sudha@herodotus.cs.uiuc.edu (Sudhakar Yerramareddy) (02/28/91)
We recently installed a Fujitsu M2266S disk ( 1.2 GB ) on our VAXstation 3100. We used ns:85 nt:15 nc:1658 and made two partitions (a and g). We filled up about 60% of the 'a' first partition and it seemed o.k. Then we were restoring some files onto the second partition from tape. When this partition was about 2/3 full, we lost the '.' directory from our first (a) partition. We believe that something from the second partition wrote over that. We called Fujitsu and Clayton (the vendor) and they suggested that nc be reduced to 1644. We remade the file systems, and we had the exact same problem. If anyone can tell what the problem seems to be based on the symptoms and on their experience with this disk, we would really appreciate it. If any one has used this disk, please let us know the correct parameters to use, etc. Thanks. -- sudhakar (for KBESRL, U. of Iillinois at U-C)
grunwald@foobar.colorado.edu (Dirk Grunwald) (02/28/91)
in general, here's how to hook a SCSI disk up to an Ultrix machine. use rzdisk -g current, record the total number of blocks available. Invoke mathematica, and use FactorInteger ot determine prime factors of the number of blocks. Choose a reasonable number of sectors per track from the prime factors. Choose a reasonable number of heads from the prime factors. Divide through and get the number of cylinders. Bingo, you now have a maximal geometry for your drive. Subtract some cylinders for UNIX, which still thinks it needs to remap things (the drive actually handles this), throw the information at a SC/VC spreadsheet and partition away. The interface to SCSI drives has no concept of 'cylinders', 'tracks' or 'heads'. Most drives record a variable number of sectors per tracks anyway. The UNIX utilities have not kept pace with these drives. Also, don't forget to enable the cache read ahead on the FUJI drives. It's a noisy drive, but fast. Dirk Grunwald -- Univ. of Colorado at Boulder (grunwald@foobar.colorado.edu) (grunwald@cs.colorado.edu)