entry>SATA CD-ROM drives</entry>
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<entry><literal>acd</literal> or
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<literal>cd</literal></entry>
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</row>
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<row>
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<entry>SCSI hard drives and USB Mass storage
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devices</entry>
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@ -115,12 +120,12 @@
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</row>
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<row>
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<entry>SCSI CDROM drives</entry>
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<entry>SCSI CD-ROM drives</entry>
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<entry><literal>cd</literal></entry>
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</row>
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<row>
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<entry>Assorted non-standard CDROM drives</entry>
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<entry>Assorted non-standard CD-ROM drives</entry>
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<entry><literal>mcd</literal> for Mitsumi CD-ROM and
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<literal>scd</literal> for Sony CD-ROM devices</entry>
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</row>
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@ -242,362 +247,6 @@
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<screen>&prompt.root; <userinput>mount /newdisk</userinput></screen>
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</sect1>
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<sect1 id="raid">
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<title>RAID</title>
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<sect2 id="raid-soft">
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<title>Software RAID</title>
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<sect3 id="ccd">
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<sect3info>
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<authorgroup>
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<author>
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<firstname>Christopher</firstname>
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<surname>Shumway</surname>
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<contrib>Original work by </contrib>
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</author>
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</authorgroup>
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<authorgroup>
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<author>
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<firstname>Jim</firstname>
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<surname>Brown</surname>
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<contrib>Revised by </contrib>
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</author>
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</authorgroup>
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</sect3info>
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<title>Concatenated Disk Driver (CCD) Configuration</title>
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<indexterm><primary>RAID</primary><secondary>software</secondary></indexterm>
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<indexterm><primary>RAID</primary><secondary>CCD</secondary></indexterm>
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<para>When choosing a mass storage solution, the most
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important factors to consider are speed, reliability, and
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cost. It is rare to have all three in balance. Normally a
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fast, reliable mass storage device is expensive, and to cut
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back on cost either speed or reliability must be
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sacrificed.</para>
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<para>In designing the system described below, cost was
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chosen as the most important factor, followed by speed,
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then reliability. Data transfer speed for this system is
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ultimately constrained by the network. While reliability is
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very important, the CCD drive described below serves online
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data that is already fully backed up and which can easily be
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replaced.</para>
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<para>Defining the requirements is the first step in choosing
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a mass storage solution. If the requirements prefer speed
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or reliability over cost, the solution will differ from the
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system described in this section.</para>
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<sect4 id="ccd-installhw">
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<title>Installing the Hardware</title>
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<para>In addition to the IDE system disk, three Western
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Digital 30GB, 5400 RPM IDE disks form the core of the CCD
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disk described below, providing approximately 90GB of
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online storage. Ideally, each IDE disk would have its own
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IDE controller and cable, but to minimize cost, additional
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IDE controllers were not used. Instead, the disks were
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configured with jumpers so that each IDE controller has
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one master, and one slave.</para>
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<para>Upon reboot, the system BIOS was configured to
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automatically detect the disks attached. More
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importantly, &os; detected them on reboot:</para>
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<programlisting>ad0: 19574MB <WDC WD205BA> [39770/16/63] at ata0-master UDMA33
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ad1: 29333MB <WDC WD307AA> [59598/16/63] at ata0-slave UDMA33
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ad2: 29333MB <WDC WD307AA> [59598/16/63] at ata1-master UDMA33
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ad3: 29333MB <WDC WD307AA> [59598/16/63] at ata1-slave UDMA33</programlisting>
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<note><para>If &os; does not detect all the disks, consult
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the drive documentation for proper setup and verify
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that the controller is supported by &os;.</para></note>
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</sect4>
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<sect4 id="ccd-setup">
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<title>Setting Up the CCD</title>
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<para>The &man.ccd.4; driver takes several identical disks
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and concatenates them into one logical file system. In
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order to use &man.ccd.4;, its kernel module must be
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loaded using &man.ccd.4;. When using a custom kernel,
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ensure that this line is compiled in:</para>
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<programlisting>device ccd</programlisting>
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<para>Before configuring &man.ccd.4;, use &man.bsdlabel.8;
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to label the disks:</para>
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<programlisting>bsdlabel -w ad1 auto
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bsdlabel -w ad2 auto
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bsdlabel -w ad3 auto</programlisting>
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<para>This example creates a bsdlabel for
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<devicename>ad1c</devicename>,
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<devicename>ad2c</devicename> and
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<devicename>ad3c</devicename> that spans the entire
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disk.</para>
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<para>The next step is to change the disk label type. Use
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&man.bsdlabel.8; to edit the disks:</para>
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<programlisting>bsdlabel -e ad1
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bsdlabel -e ad2
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bsdlabel -e ad3</programlisting>
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<para>This opens up the current disk label on each disk with
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the editor specified by the <envar>EDITOR</envar>
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environment variable, typically &man.vi.1;.</para>
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<para>An unmodified disk label will look something like
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this:</para>
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<programlisting>8 partitions:
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# size offset fstype [fsize bsize bps/cpg]
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c: 60074784 0 unused 0 0 0 # (Cyl. 0 - 59597)</programlisting>
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<para>Add a new <literal>e</literal> partition for
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&man.ccd.4; to use. This can usually be copied from the
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<literal>c</literal> partition, but the
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<option>fstype</option> <emphasis>must</emphasis> be
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<userinput>4.2BSD</userinput>. The disk label should now
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look something like this:</para>
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<programlisting>8 partitions:
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# size offset fstype [fsize bsize bps/cpg]
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c: 60074784 0 unused 0 0 0 # (Cyl. 0 - 59597)
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e: 60074784 0 4.2BSD 0 0 0 # (Cyl. 0 - 59597)</programlisting>
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</sect4>
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<sect4 id="ccd-buildingfs">
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<title>Building the File System</title>
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<para>Now that all the disks are labeled, build the
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&man.ccd.4; using &man.ccdconfig.8;, with options similar
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to the following:</para>
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<programlisting>ccdconfig ccd0<co id="co-ccd-dev"/> 32<co id="co-ccd-interleave"/> 0<co id="co-ccd-flags"/> /dev/ad1e<co id="co-ccd-devs"/> /dev/ad2e /dev/ad3e</programlisting>
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||||
<para>The use and meaning of each option is described
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below:</para>
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|
||||
<calloutlist>
|
||||
<callout arearefs="co-ccd-dev">
|
||||
<para>The first argument is the device to configure, in
|
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this case, <filename>/dev/ccd0c</filename>. The
|
||||
<literal>/dev/</literal> portion is optional.</para>
|
||||
</callout>
|
||||
|
||||
<callout arearefs="co-ccd-interleave">
|
||||
<para>The interleave for the file system, which defines
|
||||
the size of a stripe in disk blocks, each normally 512
|
||||
bytes. So, an interleave of 32 would be 16,384
|
||||
bytes.</para>
|
||||
</callout>
|
||||
|
||||
<callout arearefs="co-ccd-flags">
|
||||
<para>Flags for &man.ccdconfig.8;. For example, to
|
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enable drive mirroring, specify a flag. This
|
||||
configuration does not provide mirroring for
|
||||
&man.ccd.4;, so it is set at 0 (zero).</para>
|
||||
</callout>
|
||||
|
||||
<callout arearefs="co-ccd-devs">
|
||||
<para>The final arguments to &man.ccdconfig.8; are the
|
||||
devices to place into the array. Use the complete
|
||||
path name for each device.</para>
|
||||
</callout>
|
||||
</calloutlist>
|
||||
|
||||
<para>After running &man.ccdconfig.8; the &man.ccd.4; is
|
||||
configured and a file system can be installed. Refer to
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&man.newfs.8; for options, or run: </para>
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||||
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<programlisting>newfs /dev/ccd0c</programlisting>
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||||
</sect4>
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<sect4 id="ccd-auto">
|
||||
<title>Making it All Automatic</title>
|
||||
|
||||
<para>Generally, &man.ccd.4; should be configured to
|
||||
automount upon each reboot. To do this, write out the
|
||||
current configuration to
|
||||
<filename>/etc/ccd.conf</filename> using the following
|
||||
command:</para>
|
||||
|
||||
<programlisting>ccdconfig -g > /etc/ccd.conf</programlisting>
|
||||
|
||||
<para>During reboot, the script <command>/etc/rc</command>
|
||||
runs <command>ccdconfig -C</command> if
|
||||
<filename>/etc/ccd.conf</filename> exists. This
|
||||
automatically configures the &man.ccd.4; so it can be
|
||||
mounted.</para>
|
||||
|
||||
<note>
|
||||
<para>When booting into single user mode, the following
|
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command must be issued to configure the array before
|
||||
the &man.ccd.4; can be mounted:</para>
|
||||
|
||||
<programlisting>ccdconfig -C</programlisting>
|
||||
</note>
|
||||
|
||||
<para>To automatically mount the &man.ccd.4;, place an entry
|
||||
for the &man.ccd.4; in <filename>/etc/fstab</filename> so
|
||||
it will be mounted at boot time:</para>
|
||||
|
||||
<programlisting>/dev/ccd0c /media ufs rw 2 2</programlisting>
|
||||
</sect4>
|
||||
</sect3>
|
||||
|
||||
<sect3 id="vinum">
|
||||
<title>The Vinum Volume Manager</title>
|
||||
|
||||
<indexterm>
|
||||
<primary>RAID</primary>
|
||||
<secondary>software</secondary>
|
||||
</indexterm>
|
||||
<indexterm>
|
||||
<primary>RAID</primary>
|
||||
<secondary>Vinum</secondary>
|
||||
</indexterm>
|
||||
|
||||
<para>The Vinum Volume Manager is a block device driver which
|
||||
implements virtual disk drives. It isolates disk hardware
|
||||
from the block device interface and maps data in ways which
|
||||
result in an increase in flexibility, performance and
|
||||
reliability compared to the traditional slice view of disk
|
||||
storage. &man.vinum.4; implements the RAID-0, RAID-1 and
|
||||
RAID-5 models, both individually and in combination.</para>
|
||||
|
||||
<para>Refer to <xref linkend="vinum-vinum"/> for more
|
||||
information about &man.vinum.4;.</para>
|
||||
</sect3>
|
||||
</sect2>
|
||||
|
||||
<sect2 id="raid-hard">
|
||||
<title>Hardware RAID</title>
|
||||
|
||||
<indexterm>
|
||||
<primary>RAID</primary>
|
||||
<secondary>hardware</secondary>
|
||||
</indexterm>
|
||||
|
||||
<para>&os; also supports a variety of hardware
|
||||
<acronym>RAID</acronym> controllers. These devices control a
|
||||
<acronym>RAID</acronym> subsystem without the need for &os;
|
||||
specific software to manage the array.</para>
|
||||
|
||||
<para>Using an on-card <acronym>BIOS</acronym>, the card
|
||||
controls most of the disk operations. The following is a
|
||||
brief setup description using a Promise
|
||||
<acronym>IDE</acronym> <acronym>RAID</acronym> controller.
|
||||
When this card is installed and the system is started up, it
|
||||
displays a prompt requesting information. Follow the
|
||||
instructions to enter the card's setup screen and to combine
|
||||
all the attached drives. After doing so, the disks will
|
||||
look like a single drive to &os;. Other
|
||||
<acronym>RAID</acronym> levels can be set up
|
||||
accordingly.</para>
|
||||
</sect2>
|
||||
|
||||
<sect2>
|
||||
<title>Rebuilding ATA RAID1 Arrays</title>
|
||||
|
||||
<para>&os; supports the ability to hot-replace a failed disk in
|
||||
an array.</para>
|
||||
|
||||
<para>An error indicating a failed disk will appear in
|
||||
<filename>/var/log/messages</filename> or in the &man.dmesg.8;
|
||||
output:</para>
|
||||
|
||||
<programlisting>ad6 on monster1 suffered a hard error.
|
||||
ad6: READ command timeout tag=0 serv=0 - resetting
|
||||
ad6: trying fallback to PIO mode
|
||||
ata3: resetting devices .. done
|
||||
ad6: hard error reading fsbn 1116119 of 0-7 (ad6 bn 1116119; cn 1107 tn 4 sn 11)\\
|
||||
status=59 error=40
|
||||
ar0: WARNING - mirror lost</programlisting>
|
||||
|
||||
<para>Use &man.atacontrol.8; to check for further
|
||||
information:</para>
|
||||
|
||||
<screen>&prompt.root; <userinput>atacontrol list</userinput>
|
||||
ATA channel 0:
|
||||
Master: no device present
|
||||
Slave: acd0 <HL-DT-ST CD-ROM GCR-8520B/1.00> ATA/ATAPI rev 0
|
||||
|
||||
ATA channel 1:
|
||||
Master: no device present
|
||||
Slave: no device present
|
||||
|
||||
ATA channel 2:
|
||||
Master: ad4 <MAXTOR 6L080J4/A93.0500> ATA/ATAPI rev 5
|
||||
Slave: no device present
|
||||
|
||||
ATA channel 3:
|
||||
Master: ad6 <MAXTOR 6L080J4/A93.0500> ATA/ATAPI rev 5
|
||||
Slave: no device present
|
||||
|
||||
&prompt.root; <userinput>atacontrol status ar0</userinput>
|
||||
ar0: ATA RAID1 subdisks: ad4 ad6 status: DEGRADED</screen>
|
||||
|
||||
<procedure>
|
||||
<step>
|
||||
<para>First, detach the ata channel with the failed disk
|
||||
so that it can be safely removed:</para>
|
||||
|
||||
<screen>&prompt.root; <userinput>atacontrol detach ata3</userinput></screen>
|
||||
</step>
|
||||
|
||||
<step>
|
||||
<para>Replace the disk.</para>
|
||||
</step>
|
||||
|
||||
<step>
|
||||
<para>Reattach the ata channel:</para>
|
||||
|
||||
<screen>&prompt.root; <userinput>atacontrol attach ata3</userinput>
|
||||
Master: ad6 <MAXTOR 6L080J4/A93.0500> ATA/ATAPI rev 5
|
||||
Slave: no device present</screen>
|
||||
</step>
|
||||
|
||||
<step>
|
||||
<para>Add the new disk to the array as a spare:</para>
|
||||
|
||||
<screen>&prompt.root; <userinput>atacontrol addspare ar0 ad6</userinput></screen>
|
||||
</step>
|
||||
|
||||
<step>
|
||||
<para>Rebuild the array:</para>
|
||||
|
||||
<screen>&prompt.root; <userinput>atacontrol rebuild ar0</userinput></screen>
|
||||
</step>
|
||||
|
||||
<step>
|
||||
<para>It is possible to check on the progress by issuing the
|
||||
following command:</para>
|
||||
|
||||
<screen>&prompt.root; <userinput>dmesg | tail -10</userinput>
|
||||
[output removed]
|
||||
ad6: removed from configuration
|
||||
ad6: deleted from ar0 disk1
|
||||
ad6: inserted into ar0 disk1 as spare
|
||||
|
||||
&prompt.root; <userinput>atacontrol status ar0</userinput>
|
||||
ar0: ATA RAID1 subdisks: ad4 ad6 status: REBUILDING 0% completed</screen>
|
||||
</step>
|
||||
|
||||
<step>
|
||||
<para>Wait until this operation completes.</para>
|
||||
</step>
|
||||
</procedure>
|
||||
</sect2>
|
||||
</sect1>
|
||||
|
||||
<sect1 id="usb-disks">
|
||||
<sect1info>
|
||||
<authorgroup>
|
||||
|
|
@ -794,7 +443,7 @@ umass0: detached</screen>
|
|||
<title>Creating and Using CD Media</title>
|
||||
|
||||
<indexterm>
|
||||
<primary>CDROMs</primary>
|
||||
<primary>CD-ROMs</primary>
|
||||
<secondary>creating</secondary>
|
||||
</indexterm>
|
||||
|
||||
|
|
@ -912,7 +561,7 @@ umass0: detached</screen>
|
|||
of ways.</para>
|
||||
|
||||
<indexterm>
|
||||
<primary>CDROMs</primary>
|
||||
<primary>CD-ROMs</primary>
|
||||
<secondary>creating bootable</secondary>
|
||||
</indexterm>
|
||||
<para>The last option of general use is <option>-b</option>.
|
||||
|
|
@ -955,7 +604,7 @@ umass0: detached</screen>
|
|||
<title><application>burncd</application></title>
|
||||
|
||||
<indexterm>
|
||||
<primary>CDROMs</primary>
|
||||
<primary>CD-ROMs</primary>
|
||||
<secondary>burning</secondary>
|
||||
</indexterm>
|
||||
<para>For an ATAPI CD burner, <command>burncd</command> can be
|
||||
|
|
@ -1001,7 +650,7 @@ umass0: detached</screen>
|
|||
results like this:</para>
|
||||
|
||||
<indexterm>
|
||||
<primary>CDROMs</primary>
|
||||
<primary>CD-ROMs</primary>
|
||||
<secondary>burning</secondary>
|
||||
</indexterm>
|
||||
<screen>&prompt.root; <userinput>cdrecord -scanbus</userinput>
|
||||
|
|
@ -1122,8 +771,8 @@ scsibus1:
|
|||
<para>It is possible to copy a data CD to an image file that is
|
||||
functionally equivalent to the image file created with
|
||||
&man.mkisofs.8;, and then use it to duplicate any data CD.
|
||||
The example given here assumes that the CDROM device is
|
||||
<devicename>acd0</devicename>. Substitute the correct CDROM
|
||||
The example given here assumes that the CD-ROM device is
|
||||
<devicename>acd0</devicename>. Substitute the correct CD-ROM
|
||||
device.</para>
|
||||
|
||||
<screen>&prompt.root; <userinput>dd if=/dev/acd0 of=file.iso bs=2048</userinput></screen>
|
||||
|
|
@ -1149,7 +798,7 @@ scsibus1:
|
|||
&man.mount.8; that the file system is of type
|
||||
<literal>ISO9660</literal> by specifying
|
||||
<option>-t cd9660</option> to &man.mount.8;. For example,
|
||||
to mount the CDROM device, <filename>/dev/cd0</filename>,
|
||||
to mount the CD-ROM device, <filename>/dev/cd0</filename>,
|
||||
under <filename class="directory">/mnt</filename>,
|
||||
use:</para>
|
||||
|
||||
|
|
@ -1162,7 +811,7 @@ scsibus1:
|
|||
|
||||
<screen>&prompt.root; <userinput>mount_cd9660 /dev/cd0 /mnt</userinput></screen>
|
||||
|
||||
<para>While data CDROMs from any vendor can be mounted this way,
|
||||
<para>While data CD-ROMs from any vendor can be mounted this way,
|
||||
disks with certain ISO 9660 extensions might behave oddly.
|
||||
For example, Joliet disks store all filenames in two-byte
|
||||
Unicode characters. The &os; kernel does not speak Unicode,
|
||||
|
|
@ -1186,13 +835,13 @@ scsibus1:
|
|||
</note>
|
||||
|
||||
<para>Occasionally, <errorname>Device not configured</errorname>
|
||||
will be displayed when trying to mount a CDROM. This
|
||||
usually means that the CDROM drive thinks that there is no
|
||||
will be displayed when trying to mount a CD-ROM. This
|
||||
usually means that the CD-ROM drive thinks that there is no
|
||||
disk in the tray, or that the drive is not visible on the bus.
|
||||
It can take a couple of seconds for a CDROM drive to realize
|
||||
It can take a couple of seconds for a CD-ROM drive to realize
|
||||
that a media is present, so be patient.</para>
|
||||
|
||||
<para>Sometimes, a SCSI CDROM may be missed because it did not
|
||||
<para>Sometimes, a SCSI CD-ROM may be missed because it did not
|
||||
have enough time to answer the bus reset. To resolve this,add
|
||||
the following option to the kernel configuration and <link
|
||||
linkend="kernelconfig-building">rebuild the
|
||||
|
|
@ -1201,7 +850,7 @@ scsibus1:
|
|||
<programlisting>options SCSI_DELAY=15000</programlisting>
|
||||
|
||||
<para>This tells the SCSI bus to pause 15 seconds during boot,
|
||||
to give the CDROM drive every possible chance to answer the
|
||||
to give the CD-ROM drive every possible chance to answer the
|
||||
bus reset.</para>
|
||||
</sect2>
|
||||
|
||||
|
|
@ -1220,7 +869,7 @@ scsibus1:
|
|||
|
||||
<screen>&prompt.root; <userinput>tar xzvf /dev/acd1</userinput></screen>
|
||||
|
||||
<para>This type of disk can not be mounted as a normal CDROM and
|
||||
<para>This type of disk can not be mounted as a normal CD-ROM and
|
||||
the data cannot be read under any operating system except
|
||||
&os;. In order to mount the CD, or to share the data with
|
||||
another operating system, &man.mkisofs.8; must be used as
|
||||
|
|
@ -1968,105 +1617,6 @@ cd0: Attempt to query device size failed: NOT READY, Medium not present - tray c
|
|||
</sect2>
|
||||
</sect1>
|
||||
|
||||
<sect1 id="backups-floppybackups">
|
||||
<title>Backups to Floppies</title>
|
||||
|
||||
<sect2 id="floppies-using">
|
||||
<title>Can I Use Floppies for Backing Up My Data?</title>
|
||||
|
||||
<indexterm><primary>backup floppies</primary></indexterm>
|
||||
<indexterm><primary>floppy disks</primary></indexterm>
|
||||
|
||||
<para>Floppy disks are not a suitable media for making backups
|
||||
as:</para>
|
||||
|
||||
<itemizedlist>
|
||||
<listitem>
|
||||
<para>The media is unreliable, especially over long periods
|
||||
of time.</para>
|
||||
</listitem>
|
||||
|
||||
<listitem>
|
||||
<para>Backing up and restoring is very slow.</para>
|
||||
</listitem>
|
||||
|
||||
<listitem>
|
||||
<para>They have a very limited capacity.</para>
|
||||
</listitem>
|
||||
</itemizedlist>
|
||||
|
||||
<para>However, if no other method of backing up data is
|
||||
available, floppy disks are better than no backup at
|
||||
all.</para>
|
||||
|
||||
<para>When backing up to floppy disks, ensure the floppies are
|
||||
of good quality. Floppies that have been lying around the
|
||||
office for a couple of years are a bad choice. Ideally,
|
||||
use new ones from a reputable manufacturer.</para>
|
||||
</sect2>
|
||||
|
||||
<sect2 id="floppies-creating">
|
||||
<title>So How Do I Backup My Data to Floppies?</title>
|
||||
|
||||
<para>The best way to backup to floppy disk is to use
|
||||
&man.tar.1; with <option>-M</option> (multi-volume), which
|
||||
allows backups to span multiple floppies.</para>
|
||||
|
||||
<para>To backup all the files in the current directory and
|
||||
sub-directory, use this as <username>root</username>:</para>
|
||||
|
||||
<screen>&prompt.root; <userinput>tar Mcvf /dev/fd0 *</userinput></screen>
|
||||
|
||||
<para>When the first floppy is full, &man.tar.1; will prompt
|
||||
to insert the next volume, which in this case is the next
|
||||
floppy disk:</para>
|
||||
|
||||
<screen>Prepare volume #2 for /dev/fd0 and hit return:</screen>
|
||||
|
||||
<para>This is repeated, with the volume number incrementing,
|
||||
until all the specified files have been archived.</para>
|
||||
</sect2>
|
||||
|
||||
<sect2 id="floppies-compress">
|
||||
<title>Can I Compress My Backups?</title>
|
||||
|
||||
<indexterm>
|
||||
<primary><command>tar</command></primary>
|
||||
</indexterm>
|
||||
<indexterm>
|
||||
<primary><command>gzip</command></primary>
|
||||
</indexterm>
|
||||
<indexterm><primary>compression</primary></indexterm>
|
||||
|
||||
<para>Unfortunately, &man.tar.1; does not support
|
||||
<option>-z</option> for multi-volume archives. Instead,
|
||||
&man.gzip.1; all the files, &man.tar.1; them to the floppies,
|
||||
then &man.gunzip.1; the files.</para>
|
||||
</sect2>
|
||||
|
||||
<sect2 id="floppies-restoring">
|
||||
<title>How Do I Restore My Backups?</title>
|
||||
|
||||
<para>To restore the entire archive use:</para>
|
||||
|
||||
<screen>&prompt.root; <userinput>tar Mxvf /dev/fd0</userinput></screen>
|
||||
|
||||
<para>There are two methods to restore only specific files. The
|
||||
first is to insert the first floppy and use:</para>
|
||||
|
||||
<screen>&prompt.root; <userinput>tar Mxvf /dev/fd0 <replaceable>filename</replaceable></userinput></screen>
|
||||
|
||||
<para>&man.tar.1; will prompt to insert subsequent floppies
|
||||
until it finds the required file.</para>
|
||||
|
||||
<para>Alternatively, if the floppy containing the file is known,
|
||||
insert that floppy and use the same command. If the first
|
||||
file on the floppy is a continuation from the previous one,
|
||||
&man.tar.1; will warn that it cannot restore it, even if you
|
||||
have not asked it to.</para>
|
||||
</sect2>
|
||||
</sect1>
|
||||
|
||||
<sect1 id="backup-strategies">
|
||||
<sect1info>
|
||||
<authorgroup>
|
||||
|
|
@ -2476,7 +2026,7 @@ cd0: Attempt to query device size failed: NOT READY, Medium not present - tray c
|
|||
<note>
|
||||
<para>Livefs CD images are not available for
|
||||
&os; &rel.current;-RELEASE and later. In addition to
|
||||
the CDROM installation images, flash drive installation
|
||||
the CD-ROM installation images, flash drive installation
|
||||
images may be used to recover a system. The
|
||||
<quote>memstick</quote> image for
|
||||
&os;/&arch.i386; &rel.current;-RELEASE is available
|
||||
|
|
@ -2517,10 +2067,10 @@ cd0: Attempt to query device size failed: NOT READY, Medium not present - tray c
|
|||
<quote>livefs</quote> CD and boot the computer. The
|
||||
original install menu will be displayed on the screen.
|
||||
Select the correct country, then choose
|
||||
<guimenuitem>Fixit -- Repair mode with CDROM/DVD/floppy or
|
||||
<guimenuitem>Fixit -- Repair mode with CD-ROM/DVD/floppy or
|
||||
start a shell.</guimenuitem> then select
|
||||
<guimenuitem>CDROM/DVD -- Use the live filesystem
|
||||
CDROM/DVD</guimenuitem>.
|
||||
<guimenuitem>CD-ROM/DVD -- Use the live filesystem
|
||||
CD-ROM/DVD</guimenuitem>.
|
||||
<command>restore</command> and the other needed programs
|
||||
are located in <filename
|
||||
class="directory">/mnt2/rescue</filename>.</para>
|
||||
|
|
|
|||
Loading…
Reference in a new issue