Sequential Mode; Random Access Mode - Sun Microsystems SPARCstorage Library Installation And User Manual

Sequential Mode

Sequential mode allows the tape cartridges to be accessed serially. This is the
most advanced mode supported by the Sun operating system without use of
Networker/Solstice Backup or similar application. When a tape is ejected from
the drive the next tape in the magazine is placed in the drive. In a two drive
library, one half of the tapes in the magazine are used in one drive and one half
in the other drive. This effectively creates a unit that appears like one very long
tape. This is useful for simple backup and restore operations such as ufsdump.
1. To automatically load the first tape into the drive, use the Operator Panel
to select the Restart option.
Restart 1 loads the tape into the first drive. Restart 2 loads into the second
drive.
2. To enable the unit to move to the next tape after ejecting a tape, use the
Operator Panel to select one of the sequential modes.
• Sequential 1 for the first drive.
• Sequential 2 for second drive.
• Dual Sequential for use of two drives simultaneously. One half the
magazine is used with the first drive; the second half is used with the
second drive.
3. To enable the unit to eject a tape from the drive, use :
• mt -f /dev/rmt/x offline [replace 'x' with the drive number] or
• use the l flag with ufsdump.
Access to the on-line man(ual) page is via man ufsdump.
4. To load the first tape after ejecting the last, use the front panel controls to
select the Loop option.
There is both a loop 1 for the first drive and a loop 2 for the second drive.

Random Access Mode

The random access method allows access to any tape in the library. Sun does
not provide a driver in the standard OS to provide this functionality. A random
access driver and a full backup application utility is offered in the Solstice
Backup program. This is a version of the the Legato Networker utility. This
Operating the SPARCstorage Library
3
3-13