re: where'd my cdrom go?

ergo_sum · 10-22-2003, 08:40 PM

Hello All:

Newbie here. When I type:

ls -l /dev/cdrom

I get:
lrwxrwxrwx 1 root root 9 Aug 27 14:38 /dev/cdrom -> /dev/scd0

Can someone please explain this to me. I used to have my cdrom under /dev/cdrom. Does the previous line mean I now have it under /dev/scd0? What does "->" mean?

If my cdrom is now scd0, then how do I mount it? And how did it become scd0 when it used to be cdrom?

I used to mount my cdrom with:

mount -t iso9660 -v /dev/cdrom /mnt/cdrom

Now when I type that I get:

mount: block device /dev/cdrom is write-protected, mounting read-only
mount: No medium found

I have RH 7.3, using kde on the desktop.

Anxiously awaiting relevant replies.

Thanks,

ergo_sum

AltF4 · 10-22-2003, 08:53 PM

/dev/scd0 --> first SCSI CD-ROM
/dev/cdrom --> symbolic link to your CD-ROM (for IDE CD-ROM: e.g. /dev/hdc)

ergo_sum · 10-22-2003, 10:13 PM

Thanks, AltF4.

As posted, I'm a newbie. And, by the questions I asked, there's a whole bunch I don't understand.
That's why I always ask for "relevant" replies.
I'm interested in answers to my questions (hence relevance, yo).

Your post looks like a blurb (blurbs?) to me. I don't know which questions it answers.
Can you please be patient, and maybe use verbs and subjects and objects?

thanks

ergo_sum

ergo_sum · 10-22-2003, 10:18 PM

Oh, here's my /etc/fstab

I'm way lost here.
A little help please.

ergo_sum

ergo_sum · 10-22-2003, 10:19 PM

Sorry.
Here it is, my fstab:

LABEL=/boot /boot ext3 defaults 1 2
none /dev/pts devpts gid=5,mode=620 0 0
none /proc proc defaults 0 0
none /dev/shm tmpfs defaults 0 0
/dev/hda3 swap swap defaults 0 0
/dev/cdrom /mnt/cdrom iso9660 noauto,owner,kudzu,ro 0 0
/dev/fd0 /mnt/floppy auto noauto,owner,kudzu 0 0

Onemessedupjedi · 10-22-2003, 10:47 PM

I really don't know what you are asking but I understand what he said. In windows you see links all over the place. Well, cdrom is just a link. The arrow represents that the drive is linked to scd0. If you have a IDE drive you want it pointing the the IDE device which is /dev/hdc(I think that's actually supposed to be a hard drive device name but what do I know..)

*twiddles thumbs waiting for program to finish making*

h/w · 10-22-2003, 11:04 PM

well, /dev/cdrom -> /dev/scd0 means what it looks like - its pointin to whatever.
it cant have just changed to a scsi drive on its own, ya know. what'd u do? im assuming you didnt compile ur own kernel from your questions - so your drive shouldnt have scsi support?

find out which device under /dev is ur cd-drive. it should have come up under dmesg during startup.

do a

Code:

dmesg | grep 'cd'

or (if you dont get anything with the above) a

Code:

dmesg | grep 'hdc'

that should tell you where the drive is.

once you get it, and if its saying something other than "scd0", go remove it with

Code:

rm /dev/cdrom

next make a new link to the drive with

Code:

ln -s /dev/xxx /dev/cdrom

where xxx is what you saw was the device for the drive from above.

and then to check it, do :

Code:

mount /dev/cdrom /mnt/cdrom
ls /mnt/cdrom
umount /mnt/cdrom

hope that helps

ergo_sum · 10-23-2003, 08:11 AM

Yes!!!!

But lo, I feel like such a dweeb newbie. Enclosed is output from

dmesg | grep 'hdc'

Kernel command line: ro root=/dev/hda2 hdc=ide-scsi
ide_setup: hdc=ide-scsi
ide1: BM-DMA at 0xffa8-0xffaf, BIOS settings: hdc

MA, hdd

io
hdc: LG CD-RW CED-8080B, ATAPI CD/DVD-ROM drive
hdc: DMA disabled

So, is my cdrom hdc?
And would linking to the cdrom be made by writing:

ln -s /dev/hdc /mnt/cdrom

Anxiously awaiting your reply.

ergo_sum

ergo_sum · 10-23-2003, 09:16 AM

Sorry, I don't use smilies and am very concerned re: how they got there in my post.

here is output again from dmsg | grep 'hdc'

Kernel command line: ro root=/dev/hda2 hdc=ide-scsi
ide_setup: hdc=ide-scsi
ide1: BM-DMA at 0xffa8-0xffaf, BIOS settings: hdc

MA, hdd

io
hdc: LG CD-RW CED-8080B, ATAPI CD/DVD-ROM drive
hdc: DMA disabled

h/w · 10-23-2003, 09:33 AM

well, it seems to have picked up the drive fine.
do a "dmesg | grep 'cd'" as i mentioned before, it should tell you what device the drive is being pointed to. in my case its 'sr0', so its /dev/sr0.
so i went and made a /dev/cdrom -> /dev/sr0

ergo_sum · 10-23-2003, 11:03 AM

Well let me acknowledge my newbieness.

So what is my cdrom?

Anxiously awaiting your reply.

ergo_sum

trickykid · 10-23-2003, 11:06 AM

Quote:

Originally posted by ergo_sum
Sorry, I don't use smilies and am very concerned re: how they got there in my post.

Smilies are defined by particular characters on your keyboard, usually most of them will start with a colon ( : ) or semi-colon ( ; ) followed by another character.

Like putting : and a D together will make

Putting ; and a ) together will make a

Its not a matter of that you put them there or not, its what's typed and how they are recognized.. If you don't want these smilies to show up, you'll have to put a space between the characters that create them. Or turn smilies off in your profile but that won't stop other members that have them on to not see them.

Regards.

h/w · 10-23-2003, 11:46 AM

anxiously awaiting the ouput of:
dmesg | grep 'cd'

ergo_sum · 10-24-2003, 09:01 AM

When I input dmesg | grep 'cd'

I get nothing, just a new prompt.

ergo_sum

ergo_sum · 10-24-2003, 09:09 AM

h/w

Unbelievable as is sounds I did install rh on this box. And I have no idea how my cdrom is now somehow a scuzzy drive--I don't have a scsi card.

So, w/ the output from both
dmesg | grep 'hdc'
and
dmesg | grep 'cd'

posted, please tell me what my cdrom is. Is it hdc, and if so, then should the sym link be:

ln -s /dev/hdc /mnt/cdrom

Please let me know.

And thanks,

ergo_sum