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syzygy

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External SCSI cdrom on Sun system

I'm currently trying to get an external cdrom working on a
Sun Sparcstation 10.  the system recognises that the device
is there (probe-scsi can see it and there are c0t6d0sX entries in /dev/dsk/ and /dev/rdsk/ but I'm not sure what the proper command to access the CDrom is.  the system is running Solaris 2.4 at the moment (one of the reasons for needing the CDR to work is so the system can be wiped an upgraded)and it has 2 internal SCSI drives, with the ID's set to 1 and 3 (the CDROM is ID 6)

Currently there in no scsi terminator on the CDROM (I now there should be, but I dont have one right now)

Once the terminator is connected in, how do I access the CDROM?  If it is with the mount command, what device should be mounted?  
Avatar of bedot
bedot

1° a terminator on line SCSI is necessary to avoid problems of echo on the bus, and also any TOS that is able to destruct SCSI cards
2°when you talk about c0t6d0sX, that means
c0 card 0
t6 tag 6 (number SCSI)
d0 disk 0 (number of lun -> logic unit = in recent systems always 0)
sX section #X  that not works on cdrom

so check in /dev for an entry that seems to c0t6d0, and then mount it where you want
ie: mount /dev/dsk/c0t6d0 /mnt
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ASKER

I'll reject this the leave it open until I get the Terminator and check (should be tomorrow) and then assign the points when it's working.

as an interesting note, an external HDD works fine without the terminator, I was able to mount /dev/dsk/c0t5d0s2 just fine (didn't do any serious data transfer to test)  Also after playing with solaris for a bit, it should automatically mount the cdrom in /cdrom/cdrom0 when volcheck is engaged.  but the cdrom obviously has to be working first  :)



Have you tried.........
boot cdrom
at the ok prompt.
You can then install in the norma way, wiping the drive anyway.
Isthis an upgrade or clean install, you should stillbe
ableto doan upgradeby booting from the cdrom.
Booting from thecdrom is the correct way of doing this on my book.
regards
Some newer drives can auto terminate.

or be set to terminate with a jumper setting.
or are terminated by a switch, Just coz it has 2 SCSI outlets doesn't mean
that it HAS to be terminated, you may want to daisy chain them.
If vold is not running. or.......
Kill vold and
mount -F hsfs -o ro /dev/dsk/c0t6d0s0 /cdrom
to mount a cdrom
cd into /cdrom/cdrom0/s0
sorryfor the amountof posts, these came to me one by one.
hope it all helps, anyway.  :))
Avatar of syzygy

ASKER

thanks all, I havn't yet got the terminator.  Other Sun Peripherals that autoterminate have indicator lights on the back (AUTO TERM HIGH/LOW) but these CDR/HDD don't.  

boot cdrom does not work.  It will be a total reinstall of the OS, not only is it a mess but it is an unlicensed mess..
(we have a license for solaris 2.5.1 but not 2.4)


If the cable between controller and device is short, it might work without a terminator. But you should ALWAYS use a terminator for proper function.

If you have installed the terminator and the SCSI ID is set to 6, 'boot cdrom' should work.
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ASKER

OK, I got the terminator and an extra cable so now it goes from the computer to the CDROM to the external HDD to the termiantor (Honda 50 pin active, took a while to find)

now the system sees all device on probe-scsi, and the external HDD can be mounted.  The read light on teh CDROM comes on briefly when running probe-scsi (but it did that before getting the terminator)


/dev/rdsk/c0t6d0s? cannot be mounted (I tried from s0 to s7) and come up with "not a block device"

from the ok prompt boot cdrom restarts the system, the CDROM reads briefly (It didn't do that before) and then it just sits there. (the solaris 2.5.1 CD is in the drive)


Any ideas where to go from here?


Hi
Did you try a boot -r after attaching the cdrom?
Avatar of Rowan Hawkins
I dont see that you have listed what manufacturer of CD-Drive that you are trying to use. Does the one that your useing Support 512 byte blocks instead of the the default by  other scsi CD drives which use a 1024 byte block.

You mention that the device ID's when you boot, its reading the EPROM tag from the Drive. therefor the drive is there physicaly, but if the sun doesnt have a information on that drive type built in you wouldnt be able to mount it either.

The most complete information can be found on the Sun CD-ROM FAQ located at http://saturn.tlug.org/suncdfaq/

/dev/rdsk/c0t6d0s? cannot be mounted (I tried from s0 to s7) and come up with "not a block  device"

Did you try the command I gave you.
Are you trying to mount a raw device instead of a block device.
/dev/dsk
NOT
/dev/rdsk
regards

Avatar of syzygy

ASKER

The CDROM is actually a SUN CDROM, so it better do 512k blocks.  :)  

and yes, I did the boot -r to reconfigure.


rickyr: whoops, youre right... I used rdsk instaed of dsk.  what is the difference?

There are  2 ways of acessing a  drive, thru the character special or raw device.
and  thru the block device.
Raw devices cannot be mounted and are used for fsck'ing, swap, databases use raw devices for effiency, once  written to the databasecan  be sure that there is no data still being buffered, writes to such a partition are not buffered by the system.

Block devices, are random access (not streamed as with raw devices) and are used to mount  filesystems. This is so you can seek to any area of the filesystem, at any time. Block devices are where you "create" your new filesystems......
newfs /dev/dsk/c0t0d0s#

I don't have the knowledge to makeitanymore technical, hope its enough.

http://www.yggdrasil.com/bible/khg-0.6/khg/node19.html

regards
Did it work?
Avatar of syzygy

ASKER

I understand the difference between rdsk and dsk now.

on mounting /dev/rdsk/c0t6d0s?  I get not a block device, rickyr has explained this one

on mounting /dev/dsk/cot6dos? I get device does not exist, but I can see it in the directory.

On another (working) sun box the disk is mounted automatically when inserted, and teh mounting device is
/vol/dev/dsk/c0t6/s0  (and s1, s2, etc) on this system the c0t6 directory exists but is always empty, even with a CDROM in the drive.  volcheck will mount floppy disks but does not appear to even try to read the CDROM.

the boot cdrom command fails, it lists the boot device and teh cdrom access light comes on briefly.

I'm beginning to suspect a mechanical failure with teh drive.  If there any non-OS dependent way to verify this?  (as in does boot cdrom failing mean the drive is broken, since it is using the PROM to boot, not the OS?)



Avatar of syzygy

ASKER

The CDROM is broken.  I managed to get another sun box, and it wouldn't work on that either.  :(

What I've done now is borrow an internal CDROM from another system, open the sparc station 10 case, disconnect HDD 1, plug the CDROM in and rest is on a small cardboard box to keep it off the memory.

Thanks everyone for all your help, rickyr if you want to post an answer you can have the points...  In trying you suggestions I've managed to learn quite a bit about sun and unix.


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rickyr

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ASKER

I supose technically you didn't answer the question, but your answers were really helpful anyway.  :)