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<ARTICLE>
<TITLE>Jaz-drive HOWTO</TITLE>
<AUTHOR>Herbert S. DaSilva</AUTHOR>
<date>v1.8, 12 January 2000</date>
<ABSTRACT>This HOWTO covers the configuration and use of the 1Gb and 2Gb
 Iomega Jaz drives under Linux.</ABSTRACT>
<TOC>


<SECT>Introduction<label id="Introduction" >

<P>The Iomega Jaz drive is a removable-media disk drive whose disks have a
 capacity of 1 or 2 Gigabytes. Unlike the Zip drive, the Jaz is only
 available as a SCSI device (internal or external), so a SCSI interface card
 and driver are required to use these drives.</P>


<SECT1>History<label id="History" >

<P>Much of this HOWTO evolved from what was created by the previous author,
 Bob Willmot, (who can now be reached at
 <url url="mailto:bob@willmot.com" name="bob@willmot.com">), who maintained
 the HOWTO through version 1.6, with contributions and information from the
 following people:</P>

<P><ITEMIZE>
 <ITEM>Grant Gunther, grant@torque.net
 <ITEM>Tom Poindexter, tpoindex@nyx.net
 <ITEM>Todd Woods, woods@cs.uiowa.edu
 <ITEM>Richard B. Melrose, rbm@math.mit.edu
 <ITEM>Phil Howard, phil@charon.milepost.com
 <ITEM>Rick Niess, rniess@ocean.st.usm.edu
</ITEMIZE></P>


<SECT1>Latest Version

<P>The latest version of this document can be found on my homepage
 <url url="http://www.ultranet.com/~hsd/HOWTO/" name="http://www.ultranet.com/~hsd/HOWTO/">
 where you will find the HTML version, suitable for browsing, a PostScript
 version, suitable for printing, and the SGML source.
 Other versions may be found in different formats at the LDP homepage
 <url url="http://www.linuxdoc.org/" name="http://www.linuxdoc.org/">.</P>


<SECT2>Version History

<P>v1.8, 12 January 2000
<ITEMIZE>
 <ITEM>Fixed an incorrect HTTP link
 <ITEM>Added clarification to jaztool code for 2Gb drives
</ITEMIZE></P>

<P>v1.7, 18 November 1999
<ITEMIZE>
 <ITEM>Converted to SGML
 <ITEM>Added info for 2Gb drives
 <ITEM>Added fstab entry examples
 <ITEM>General freshening up
</ITEMIZE></P>

<P>If you have any comments/suggestions/corrections please send them to:
 Herb DaSilva <url url="mailto:hsd@ma.ultranet.com" name="at Home"> or
 (if you <EM>must</EM> have fast response)
 <url url="mailto:herb@aoainc.com" name="at Work">.</P>


<SECT1>Copyrights and Trademarks

<P>Copyright &copy; 2000,1999 Herbert S. DaSilva</P>

<P>This manual may be reproduced in whole or in part, without fee, subject
 to the following restrictions:</P>

<P><ITEMIZE>
 <ITEM>The copyright notice above and this permission notice must be
  preserved complete on all complete or partial copies
 <ITEM>Any translation or derived work must be approved by the author in
  writing before distribution.
 <ITEM>If you distribute this work in part, instructions for obtaining the
  complete version of this manual must be included, and a means for obtaining
  a complete version provided.
 <ITEM>Small portions may be reproduced as illustrations for reviews or
  quotes in other works without this permission notice if proper citation is
  given.
</ITEMIZE></P>

<P>Exceptions to these rules may be granted for academic purposes: Write to
 the author and ask. These restrictions are here to protect us as authors,
 not to restrict you as learners and educators. All source code in this
 document is placed under the GNU General Public License, available via
 anonymous FTP from
 <url url="ftp://prep.ai.mit.edu/pub/GNU/COPYING" name="the GNU archive site">.
</P>


<SECT1>Acknowledgements and Thanks

<P>Thanks to Stephan Burlot, stephan.burlot@edicom.ch, for pointing out
 the error (or lack of clarity) in the 2Gb patch to jaztool that was
 fixed in version 1.8.</P>

<P>My thanks go out to Mark F. Komarinski for his "HOWTO-HOWTO" - This
 LDP author was helped Mark, you did your job.  ;-)</P>


<SECT>Jaz Hardware

<SECT1>The Jaz Drives

<P>Jaz drives are SCSI devices and are available as an external drive
 with a 50-pin SCSI-2 self-terminating interface or an internal 3-1/2
 format drive with a 50-pin header interface.</P>

<P>Both the internal and external devices are available in either
 1 or 2 Gigabyte capacity, so there are four different Jaz drives
 available.</P>


<SECT1>The Jaz "Disks"

<P>Jaz disks are a cartridge-style removable media containing a stack
 of three 3.5" platters.  From here out, I'll be using the terms
 "cartridge" and "disk" interchangeably to mean the Jaz media.</P>

<P>The 1Gb and 2Gb cartridges appear similar, but there is actually a
 subtle difference in their shape which prevents a 2Gb cartridge from
 being fully inserted into a 1Gb drive.  Obviously, this means that
 you can't use a 2Gb cartridge in a 1Gb drive.</P>

<P>The 2-Gb capacity Jaz drives can read, write, and format both 2-Gb
 and 1-Gb Jaz cartridges.</P>


<SECT1>The Jaz Jet Host Adapter

<P>Iomega markets a SCSI host adapter under the name Jaz Jet.  However,
 there are at least two different SCSI chipsets that are used.  For this
 reason, the Jaz Jet isn't necessarily the best SCSI adapter to buy if
 you need one for your Jaz drive.  You're better off getting a card that
 you <EM>know</EM> your Linux distribution will support (see the next section).

<P>One of the Jaz Jet cards is based on the Adaptec 7800 family of adapters.
 Linux 2.0 supports this adapter with the aic7xxx driver. This driver is built
 into most of the standard 2.x SCSI-capable kernels supplied with most Linux
 distributions.</P>

<P>The other adapter is based on the Advanced Systems chipset.  At boot
 time the board gives a message like:</P>

<P><TT>Jaz Jet PCI SCSI adapter Copyright Advanced Systems 1996</TT></P>

<P>Depending on your Linux distribution, you may need to build a custom
 kernel (with the CONFIG_SCSI_ADVANSYS variable set) to use this adapter.</P>

<P>Personally, I don't like surprises, so if I were going to buy an adapter
 card, I would get a name-brand card with a 50-pin connector, so that I knew
 that what I was getting was supported.</P>


<SECT1>Other SCSI Host Adapters

<P>If you're using an Ultra-Wide SCSI card with a 68-pin connector, you'll
 need to get an adapter or another cable. The adapters do indeed work just
 fine with the Jaz drive, but can be rather pricey, so if you're buying a
 SCSI card primarily for the purpose of connecting the Jaz drive, you're
 better off picking up a card with a 50pin connector on it.</P>

<P>If you're looking for a suggestion, I like the Adaptec AHA-2930U - it's
 cheap, it's fast, and the Jaz drive just plugs right in using the supplied
 cable with no adapter hassles.  Unfortunately, support for this card is
 fairly new, so unless you have a fairly new Linux distribution (2.2.x
 kernel), it probably isn't supported.  There are patches to the aic7xxx
 driver for 2.0.36 kernels that support this card, however.  The AHA-2940U
 is an excellent choice as well, and it has been supported for a lot longer,
 it's just more expensive.</P>


<SECT1>Kernel Driver Issues

<P>As always, be sure that your Linux distribution supports a particular card
 EXPLICITLY before making a purchase.  Many manufacturers, like Adaptec, have
 cards with numbers and letters <EM>similar</EM> to each other that are
 actually <EM>completely different chipsets</EM>, and therefore use
 <EM>completely different drivers</EM>.</P>

<P>Configuring the Linux kernel for a SCSI card is the subject of a complete
 document in itself, so I won't go into that here.</P>

<P>Info on rebuilding the kernel should be found in /usr/src/linux/README,
 or in /usr/src/linux/Documentation/ directory for the 2.x kernels.
 If these files don't exist, make sure that you have installed the kernel
 package source for your distribution.</P>

<P>You can also check out
 <url url="http://metalab.unc.edu/mdw/HOWTO/Kernel-HOWTO.html" name=" Brian Ward's Kernel-HOWTO"></P>


<SECT>Identifying the Jaz Drive

<SECT1>During Power-On Test

<P>With a SCSI controller installed, when the machine is powered up or reset
 the SCSI controller will scan the SCSI bus looking for attached devices
 before booting the operating system.</P>

<P>If your SCSI card is correctly installed, and your Jaz drive is attached
 and powered on, you should see the drive listed as something like "Iomega
 Jaz 1GB" or "Iomega Jaz 2GB" during this time.</P>

<P>If the drive doesn't show up, there's no sense booting Linux.  Power down
 the PC and Jaz drive, and check everything again.  In particular, unplug the
 cables and make sure none of the pins are bent, then replug them and
 ensure they are completely seated against the connector.  If you have
 multiple SCSI devices, make sure they all have different ID numbers, and
 that the last device in the SCSI chain is terminated.</P>

<P>When the drive shows up in the power-on test, you're half way home.</P>


<SECT1>During Boot

<P>When Linux boots the SCSI driver should display information about your
 SCSI adapter and what devices are attached to the SCSI bus.</P>

<P>Boot messages will vary depending on your driver and adapter, and are logged
 to the /var/log/messages (or /var/adm/messages) file as well as appearing on
 the screen during boot.  You can also 'replay' the messages since your last
 boot from the command prompt with the <TT>dmesg</TT> command.</P>

<P>Here's the kernel booting output from a 2.0.36 kernel with an 
 Adaptec 2940 controller (using the aic7xxx driver):

<verb>
    (scsi0) <Adaptec AHA-2940A Ultra SCSI host adapter> found at PCI 14/0
    (scsi0) Narrow Channel, SCSI ID=7, 3/255 SCBs
    (scsi0) Warning - detected auto-termination
    (scsi0) Please verify driver detected settings are correct.
    (scsi0) If not, then please properly set the device termination
    (scsi0) in the Adaptec SCSI BIOS by hitting CTRL-A when prompted
    (scsi0) during machine bootup.
    (scsi0) Cables present (Int-50 NO, Ext-50 YES)
    (scsi0) Downloading sequencer code... 419 instructions downloaded
    scsi0 : Adaptec AHA274x/284x/294x (EISA/VLB/PCI-Fast SCSI) 5.1.2/3.2.4
           <Adaptec AHA-2940A Ultra SCSI host adapter>
    scsi : 1 host.
      Vendor: iomega    Model: jaz 2GB           Rev: E.17
      Type:   Direct-Access                      ANSI SCSI revision: 02
    Detected scsi removable disk sda at scsi0, channel 0, id 4, lun 0
    scsi : detected 1 SCSI disks total.
    (scsi0:0:4:0) Synchronous at 10.0 Mbyte/sec, offset 15.
    sda : READ CAPACITY failed.
    sda : status = 1, message = 00, host = 0, driver = 28 
    sda : extended sense code = 2 
    sda : block size assumed to be 512 bytes, disk size 1GB.  
</verb></P>

<P>If something resembling these lines doesn't appear, then your kernel is
 probably not configured correctly (or you picked the wrong pre-built
 kernel).</P>

<P>If the "scsi0 :" line does not appear, then you have not configured your
 driver correctly.  Some drivers will give you a hint about what is wrong.
 If a drive name is not assigned, you probably forgot to include SCSI disk
 support when you built the kernel.</P>

<P>Note the <TT>READ CAPACITY failed</TT>.  Most SCSI drivers (like this one)
 will detect that the drive is a removable media type, and not get all
 flustered when it can't read the partition table.  However, some SCSI cards
 aren't as graceful.  If your PC hangs during boot, try booting with
 a cartridge in the drive.</P>

<P>Check the README files in /usr/src/linux/drivers/scsi and the Kernel
 HOWTO for other debugging hints.</P>


<SECT1>Device Name

<P>In the log output in the previous section note the raw SCSI device name,
 which in this case is "sda", the full name being /dev/sda.  If the Jaz drive
 is the only SCSI disk on your system, it will typically be /dev/sda.  If
 your primary hard drive is SCSI, or you have a SCSI CD-ROM drive, it could
 be sdb, sdc, etc.</P>

<P>Whatever the drive name is, you will need this name to access the drive,
 as explained in later sections.</P>


<SECT>Using a Jaz Disk

<SECT1>DOS Formatted Disks

<P>Jaz disks come pre-formatted from Iomega with a single partition using
 the DOS FAT16 file system.  The single partition is usually the 4th disk
 partition (for Mac compatibility - the Mac requires data to be on the 4th
 partition, but the PC doesn't care which partition data is on).</P>

<P>Linux is perfectly happy reading and writing a FAT16 file system, so you
 can use the disk as is.  In order to use the disk, you need to mount it, so
 the first thing you need to do is create a mount point.  For this document,
 we'll mount all our DOS Jaz drives under <TT>/dos_jaz</TT>, so let's create
 that mount point (you'll need to be root for most of this stuff).  You'll
 only need to do this once:</P>

<P><TT>mkdir /dos_jaz</TT></P>

<P>In a previous section, I mentioned you'd need to remember the Jaz drive's
 raw SCSI device name.  You need that now.  If your drive is
 <TT>/dev/sda</TT> then all these examples will work for you.  If not, you'll
 need to replace "sda" with the device ID of your Jaz drive.  Since you need
 to issue these commands as root, you'll want to be sure you have the correct
 names.</P>

<P>If you have a 2.0 kernel, or have added VFAT support, you can mount the
 Jaz disk this way, and have long filenames under FAT16:

<P><TT>mount -t vfat /dev/sda4 /dos_jaz</TT></P>

<P>Note that although VFAT allows you to use long filenames, those filenames
 are still case <EM>in</EM>-sensitive, and although 'ls' lists permissions,
 you can't actually change permissions on any of the files.</P>

<P>If the "vfat" format is not recognized by the mount command, then you'll
 use this command to mount the Jaz disk:</P>

<P><TT>mount -t msdos /dev/sda4 /dos_jaz</TT></P>

<P>Once you have issued either of the mount commands, files from the disk
 will appear under the <TT>/dos_jaz</TT> directory.  While the disk is
 mounted, you will not be able to eject it.</P>

<P>When you are done with the disk, you can unmount it with the command:</P>

<P><TT>umount /dos_jaz</TT></P>

<P>Once unmounted, you can press the button on the front of the drive to
 eject the cartridge.</P>

<SECT1>Repartitioned DOS Jaz Disks

<P>Since a Jaz disk is simply a disk, it can be repartitioned and reformatted
 like a fixed disk.  If this is done, you need to know which partition numbers
 were used during repartitioning to be able to mount the disk.</P>

<P>For instance, if the partition table was wiped, and a single new partition
 was created as the first partition, the two mount commands from the previous
 section would be:</P>

<P><TT>mount -t vfat /dev/sda1 /dos_jaz</TT></P>

<P>and</P>

<P><TT>mount -t msdos /dev/sda1 /dos_jaz</TT></P>


<SECT1>Linux-Native Jaz Disks

<P>Linux-Native Jaz disks allow files to be stored with standard Unix
 permissions and case-sensitive filenames.  The only drawback to Linux-Native
 disks is that they can no longer be used on DOS/Windows machines.</P>

<P>A Jaz disk looks the same as a hard drive to Linux, so for those of you
 familiar with the Linux disk management tools, none of the following will be
 a surprise.

<P>If you want to erase a Jaz disk and make a Linux native file system on
 it, you use fdisk on the entire disk.  Please be very careful using fdisk,
 especially if you have a SCSI hard drive - we wouldn't want to have any
 "accidents".  :-)  In particular, make sure you are operating on the correct
 device before making changes.  In most cases, you'll use:</P>

<P><TT>fdisk /dev/sda</TT></P>

<P>and delete the existing partitions (with the d command).  Then create a new
 partition with the n command, make it primary partition number 1 (using all
 the cylinders), use w to write the partition table to disk, and quit with
 q.</P>

<P>Once the partition has been created, format it with:</P>

<P><TT>mke2fs /dev/sda1</TT></P>

<P>(The 1 is the number that you gave this partition in fdisk).  I prefer to
 create a separate mount point for Linux native Jaz disks, and you'll see why
 a little later when we talk about the <TT>fstab</TT>. So let's create that
 mount point now, and then mount the disk:</P>

<P><TT>mkdir /jaz</TT></P>
<P><TT>mount -t ext2 /dev/sda1 /jaz</TT></P>

<P>As usual, when the Jaz disk is mounted, it cannot be ejected.  When you're
 done using the Jaz disk, you unmount it with:</P>

<P><TT>umount /jaz</TT></P>

<P>Once unmounted, you can press the button on the front of the drive to
 eject the cartridge.</P>


<SECT1>Checking Linux-Native Jaz Disks

<P>Like your other disk drives, once a Linux Jaz disk has been mounted and
 unmounted a certain number of times, the system will mark the disk as
 "dirty".  When this happens, you'll get a message like:</P>

<P><TT>Mounting unchecked filesystem, /dev/sda1.  Recommend running e2fsck.</TT></P>

<P>Once you see this message, it's a good idea to go ahead and check the disk.
 The disk must be <EM>unmounted</EM> in order to check it.  Unfortunately, you
 only get the "dirty" message when you mount it, so you can either check the
 disk when you're done using it, or unmount it, check it, then re-mount it.
 Use the following command to check the disk (assuming the partition to be
 checked is the first one):</P>

<P><TT>e2fsck /dev/sda1</TT></P>


<SECT1>Using the fstab to Make Things Easier

<P>Up to now, we've had to be root to mount and unmount the Jaz disks, and
 we've had to type quite a bit to mount the Jaz disks.  By adding a couple of
 entries to the file <TT>/etc/fstab</TT>, we can make using the Jaz drive
 <EM>much</EM> easier.</P>

<SECT2>DOS Format Disks

<P>If you've got preformatted DOS disks, and you've created the
 <TT>/dos_jaz</TT> mount point, you can add this line to the file
 <TT>/etc/fstab</TT>:</P>

<P><TT>/dev/sda4 /dos_jaz vfat defaults,user,nosuid,noauto 0 0</TT></P>

<P>With this line in the fstab, <EM>any user</EM> can mount and unmount a
 DOS-format Jaz cartridge with the following commands:</P>

<P><TT>mount /dos_jaz</TT></P>
<P><TT>umount /dos_jaz</TT></P>

<P>This is because we have told Linux what the Jaz device ID and media type
 are in the <TT>fstab</TT>, plus we have given the <TT>user</TT> option to
 allow any user to mount and unmount the disk.  Naturally, if your Jaz drive
 is other than <TT>sda</TT>, you'll need to change that, and this won't work
 for DOS cartridges that have been repartitioned without another entry in
 the fstab that uses a <EM>separate</EM> mount point (e.g. /dos_jaz2).</P>


<SECT2>Linux Format Disks

<P>If you've got Linux formatted disks, and you've created the
 <TT>/jaz</TT> mount point, you can add this line to the <TT>fstab</TT>:</P>

<P><TT>/dev/sda1 /jaz ext2 defaults,user,exec,nosuid,noauto 0 0</TT></P>

<P>With this line in the fstab, <EM>any user</EM> can mount and unmount a
 Linux-format Jaz cartridge with the following commands:</P>

<P><TT>mount /jaz</TT></P>
<P><TT>umount /jaz</TT></P>

<P>Once again, we have told Linux what the Jaz device ID and media type are
 in the <TT>fstab</TT>, plus we have given the <TT>user</TT> option to allow
 any user to mount and unmount the disk.  Some system administrators may not
 wish to have the <TT>exec</TT> option present, as there are some security
 risks with letting any user run an executable of unknown origin from the
 drive, but with the <TT>nosuid</TT> option present, these risks are
 minimal.</P>


<SECT2>Automatic Mount at Boot Time

<P>Both of the <TT>fstab</TT> examples above have the option <TT>noauto</TT>
 in them to prevent the disk from being automatically mounted at boot time.
 In general, this is a good idea because if there is no disk in the drive
 when the computer boots, or the drive is powered off, it can cause varying
 amounts of trouble, depending on which SCSI driver you are using.</P>

<P>If you're <EM>sure</EM> you want to mount the jaz drive at boot time,
 simply remove the <TT>noauto</TT> option, and make sure the drive is on,
 and a cartridge is inserted before booting.  Note that you can only have
 one fstab entry for jaz drive that will auto-mount, or you may encounter
 the same problems as if there was no cartridge in the drive.</P>


<SECT1>The Jaz "tools" Disk

<P>With some Jaz drives, the software to run the drive is supplied on a
 Jaz cartridge instead of on CD-ROM.  The "problem" with these disks is that
 software-controlled write protection is enabled on the disk, so that the user
 can't wipe the disk until after the tools are installed at least once.</P>

<P>There are several ways you can reclaim the Jaz tools disk:
<ITEMIZE>
 <ITEM>Install the tools on a DOS/Windows computer.
 <ITEM>Use a DOS/Windows computer with the Jaz tools already installed to
   remove the password protection.
 <ITEM>Use one of the Linux Utilities mentioned in a later section to remove
   the password protection.
</ITEMIZE></P>

<P>If you have access to one of the password protection removal programs, all
 you need is the password that Iomega uses, and it is:</P>

<P><TT>APlaceForYourStuff</TT></P>

<P>Note that capitalization is important.</P>


<SECT>Linux Utilities for Jaz Drives

<SECT1>jaztool

<P>jaztool is a Linux utility written by Bob Willmot to support some of
 the Jaz drive's features (including software controlled ejection and write
 protection).  I like jaztool because its commands can be embedded in alias
 commands and scripts.  It's also easy to compile and install.</P>

<P>The original source code for jaztool can be found at
 <url url="http://www.willmot.com/jaztool/" name="http://www.willmot.com/jaztool/"> and is also mirrored at my site at
 <url url="http://www.ultranet.com/~hsd/HOWTO/index.shtml#jaztool" name="http://www.ultranet.com/~hsd/HOWTO/index.shtml#jaztool">
 </P>

<P>Note that to use jaztool with a 2Gb Jaz drive, you must change ONE line
 of code.  Change line 188 from this:</P>

<P><TT>return(!strncasecmp(id,"IOMEGA  JAZ 1GB",15));</TT></P>
<P>to this:</P>
<P><TT>return(!strncasecmp(id,"IOMEGA  JAZ",11));</TT></P>

<P><BF>NOTE:</BF> There are <BF>two spaces</BF> between IOMEGA and JAZ in
 the previous two lines of code.  SGML (or maybe just HTML) apparently
 removes the extra whitespace.</P>

<P>After building jaztool and installing it, it must be suid root, or run
 as root, or it won't work.</P>

<P>I use jaztool regularly, so if you have a question about it, I would be
 happy to try and answer it.</P>


<SECT2>Ejecting a Cartridge

<P>Use the following command to eject a cartridge:</P>

<P><TT>jaztool /dev/sda eject</TT></P>

<P>This might seem like a lot to type, but it's easy to make a slick
 alias like this:</P>

<P><TT>alias jazej 'umount /jaz; jaztool /dev/sda eject'</TT></P>


<SECT2>Password Protection

<P>There are two password protection modes on a Jaz, and both are controlled
 through software.  One is Write Protected and the other is Read/Write 
 Protected.  jaztool will allow you to unlock a Write Protected disk, but
 under Linux, a device that cannot be read cannot be mounted, so Read/Write
 Protected is not supported.</P>

<P>If the cartridge is Write Protected (such as a Jaz Tools disk), use the
 following command to unlock it (the disk must not be mounted):</P>

<P><TT>jaztool /dev/sda rw</TT></P>

<P>jaztool prompts for a password, and if the password is correct, the disk
 is unlocked and ejected.  This must be done to cause the SCSI driver to
 pick up the new mode when the cartridge is re-inserted.</P>

<P>To make the disk Write Protected again, use the following command:</P>

<P><TT>jaztool /dev/sda ro</TT></P>

<P>jaztool again prompts for a password, and the disk is locked and 
 ejected.</P>

<P>Note that jaztool doesn't support the "Unprotect until Eject" feature
 found in the Windows world.  If you remove the password protection, it
 is removed until you put it back on.</P>


<SECT1>jaZip

<P>If you'd prefer a nice, slick, graphical user interface to control
 your Jaz (and Zip!) drive, there's the jaZip tool.  Check it out at:
 <url url="http://www.scripps.edu/~jsmith/jazip/" name="http://www.scripps.edu/~jsmith/jazip/">
 </P>

<P>I haven't used jaZip myself, so please contact the author directly with
 questions on jaZip.  Contact information is on the website listed above.</P>


<SECT>Booting from a Jaz Cartridge

<SECT1>BIOS Issues

<P>If the Jaz drive co-exists with other SCSI harddrives, most BIOSes will
 want to boot the disk that has the lowest SCSI Id.  The Jaz drive can be
 set to SCSI Ids 0-6, and typically come out of the box set to SCSI Id 5.
 Some BIOSes detect and skip removable devices like the Jaz.  If your
 BIOS will boot from a Jaz, you can set your main SCSI harddrive to SCSI
 Id 1, then you can change the Jaz from SCSI Id 5 to 0 when you want to
 boot from the Jaz.</P>

<P>More typically, the Jaz drive co-exists with an IDE harddrive.  Nearly
 every BIOS will want to boot the first IDE harddrive.  Some BIOSes will
 allow you change a setting in the BIOS setup to boot from a SCSI device
 first.  Others may require you to disable the IDE drives in the BIOS
 setup.  Still others may require detaching the IDE drives physically or
 disabling the IDE interface.</P>


<SECT1>Installing Linux on a Jaz Cartridge

<P>Although running Linux from a Jaz cartridge is <EM>much</EM> slower than
 running from a harddrive, the Jaz drive makes an excellent ERD (Emergency
 Repair Disk).  It's also fun to be able to just pop in some new Linux system
 or to try Linux on someone else's Jaz-equipped machine.</P>

<P>By far the easiest way to install Linux on the Jaz cartridge is simply to
 follow the install procedure for your favorite distribution with the Jaz
 drive being the only drive on the system.  I've done this with RedHat 5.2,
 and it works perfectly.  If you're not completely comfortable with doing
 weird, wild stuff with LILO, it's the only way to go.</P>

<P>If you want to do an "install" from your running system, you can
 often succeed in "building" a bootable system on a Jaz cartridge.</P>

<P><ITEMIZE>
 <ITEM>Partition the drive and make the filesystems.  You probably need to
  have a swap partition, too, but if you have lots of RAM then maybe not.
  Mount the new root as /jaz and any additional partitions within that
  directory as appropriate.
 <ITEM>Copy all the files into place.  Be sure all the <TT>/dev</TT>
  files are copied.  Be sure all permissions, ownership and group ids
  are retained.
 <ITEM>Modify the files on the Jaz cartridge to suit the
  circumstances of booting from it.  In particular be sure to change
  <TT>/jaz/etc/fstab</TT> to mount the Jaz cartridge partition(s) as
  appropriate.  Also change <TT>/jaz/etc/lilo.conf</TT> to match as well.
 <ITEM>There are two alternatives for installing the LILO boot loader:
 <ITEMIZE>
   <ITEM>Make a kernel image floppy and use <TT>rdev</TT> to make it
    mount the Jaz cartridge as root.  Boot from the floppy when ready
    the first time then run LILO to make the Jaz MBR bootable.
   <ITEM>You can run LILO from your non-Jaz root running system to
    install the bootable MBR on the Jaz cartridge.  For more information
    on this option, check out <url url="http://metalab.unc.edu/mdw/HOWTO/mini/LILO.html" name="Alessandro Rubini's LILO mini-HOWTO">
 </ITEMIZE>
</ITEMIZE></P>

</ARTICLE>
