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flash-linux0.11-talk/一些非必要的资料/linux-0.11-quickstart-debug/Bochs-2.3.6/docs/user/harddisk-modes.html

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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<HTML
><HEAD
><TITLE
>Disk Image Modes</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK
REL="HOME"
TITLE="Bochs User Manual"
HREF="index.html"><LINK
REL="UP"
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HREF="howto.html"><LINK
REL="PREVIOUS"
TITLE="Notes about Cirrus SVGA usage"
HREF="cirrus-notes.html"><LINK
REL="NEXT"
TITLE="Using the bximage tool"
HREF="using-bximage.html"></HEAD
><BODY
CLASS="SECTION"
BGCOLOR="#FFFFFF"
TEXT="#000000"
LINK="#0000FF"
VLINK="#840084"
ALINK="#0000FF"
><DIV
CLASS="NAVHEADER"
><TABLE
SUMMARY="Header navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>Bochs User Manual</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="cirrus-notes.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
>Chapter 8. Tips and Techniques</TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="using-bximage.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="SECTION"
><H1
CLASS="SECTION"
><A
NAME="HARDDISK-MODES"
>8.18. Disk Image Modes</A
></H1
><P
>Bochs can handle independent disk image format for each
disk present on the ata interfaces.
The disk image type is selected in the configuration file
by the "mode" option of the ataX-xxx directives.
Example:
<TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><PRE
CLASS="SCREEN"
>ata0-master: type=disk, mode=flat, path=10M.sample, cylinders=306, heads=4, spt=17</PRE
></TD
></TR
></TABLE
></P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
>If unspecified, the default "mode" is flat. </P
></BLOCKQUOTE
></DIV
><P
><DIV
CLASS="TABLE"
><A
NAME="AEN3348"
></A
><P
><B
>Table 8-3. Supported Disk Modes</B
></P
><TABLE
BORDER="1"
RULES="all"
CLASS="CALSTABLE"
><COL><COL><COL><THEAD
><TR
><TH
>Name</TH
><TH
>Description</TH
><TH
>Features</TH
></TR
></THEAD
><TBODY
><TR
><TD
> flat </TD
><TD
> one file, flat layout </TD
><TD
>
accessible with mtools or winimage-like tools
</TD
></TR
><TR
><TD
> concat </TD
><TD
> multiple files, concatenated </TD
><TD
>
mappable to contained partitions
</TD
></TR
><TR
><TD
> external </TD
><TD
> accessed through an external C++ class </TD
><TD
>
developer specific, needs a C++ class at compile time
</TD
></TR
><TR
><TD
> dll </TD
><TD
> accessed through a DLL </TD
><TD
>
developer specific, windows only
</TD
></TR
><TR
><TD
> sparse </TD
><TD
> up to 10 layers stackable files </TD
><TD
>
commitable, rollbackable, growing
</TD
></TR
><TR
><TD
> vmware3 </TD
><TD
> vmware3 disk support </TD
><TD
>
vmware version 3 compatibility
</TD
></TR
><TR
><TD
> vmware4 </TD
><TD
> vmware4 disk support </TD
><TD
>
vmware version 4 compatibility
</TD
></TR
><TR
><TD
> undoable </TD
><TD
> flat file with a commitable redolog </TD
><TD
>
commitable, rollbackable
</TD
></TR
><TR
><TD
> growing </TD
><TD
> one growing file </TD
><TD
> growing
</TD
></TR
><TR
><TD
> volatile </TD
><TD
> flat file with a volatile redolog </TD
><TD
>
always rollbacked
</TD
></TR
></TBODY
></TABLE
></DIV
></P
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="HARDDISK-MODE-FLAT"
>8.18.1. flat</A
></H2
><P
></P
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3400"
>8.18.1.1. description</A
></H3
><P
>In flat mode, all sectors of the harddisk are stored in one flat file,
in lba order. </P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3403"
>8.18.1.2. image creation</A
></H3
><P
>Flat disk images can be created with the bximage utility
(see <A
HREF="using-bximage.html"
>Section 8.19</A
> for more information).</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3407"
>8.18.1.3. path</A
></H3
><P
>The "path" option of the ataX-xxx directive in the configuration file
must point to the flat image file.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="HARDDISK-MODE-FLAT-TOOLS"
>8.18.1.4. external tools</A
></H3
><P
>Flat images content can be accessed from the host by the
following tools :
<P
></P
><UL
><LI
><P
> mtools (see <A
HREF="mtools.html"
>Section 8.2</A
>)</P
></LI
><LI
><P
> mount with a loopback (see <A
HREF="loop-device-usage.html"
>Section 8.7</A
>) </P
></LI
><LI
><P
> Winimage / DiskExplorer (see <A
HREF="winimage.html"
>Section 8.4</A
>) </P
></LI
><LI
><P
> Bochs Tools (see <A
HREF="bochs-linux-disktools.html"
>Section 8.3</A
>) </P
></LI
></UL
></P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3426"
>8.18.1.5. typical use</A
></H3
><P
>Flat mode is Bochs default harddisk layout. This is also
the layout of disk images provided on Bochs websites.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3429"
>8.18.1.6. limitations</A
></H3
><P
>On some host OSes, Bochs flat disk images are limited to 2GiB.</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="AEN3432"
>8.18.2. concat</A
></H2
><P
></P
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3435"
>8.18.2.1. description</A
></H3
><P
>In concat mode, all sectors of the harddisk are stored in several flat files,
in lba order. </P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3438"
>8.18.2.2. image creation</A
></H3
><P
>Disk images for the usage in 'concat' mode can be created with the bximage
utility (see <A
HREF="using-bximage.html"
>Section 8.19</A
> for more information).</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3442"
>8.18.2.3. path</A
></H3
><P
>The "path" option of the ataX-xxx directive in the configuration file
must point to the first file (e.g. win95-1). The lower layer files names are
found by adding 1 to the last character (e.g. win95-2, win95-3, etc.).</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3445"
>8.18.2.4. external tools</A
></H3
><P
>If every single file contains a complete partition, they can be accessed
with same tools as the 'flat' mode images.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3448"
>8.18.2.5. typical use</A
></H3
><P
>If the partition sizes and file sizes are set up correctly, this allows you to
store each partition in a separate file, which is very convenient if you want
to operate on a single partition (e.g. mount with loopback, create filesystem,
fsck, etc.).</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3451"
>8.18.2.6. limitations</A
></H3
><P
>On some host OSes, there is a limit of 2GiB per file.</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="AEN3454"
>8.18.3. external/dll</A
></H2
><P
></P
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3457"
>8.18.3.1. description</A
></H3
><P
>This mode is only useful for developers and needs an additional C++ class
compiled in, or an additional DLL linked to Bochs.</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="AEN3460"
>8.18.4. sparse</A
></H2
><P
></P
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3463"
>8.18.4.1. description</A
></H3
><P
> Sparse disk support has been added by JustinSB. Sparse disk features are:
<P
></P
><UL
><LI
><P
> Large hard drive can be created, and only used space will be stored
in the file. In practice, on Unix, this is not a large gain as it is
done anyway.
</P
></LI
><LI
><P
> Multiple sparse drive images can be mounted on top of each other.
Writes go to the top image. This allows several similar configurations
to share a master "base" file, and also allows filesystem rollback or
no-write options. Up to 10 disk images can be layered on top of each other.
</P
></LI
></UL
></P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3471"
>8.18.4.2. image creation</A
></H3
><P
>Sparse disk images must be created with the bximage utility
(see <A
HREF="using-bximage.html"
>Section 8.19</A
> for more information).
Be sure to enter "sparse" when selecting the image type.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3475"
>8.18.4.3. path</A
></H3
><P
>The "path" option of the ataX-xxx directive in the configuration file
must point to the top layered file. The lower layer files names are found by
substracting 1 from the last character (must be a digit)</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3478"
>8.18.4.4. external tools</A
></H3
><P
>No external tool support Sparse disk images yet.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3481"
>8.18.4.5. typical use</A
></H3
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3483"
>8.18.4.5.1. Space Saving</A
></H4
><P
> Create a sparse disk image using bximage. Set size to eg 10GB.
Only allocated space will be stored,
so your drive image should be only about as large as the files stored on it.
</P
></DIV
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3486"
>8.18.4.5.2. Disk Rollback</A
></H4
><P
> <P
></P
><UL
><LI
><P
> Create a sparse disk image called "c.img.0". Point .bochsrc at "c.img.0".
In bochs, install your favourite OS. Switch off bochs.
</P
></LI
><LI
><P
> Create a sparse disk image (of the same size)
and name it "c.img.1". Point .bochsrc at "c.img.1"
"c.img.0" is visible, but all writes go to "c.img.1".
After using bochs, you can simply delete
"c.img.1" to undo changes and go back to a clean OS install.
</P
></LI
></UL
>
</P
></DIV
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3494"
>8.18.4.5.3. Disk Optional Commit</A
></H4
><P
> <P
></P
><UL
><LI
><P
> Create a sparse disk image called "c.img.0". Point .bochsrc at "c.img.0".
In bochs, install your favourite OS. Switch off bochs.
</P
></LI
><LI
><P
> Create a sparse disk image (of the same size) and name it "c.img.1".
Point .bochsrc at "c.img.1"
"c.img.0" is visible, but all writes go to "c.img.1".
After using bochs, if you want to keep the
changes, use the (currently non-existant) merge utility
to make a single unified drive image.
</P
></LI
><LI
><P
> Alternatively simply create a new partition on top called "c.img.2".
</P
></LI
></UL
>
</P
></DIV
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3504"
>8.18.4.5.4. Common Base</A
></H4
><P
></P
><UL
><LI
><P
> Create a sparse disk image called "base.img". Point .bochsrc at "base.img".
In bochs, install your favourite OS. Switch off bochs.
</P
></LI
><LI
><P
> Create a sparse disk image (of the same size) and name it "www.img.1".
Make "wwww.img.0" a symlink to
"base.img". Point .bochsrc at "www.img.1". Using bochs, install a webserver.
</P
></LI
><LI
><P
> Create a symlink to "base.img" called "db.img.0".
Create a sparse disk image (of the same size)
and name it "db.img.1". Point .bochsrc at "db.img.1".
Using bochs, install a database server.
</P
></LI
></UL
><P
> Now both a database server and webserver can be
run in separate virtual machines, but they share the common OS image,
saving drive space.
</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3514"
>8.18.4.6. limitations</A
></H3
><P
> There is a need for supporting utilities (yet unwritten) :
<P
></P
><UL
><LI
><P
>to merge two sparse disk images into a single image </P
></LI
><LI
><P
>to defragment a sparse disk image and remove unused space </P
></LI
></UL
></P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="AEN3522"
>8.18.5. vmware3/vmware4</A
></H2
><P
></P
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3525"
>8.18.5.1. description</A
></H3
><P
>Sharvil Nanavati has added vmware3/4 disk image support into Bochs
for Net Integration Technologies, Inc.
You should be able to use disk images created by vmware version 3 and 4.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3528"
>8.18.5.2. image creation</A
></H3
><P
>Create such disk image with vmware version 3 or 4.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3531"
>8.18.5.3. path</A
></H3
><P
>The "path" option of the ataX-xxx directive in the configuration file
must point to the vmware3/4 disk image.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3534"
>8.18.5.4. external tools</A
></H3
><P
><IMG
SRC="../images/undercon.png"> give a look at vmware3/4 tools : disk image creation, etc.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3538"
>8.18.5.5. typical use</A
></H3
><P
>If you want to use an existing vmware3/4 disk image.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3541"
>8.18.5.6. limitations</A
></H3
><P
>Only vmware versions 3 and 4 disk image files are supported.</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="AEN3544"
>8.18.6. undoable</A
></H2
><P
></P
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3547"
>8.18.6.1. description</A
></H3
><P
> Undoable disks are commitable/rollbackable disk images.
An undoable disk is based on a read-only flat image
(see <A
HREF="harddisk-modes.html#HARDDISK-MODE-FLAT"
>Section 8.18.1</A
>), associated with
a growing redolog, that contains all changes (writes)
made to the flat image content. </P
><P
> This redolog is dynamically created at runtime, if it does not
previously exists.</P
><P
> All writes go to the redolog, reads are done from the
redolog if previously written, or from the flat file
otherwise.</P
><P
> If unspecified with the "journal" option of the ataX-xxx directive,
the redolog file name is created by adding a ".redolog"
suffix to the flat image name.</P
><P
> File size of the redolog can grow up to the total disk
size plus a small overhead due to internal data managment
(about 3% for a 32MiB disk,
less than 0.5% for a 2GiB disk).</P
><P
> After a run, the redolog will still be present, so the changes
are still visible the next time you run Bochs with this disk image.</P
><P
> After a run, the redolog can be committed (merged)
to the flat image with the bxcommit utility.</P
><P
> After a run, the redolog can be rollbacked (discarded)
by simply deleting the redolog file.</P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
> In this mode, the flat file is always open in read-only mode,
so it can safely be stored on a read-only medium (for example on a cdrom).</P
></BLOCKQUOTE
></DIV
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3560"
>8.18.6.2. image creation</A
></H3
><P
>The flat disk images must be created with the bximage utility
(see <A
HREF="using-bximage.html"
>Section 8.19</A
> for more information).
The growing redolog is created automatically if needed.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3564"
>8.18.6.3. path</A
></H3
><P
> The "path" option of the ataX-xxx directive in the configuration file
must be the flat image name. The redolog name can be set with the "journal"
option of the same directive.
If not set, the redolog name is created by adding the
".redolog" suffix to the flat image name.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3567"
>8.18.6.4. external tools</A
></H3
><P
> See <A
HREF="harddisk-modes.html#HARDDISK-MODE-FLAT-TOOLS"
>Section 8.18.1.4</A
> for tools
to access the flat disk image content.</P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
> The up-to-date content can only be seen after you commit the redolog
to the flat file with the bxcommit utility.</P
></BLOCKQUOTE
></DIV
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3573"
>8.18.6.5. typical use</A
></H3
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3577"
>8.18.6.5.1. Commit</A
></H4
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
></DIV
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3581"
>8.18.6.5.2. Rollback</A
></H4
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
></DIV
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3585"
>8.18.6.5.3. Common Base</A
></H4
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
></DIV
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3589"
>8.18.6.5.4. Harddisk Image on a Read-Only Medium</A
></H4
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3593"
>8.18.6.6. limitations</A
></H3
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="AEN3597"
>8.18.7. growing</A
></H2
><P
></P
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3600"
>8.18.7.1. description</A
></H3
><P
> Growing disk images start as a small files, and
grow whenever new data is written to them.
</P
><P
> Once a sector is
written in the growing file, subsequent writes to the same
sector will happen in place.
</P
><P
> File size of Growing disk images can go up to the total disk
size plus a small overhead due to internal data managment.
(about 3% for a 32MiB disk,
less than 0.5% for a 2GiB disk).
</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3605"
>8.18.7.2. image creation</A
></H3
><P
>Growing disk images must be created with the bximage utility
(see <A
HREF="using-bximage.html"
>Section 8.19</A
> for more information).
Be sure to enter "growing" when selecting the image type.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3609"
>8.18.7.3. path</A
></H3
><P
> The "path" option of the ataX-xxx directive in the configuration file
must be the growing image name. </P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3612"
>8.18.7.4. external tools</A
></H3
><P
>No external tool support Growing disk images yet.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3615"
>8.18.7.5. typical use</A
></H3
><P
>Growing disk images can be used whenever you want to maximize disk space.
However, please note that Bochs will not check if enough disk space is available
before writing new data. If no disk space is available, a panic will occur.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3618"
>8.18.7.6. limitations</A
></H3
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H2
CLASS="SECTION"
><A
NAME="AEN3622"
>8.18.8. volatile</A
></H2
><P
></P
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3625"
>8.18.8.1. description</A
></H3
><P
> Volatile disks are always-rollbacked disk images.
An volatile disk is based on a read-only flat image
(see <A
HREF="harddisk-modes.html#HARDDISK-MODE-FLAT"
>Section 8.18.1</A
>), associated with
a growing temporary redolog, that contains all changes (writes)
made to the flat image content. All data written to
the disk image are lost at the end of the Bochs
session.</P
><P
> The redolog is dynamically created at runtime, when
Bochs starts, and is deleted when Bochs closes (win32)
or just after it has been created (Unix).</P
><P
> All writes go to the redolog, reads are done from the
redolog if previously written, or from the flat file
otherwise.</P
><P
> If unspecified with the "journal" option of the ataX-xxx directive,
the redolog file name is created by adding a ".redolog"
suffix to the flat image name.</P
><P
> File size of the redolog can grow up to the total disk
size plus a small overhead due to internal data managment
(about 3% for a 32MiB disk,
less than 0.5% for a 2GiB disk).</P
><P
> After a run, the redolog is not any more present, so the changes
are discarded.</P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
> In this mode, the flat file is always open in read-only mode,
so it can safely be stored on a read-only medium (for example on a cdrom).</P
></BLOCKQUOTE
></DIV
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3636"
>8.18.8.2. image creation</A
></H3
><P
>The flat disk images must be created with the bximage utility
(see <A
HREF="using-bximage.html"
>Section 8.19</A
> for more information).
The growing redolog is created automatically.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3640"
>8.18.8.3. path</A
></H3
><P
> The "path" option of the ataX-xxx directive in the configuration file
must be the flat image name. The redolog name can be set with the "journal"
option of the same directive.
If not set, the redolog name is created by adding the
".redolog" suffix to the flat image name.
A random suffix is also appended to the redolog name.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3643"
>8.18.8.4. external tools</A
></H3
><P
> See <A
HREF="harddisk-modes.html#HARDDISK-MODE-FLAT-TOOLS"
>Section 8.18.1.4</A
> for tools
to access the flat disk image content.</P
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3647"
>8.18.8.5. typical use</A
></H3
><P
><IMG
SRC="../images/undercon.png"> can be completed</P
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3651"
>8.18.8.5.1. Repeatable simulations</A
></H4
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
></DIV
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3655"
>8.18.8.5.2. Multiple Bochs instances</A
></H4
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
></DIV
><DIV
CLASS="SECTION"
><H4
CLASS="SECTION"
><A
NAME="AEN3659"
>8.18.8.5.3. Harddisk Image on a Read-Only Medium</A
></H4
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
></DIV
></DIV
><DIV
CLASS="SECTION"
><H3
CLASS="SECTION"
><A
NAME="AEN3663"
>8.18.8.6. limitations</A
></H3
><P
><IMG
SRC="../images/undercon.png"> to be completed</P
></DIV
></DIV
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