Adding a 5th SCSI-disk on SCO Enterprise System 3.0

Adding a 5th SCSI-disk on SCO Enterprise System 3.0

Post by Bjorn Lin » Tue, 20 Feb 1996 04:00:00

I have tried to add a 5th SCSI disk on SCO Enterprise System Release 3.0 with no
success. This was on a HP Netserver LM/66 which has Adaptec 2740 Twin Channel
SCSI-adapter.The server boots from the SCSI-disk with ID:0. When mkdev hd is ran the second time (after having rebuild and installed a new kernel) the following happen as fdisk is invoked:
        WARNING: Poll command failed on drive ID:4
        cannot open /dev/rdsk/4s0
My first guess was that something was wrong with the SCSI-disk. Not so. I have
tried a another disk and a wormunit, changed IDs on both with the same result.

Next I found that the /dev-directory contained no nodes for a fifth disk.I looked into /etc/conf/node.d/hd and found that file had no entries
for a 5th disk. Maybe the allocation of  virtual major numbers was faulting?
Dosn't seem so. A closer look on /etc/conf/cf.d/mdevice shows two hd entries:
hd      hoc      irobCcGk               hd      1       1       1       1       -1
hd      hoc     iobCcGkM                hd      80      80      1       256     -1

My belief was that /etc/conf/node.d/hd should have entries for the 5th refered to with minor numbers from 256 and above and that idmknod was to make these devicenodes during installation of the new kernel.

Am I trying to the impossible or is there a missing link?

Bj?rn Lind
Alcatel Telecom Norway
Message Handling Systems


Adding a 5th SCSI-disk on SCO Enterprise System 3.0

Post by Lucky Leavel » Tue, 20 Feb 1996 04:00:00

Check the value of NDISK.  On OSE 3.0, it defaulted to 4, which may well
explain why the fifth hd causes problems. (On OSR5 it is 0 which means
the OS adjusts it dyanmically, or, it is no longer a factor.)

Also, check the value of NMOUNT, the number of mounted filesystems.

Hope this helps,

Lucky Leavell                            Phone: (812) 945-6555
Relational Information Systems, Inc.       FAX: (812) 949-9233

New Albany, IN 47150-2013                       71534,2674 (CompuServe)
WWW Home Page:


Adding a 5th SCSI-disk on SCO Enterprise System 3.0

Post by Bjorn Lin » Thu, 22 Feb 1996 04:00:00

Sorry I forgot to mention the value of NDISK, but it is 8, and NMOUNT is 29. So there seems to be something else.

Bj?rn Lindi
Alcatel Telecom Norway


1. Can one add IDE disks after SCSI disks on Free SCO?


I intend to "buy" a Free-SCO, but I would like to know if I can add IDE
disk drivers after SCSI disks. This is not possible in 3.2v4.0.

As I have two 1G IDE and one 1G SCSI, I was thinking in setting up the
SCSI disk as the installation one and later add the IDE ones.

Also, I am using the Triones device drivers that come with my
motherboard end emulate a SCSI disk from an EIDE one. Could I use them
in v5.002? Are they worth?

The boot message in v4.0:



R. Jose Falcao 110   |  tel:    + 351 2 2094345
4000 Porto, Portugal |  fax:    + 351 2 2008487

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