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MO Drives (O2 Compatible)

From Higher Intellect Vintage Wiki

The following Magneto-Optical (MO) drives are known to work with the O2:

  • Fujitsu MCM3064SS
  • Fujitsu MCM3130SS
  • Fujitsu MCJ3230SS

Magneto-Optical Tips & FAQ[edit]

Diego De Giorgio (Generatrix) has written the bilingual guide: The MO Drive IRIX FAQ


I'll intend to write a short FAQ about the use of Magneto Optical Drives on IRIX/4Dwm. I'll cover initially only the Fujitsu MCC3064SS drives, but testings with Olympus MOS320E and others will follow soon.

The above Fujitsu model seems to be among the best of bests about reliability, speed, easiness to configure, and more specially, versatility and price/performance relationship.

I'll add more details on next posts, since this is a work in progress, motivated by an ask from one of my customers. Also, I'll try to include details about the undocumented DIP Switch settings for a few special features that I'm actually testing.

The Shortest Path[edit]

Assuming that you already have properly connected and configured your MOD drive to a given SGI system, with a SCSI Controller# (1), SCSI Device ID# (4), and SCSI LUN# (0), just open any command console and do the following:

(1) - Partitioning:

'efs' (...or...) 'xfs'

(2) - Formatting:

'mkfs_efs /dev/rdsk/dks1d4s7'   (EFS Filesystem)


'mkfs_udf /dev/rdsk/dks1d4s7'   (UDF Filesystem)


'mkfs_xfs /dev/rdsk/dks1d4s7'   (XFS Filesystem)

(3) - Adding To The Filesystem Mounting Table:

'nedit /etc/fstab'

(Add One Of The Following Lines)

'/dev/dsk/dks1d4s7 /MOD efs rw 0 0'


'/dev/dsk/dks1d4s7 /MOD udf rw 0 0'


'/dev/dsk/dks1d4s7 /MOD xfs rw 0 0'

(4) - Creating The Mounting Dir:

'mkdir /MOD'

(5) - Mounting The Unit:

'/sbin/mount /dev/dsk/dks1d4s7 /MOD'

(6) - Unmounting The Unit:

'/sbin/umount /dev/dsk/dks1d4s7 /MOD'

(7) - Checking/Fixing The Filesystem:

'fsck /dev/rdsk/dks1d4s7'

(8) - Adding To The 'mediad' Configuration File:

'nedit /etc/config/mediad.config'

(Add The Following Lines)

'# Check A MOD Device For Insertion And Removal
 # Every 60 Seconds
 monitor device /dev/scsi/sc1d4l0 inschk 60 rmvchk 60'

(9) - Starting/Stopping The 'mediad' Daemon:



'/etc/init.d/mediad -f' (Foreground Service And Full Debugging)


'/etc/init.d/mediad -l 7 -a' (Background Service And Full Debugging)

'/etc/init.d/mediad -e /dev/scsi/sc1d4l0' (Media Ejecting)