[comp.sys.att] Adding another hard-drive to a 3B2

ibarra@DPW.COM (Michael Ibarra) (05/03/91)

I have attempted with no luck to answer someones (Steve Gaardner) mail for
help on adding another hard drive to a 3B2/310. Here is what I did to add another drive to my 3B2/300. I hope this helps you...



 ** Most of these notes are from conversations with Orlan Cannon vmp!oc **

	       Cable description for below instructions.

You should have a Y-cable to split the power supply cable now going into
your existing hard drive to accomodate *two* hard drives, I believed I used
a female to two males cable.

You need a 20-socket to 20-edge ribbon cable for the additional drive.

You need a 37-socket to 37-edge to 37-edge ribbon cable. This looks something
like this:


			    37-edge: to drive
 37-socket: to motherboard         unit#0          37-edge: to drive unit#1
	    |_|______________________|_|_________________________|_|

You will see the difference between the edge connector end and the pin
connector end. I made my cable 2 1/2 feet from the pin connector to the
first edge connector then another 2 1/2 feet to the end of this ribbon
cable to the other edge connector. I made my 20-pin to 20-edge ribbon cable
approximately 3 feet. I made the cables this long because I located the
second drive outside of the cabinet of the 3B2 (temporarily, I plan to
put it all inside of a tower case real soon).


		ADDING A SECOND HARD DRIVE ON THE 3B2

1-   Back up the entire existing hard drive.

2-   Powerdown the machine, unplug and with an antistatic wristband, remove
     the existing hard drive and replace it with what will be the second
     hard drive to this system.

3-   Power on the machine and since this drive has no operating system yet,
     you should go into fimware mode. At this point you should have a
     floppy with idtools or equivalent. Using the 'formhard' command in
     idtools, format the hard drive with a verify (I did this two times
     just to be sure).

4-   Now you have to powerdown the system again and using the same
     antistatic precautions above, remove the hard drive from this system.
     The cabling part now comes into play. The power cord that was going
     into your hard drive now has to be plugged in to the Y-cable(power)
     above. This cable then gets each of its two ends plugged in to one
     of each drive for this system (its OK, the power supply can handle
     the extra load!). There is a narrow cable comming off of the
     motherboard onto where the original drive was, on the motherboard
     where this comes off of is another connector that is empty. Here
     place the 20-pin cable specified above (this cable is the control
     cable). Next, replace the wide 37-pin cable with the one one described
     above. Run these two cables beneath the motherboard and away from
     the power cables for either of the two drives or the power cable
     for the motherboard. By the way, I placed a piece of cardboard
     beneath the motherboard to prevent contact with the control (20-pin)
     cables and the data (37-pin) cable. You should now have two 20-pin
     cables, one for each tape drive and one 37-pin cable for the data
     of *both* of the tape drives.

4-   Now, depending upon how you are going to set up your system (which
     drive becomes unit 0 and which unit 1). If the original drive is to
     become the first drive on this chain then make sure the address
     with the jumpers on the drive itself are set to unit 0. The second
     drive of this chain will become unit 1, make sure that this one is
     addressed as unit 1 with the jumpers on the drive itself. remove the
     terminating resistor on the drive that is unit 0. Make sure that you
     have one on the drive that is to become unit 1 on the chain.

5-   Connect all of the drives according to their proper places on the
     chain. The existing 20-pin cable goes to the 20-pin edge connector
     on the unit 0 drive, and the one 20-pin connector that was added to
     the motherboard goes to the 20-pin edge connector on the *additional*
     second hard drive. What should be remaining is the use of the 37-pin
     cable. Connect the 37-pin edge connnector that is in the middle of
     this ribbon cable to the drive that is unit 0. Connect the other end
     to the additional hard drive that is addressed as unit 1 on the
     chain. Again make sure that *ALL* of the cables are secure and pin one
     on the connector goes to pin one on the drive for *ALL* of the cables
     that's 20-pin and 37-pin.

       STEP SIX ONLY IF YOU ARE USING THE DRIVE THAT WAS THE EXISTING
		       ORIGINAL AS UNIT 1.
	   (when done or if not necessary skip to step 7)


6-   Power up your machine and using idtools do a disk to disk (DD) copy
     of the drive unit1 (id2, internal drive #2) to its destination, drive
     unit0 (id1, internal drive #1). When this is done, check to be sure
     that it worked by attempting to boot a job off of this drive, you
     should get a message stating these are the only files found on this
     drive. Now format the second drive on this chain and verify it too
     using formhard. (you may have to add the bad block data by hand, if so
     then format it again maybe twice with a verify after you have entered
     this information to the drives bad block list.

7-   Run filledt from the idtools diskette. When you are done you should
     go back into firmware mode and after typing in unix as the program
     you wish to execute, you should see ALL of the drives on the system
     as valid choices (FD5, HDXX & HDXX). Type in the first hard drive,
     which by now should have the contents of the original hard drive on
     it. Upon reboot, you are going to receive a message saying BAD SANITY
     WORD IN VTOC DRIVE #2. This is OK since you have not yet mounted this
     drive on the system. Using the sysadm partitioning portion of sysadm,
     you should then partition and mount the second hard drive. Now you
     should have a VTOC (volume table of contents) on the second drive unit
     #1. "Powerdown" the machine and power back on again, you should now
     reboot automatically from the first hard drive and receive no error
     messages regarding the VTOC from the second drive.

			  GOOD LUCK!

If you experience trouble during the disk to disk copy, then since you
already backed up your original drive with all of your precious data, just
do a operating system core set reload, then using the sysadm or whatever
backup utility you like do a reload from your disks.


			 Mike Ibarra
		      ibarra@esquire.com