A.P. Lawrence

Unixware 7 Tapes

Tapes are in /dev/rmt. A man 7 tape should get you acquainted with these names, or look in /dev/rmt.

Unlike Openserver, you don't specifically add SCSI tapes. If the tape is out there (controller configured, of course), it will automagically get added to the kernel.

If Arcserve is installed

as_devmgr -deviceinfo 2
as_devmgr -tapeinfo 2

would give you information about a SCSI tape at id 2.

Unfortunately, the standard commands (tape and mt) don't support "status", or indeed anything beyond reten,erase,rewind,reset and rfm for tape and only rewind and fsf for mt! The man page for sdi shows that the tape driver supports more than these; the problem is mostly in the commands, not the driver. The tapecntl command implements all of the possible functions, but still lacks (apparently because of lack of support in the driver) the very useful Openserver tape status equivalent. It's fortunate that Arcserve Lite is included with UW7, because the as_devmgr commands are apparently the only way to get useful information from the tape drive.

If your tape shows up in the above commands, but won't work with tar or cpio (just hangs when you try to access it), it is because Arcserve has claimed the device for it's own. If Arcserve is what you intend to use for backups, that's great. Otherwise, you'll need to disable it, temporarily or permanently.

To disable it permanently, you'll need to remove or edit (by adding an exit 0 at the beginning of the file) the /etc/rc2.d/S69ARCserve. To stop the server temporarily (for example, because you want to do a simple cpio backup or restore) use astop. It shouldn't be a big surprise to learn that astart will start it up again.

You can also edit /usr/lib/ARCserve/tapesvr.cfg and remove the semicolon before NO_DEVICE_LOCKING - doing this lets ARCserve run but prevents it from taking control of the tape.

Note that the /dev/rmt files are all rw-rw-rw. This is true in Openserver also, and could represent a security risk as ordinary users could access the device. Arcserve does protect against that if it is running, because it has its own ideas of who is authorized to use its commands.

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