RAIT

Last Thursday, 10-Feb-2011 14:58:47 JST

What's rait

Redundant Arrays of Inexpensive Tapes.
rait likes RAID (Redundant Arrays of Inexpensive Disks)
Fast backup, rait stores multi tape drives.(maybe !?)
backup tape Security, if each tape managed by other places/managers.(?)

Source Latest Version

rait-0.3.tar.Z ---- Dec 12 1999
rait-0.2.tar.Z ---- Dec 3 1999
rait-0.1a.tar.Z ---- Dec 3 1999
rait-0.1.tar.Z ---- Dec 2 1999

RAIT Performance

Performance Graph

Test Environment information.

FreeBSD 2.2.8-RELEASE #0: Sun Dec  5 10:58:59 JST 1999
    root@?????:/usr/src/sys/compile/?????
CPU: Pentium II (quarter-micron) (334.09-MHz 686-class CPU)
  Origin = "GenuineIntel"  Id = 0x650  Stepping=0
  Features=0x183f9ff,,MMX,>
real memory  = 268435456 (262144K bytes)
avail memory = 260726784 (254616K bytes)
Probing for devices on PCI bus 0:
chip0  rev 2 on pci0:0:0
chip1  rev 2 on pci0:1:0
...
ahc0  rev 0 int a irq 12 on pci0:11:0
ahc0: aic7880 Wide Channel, SCSI Id=7, 16 SCBs
ahc0 waiting for scsi devices to settle
...
(ahc0:5:0): "HP C1533A A612" type 1 removable SCSI 2
st0(ahc0:5:0): Sequential-Access density code 0x13, variable blocks, write-enabled
ahc0:A:6: refuses WIDE negotiation.  Using 8bit transfers

ahc1  rev 0 int a irq 11 on pci0:12:0
ahc1: aic7880 Wide Channel, SCSI Id=7, 16 SCBs
ahc1 waiting for scsi devices to settle
...
ahc1:A:4: refuses WIDE negotiation.  Using 8bit transfers
(ahc1:4:0): "ARCHIVE Python 28388-XXX 5.91" type 1 removable SCSI 2
st1(ahc1:4:0): Sequential-Access density code 0x13, 512-byte blocks, write-enabled


% mt -f /dev/rst0 status
Present Mode:   Density = X3B5/88-185A Blocksize variable Comp 0
---------available modes---------
Mode 0:         Density = 0x00         Blocksize variable
Mode 1:         Density = X3.136-1986  Blocksize = 512 bytes
Mode 2:         Density = X3.39-1986   Blocksize variable
Mode 3:         Density = X3.54-1986   Blocksize variable
% mt -f /dev/rst1 status
Present Mode:   Density = X3B5/88-185A Blocksize variable Comp 0
---------available modes---------
Mode 0:         Density = 0x00         Blocksize variable
Mode 1:         Density = X3.136-1986  Blocksize = 512 bytes
Mode 2:         Density = X3.39-1986   Blocksize variable
Mode 3:         Density = X3.54-1986   Blocksize variable

Running Sample DATA

Changes

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