Sun Tape Drives

We have two Exabyte 8mm tape drives and three 4mm DAT drives. Both types of drive write, by default, in native(uncompressed) mode. Tape media for both types of drive come in different lengths. The drives will read media written by older model drives at lower densities.

We also have a special purpose SDLT drive. This drive writes by default in compressed mode. It writes only to SDLT tape media. It can read media written by other model SDLT and DLT drives.

The 4mm DAT drives(on attila & pirates) can write up to ~24GB per tape using compressed mode and a DDS-3 125m tape. The newer 4mm DAT drive(on hoffman) can write up to ~40GB per tape using compressed mode and a DDS-4 150m tape. All the 8mm drives write 5GB per 112m tape uncompressed(10GB compressed) and a maximum of 14GB using compressed mode and a 160m tape.

Locationhost|device namedevice type (max storage)
1008pirates/dev/rmt/04mm, DDS-3 (24GB)
1008pirates/dev/rmt/1SDLT (320GB)
1328isolde/dev/rmt/08mm (14GB)
1328isolde/dev/rmt/14mm, DDS-3 (24GB)
1004hoffman*/dev/rmt/04mm, DDS-4 (40GB)

Solaris tape drive device names(1st tape device is usually 0):

/dev/rmt/0	(default density, usually uncompressed)
/dev/rmt/0l	(low, same as uncompressed)
/dev/rmt/0n	(norewind)
/dev/rmt/0c	(compressed)
/dev/rmt/0h	(high, same as compressed)
/dev/rmt/0cn	(compressed, norewind)
		(/dev/rmt/0nc is NOGOOD)

Density note

Drive senses density of a tape it is reading. When writing a tape, you select the density when you specify the device name.

On the (10-14GB) exabyte drives, when the drive is active: the flashing middle LED light is amber if drive is in high density mode but is green if drive is in low density mode.

Tape I/O errors on read

A likely cause if all seems okay otherwise: a large block size used when tape was written.

Way around error:

TAR

tar tfb /dev/rmt/0 100 
(asks for buffer(b) size of 100. Default max buffer size is 20)

UFSRESTORE

ufsrestore -ibf 252 /dev/rmt/0	
(asks for buffer(b) size of 252. can try larger numbers as well)