5. Linux Utilities for Jaz Drives

5.1 jaztool

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.

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

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

return(!strncasecmp(id,"IOMEGA JAZ 1GB",15));

to this:

return(!strncasecmp(id,"IOMEGA JAZ",11));

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

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

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

Ejecting a Cartridge

Use the following command to eject a cartridge:

jaztool /dev/sda eject

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

alias jazej 'umount /jaz; jaztool /dev/sda eject'

Password Protection

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.

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):

jaztool /dev/sda rw

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.

To make the disk Write Protected again, use the following command:

jaztool /dev/sda ro

jaztool again prompts for a password, and the disk is locked and ejected.

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.

5.2 jaZip

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: http://www.scripps.edu/~jsmith/jazip/

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