Can't see scsi drive

Where OS 9 did backflips to give you a break on SCSI, Mac OS X does the reverse.

The SCSI Bus must be terminated. The convention for internal 50-pin (narrow) drives was to set the Termination Enable strap on the last drive. The convention for external 50-pin drives was to use an external terminator applied to the second connector on the drive.

At least one device on the Bus must provide power to run the Terminators. Many Hard Drives can be strapped to provide that power, but cheaper devices like scanners, printers, and Zip drives may not be able to provide it.

Each SCSI device must have a unique ID setting.

External cables must be grounded, shielded cables intended for SCSI drives, not just any-old-cable such as a spare RSS-232 cable. In certain cases, the cable length is restricted.

Which SCSI card is this, and what kind of cabling are you using? {internal, external, ribbon, round, 25-pin, 50-pin, 68-pin, 25-to-50 Mac "System" cable, other}

The standard Apple set-up since the beige G3 includes a 3-drive, pale yellow 68-pin cable folded many times so that the connectors line up with the three drive bays. Wide drives were often shipped. This 'N' (for narrow) may be a replacement drive, or it may be suffering from the tighter rules under Mac OS X. If it is on a gray 50-pin cable, it is very likely not original, but can be made to work, if the drive is not dead.

You will need to find the J2 connector and make certain that the TE jumper is in place. It is the jumper farthest from pin 1 on that connector. Unfortunately, it looks from the drawing in the Product Manual like that connector is on the side of the circuit board, usually underneath the drive mounting sled.

The product manual in .pdf form is here, if you have broadband:

http://www.seagate.com/support/disc/manuals/scsi/32661d.pdf

page 37 of about 90 has the J2 diagram for the 'N' model drives.

From verbal descriptions on page 40, you also need to have at least one jumper on TP2 (or between the outboard positions of both TP1 and TP2 refrerenced as "A".)

TP2 TP1 (Does not apply to “WC” models)
Off Off No terminator power is connected to drive terminators or SCSI bus I/O cable*.
On Off Drive supplies its own terminator power only. Jumper on this position is factory default.
Off On Drive supplies power to SCSI bus I/O cable*; none to internal terminators.
On On Drive supplies terminator power to itself (internal connection) and to SCSI bus I/O cable*.
..........*This is a legal jumper setting.

TP1 and TP2
“Position A” (Applies only to “N” and “W” models)
On This horizontally positioned jumper across the two TP positions furthest from the PCB edge,
......connects terminator power from SCSI bus I/O Termpower cable* to the
......drive’s internal terminators (for single-ended I/O only).
Off See above explanations for TP jumpers.

It sounds like you have the jumpers set to provide proper Termination.

If I go into the scsi bus it shows the drive

Is that in Apple System Profiler in 10.3?

how to mount it as an accessible drive?

Run Disk Utility. (It should be in the Utilities folder inside the Applications folder). The drive should show up in the list on the left-hand side. Select it and read the info at the bottom and in the large right pane.

That is not good news. The drive may have died.
In Apple System Profiler, does it report the correct drive CAPACITY?
What Target/Identifier is it assigned to?

To get it to mount, you talk to the drive with Disk Utility, and either check it out with "Repair", or write stuff that lives outside the normal file system using "Initialize' or "Erase".

If it is not seen in Disk Utility, it is not working well enough to be repaired or initialized.

Can you run OS 9 on your Mac? There are a few more utilities that can give you more information about the state of your drive.

Do either of those indicate SIZE/Capacity? A size/capacity of Zero indicates your drive has errors (and no more spare blocks) or has a data error in the crucial private areas used by the drive firmware for its own use, or has another Hardware problem.

An OS 9 utility called "Mt. Everything" can sometimes give you more insight as to why it will not cooperate:

http://www.versiontracker.com/dyn/moreinfo/macos/3043

A status of "Not Ready" from that program is usually an indication that the drive itself is no longer functioning. That it did NOT indicate a whole raft of other symptoms pretty much implicates the drive itself, not any other parts of your SCSI setup.

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There are two versions of the Blue & White G3, rev 1 and 2. If you have a Rev 1, Some ATA drives on the built-in Bus can be flaky, and use of an add-on Drive controller like the SCSI controller you have are advised, especially when attempting to use drives faster than the originals or larger than about 40 GB. The litmus test for which revision you have is in this article, section 3. Revised IDE Controller Chip:

http://www.xlr8yourmac.com/G3-ZONE/yosemite/newfeatures.html