# /dev/cdroms/cdrom* disappear and no CD drive after reboot .?

## yipmister

hi all,

i'm a newbie trying to play some music one day (first time i tried) from an audio CD. i mounted the CD onto /mnt/cdrom, then did some stuff and cd to /mnt and then umount /mnt/cdrom,.. for some reason the CD starts spinning for a while.. and then afterwards, i am not able to reject the CD and even mounting it again dont work.. it gave me some error about bad header (sorry   i am not able to recover the exact message since now i get a different error message when i try to mount).. so i tried the windoze approach of rebooting.. 

strange enough, after reboot the sym links for my 2 CD drives (one CD one CD-RW) disappeared (/dev/cdroms/cdrom0 and cdrom1 ) so then i search around the forum for some clue.. one possibility is the conf file for devfs might be overwritten (so that now its wrong) when i did etc-update.. but then i think the problem is worse than that since when i check dmesg it doesnt show that the boot process sees the 2 CD drives at all!!

dmesg | grep hd shows

```

Kernel command line: root=/dev/hda5

    ide0: BM-DMA at 0xffa0-0xffa7, BIOS settings: hda:DMA, hdb:pio

hda: Maxtor 5T060H6, ATA DISK drive

hda: 117187500 sectors (60000 MB) w/2048KiB Cache, CHS=7294/255/63, UDMA(100)

grsec: mount /dev/hda5 to / by (mount:22722) UID(0) EUID(0), parent (rc:19809) UID(0) EUID(0)

grsec: mount /dev/hda5 to / by (mount:21759) UID(0) EUID(0), parent (rc:19809) UID(0) EUID(0)

grsec: mount /dev/hda7 to /tmp by (mount:10942) UID(0) EUID(0), parent (rc:19809) UID(0) EUID(0)

grsec: mount /dev/hda8 to /var by (mount:10942) UID(0) EUID(0), parent (rc:19809) UID(0) EUID(0)

grsec: mount /dev/hda9 to /usr by (mount:10942) UID(0) EUID(0), parent (rc:19809) UID(0) EUID(0)

grsec: mount /dev/hda10 to /home by (mount:10942) UID(0) EUID(0), parent (rc:19809) UID(0) EUID(0)

```

versus it should have hdc and hdd in there... but its not.

this is a comparable part from /var/log/messages

```

Sep 14 19:13:39 spear ide0: BM-DMA at 0xffa0-0xffa7, BIOS settings: hda:DMA, hdb

:pio

Sep 14 19:13:39 spear ide1: BM-DMA at 0xffa8-0xffaf, BIOS settings: hdc:DMA, hdd

:DMA

Sep 14 19:13:39 spear hda: Maxtor 5T060H6, ATA DISK drive

Sep 14 19:13:39 spear hdc: CRD-8482B, ATAPI CD/DVD-ROM drive

Sep 14 19:13:39 spear hdd: SONY CD-RW CRX140E, ATAPI CD/DVD-ROM drive

Sep 14 19:13:39 spear ide0 at 0x1f0-0x1f7,0x3f6 on irq 14

Sep 14 19:13:39 spear ide1 at 0x170-0x177,0x376 on irq 15

Sep 14 19:13:39 spear blk: queue c0173344, I/O limit 4095Mb (mask 0xffffffff)

Sep 14 19:13:39 spear hda: 117187500 sectors (60000 MB) w/2048KiB Cache, CHS=729

4/255/63, UDMA(100)

Sep 14 19:13:39 spear hdc: ATAPI 48X CD-ROM drive, 128kB Cache, UDMA(33)

Sep 14 19:13:39 spear Uniform CD-ROM driver Revision: 3.12

Sep 14 19:13:39 spear hdd: ATAPI 32X CD-ROM CD-R/RW drive, 4096kB Cache, UDMA(33

)

Sep 14 19:13:39 spear Partition check:

Sep 14 19:13:39 spear /dev/ide/host0/bus0/target0/lun0: p1 p2 < p5 p6 p7 p8 p9 p

10 >
```

please help!!! any advice and pointers would be appreciated!!! thanks   :Smile: 

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## NeddySeagoon

yipmister,

The easy one first. You don't mount music CDs to play them. You just put them in the drive and run the payer of your choice. CDs with mp3 files on them count as data CDs since they have a real iso9660 filesystem. 

Have you tried to set up SCSI emulation for your CD-RW?

That would mean that your kerenl command lind contains hdd=ide-scsi. If that is there and scsi emulation is not working, your drive(s) will disapper.

Check for /dev/sr0.

The softlinks in /dev/cdroms will be OK for either configuration because devfsd writes them at boot time, depending on what it finds.

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## yipmister

First of all, thank you so much for responding, NeddySeagoon.. thank you for your time.

 *NeddySeagoon wrote:*   

> 
> 
> yipmister,
> 
> The easy one first. You don't mount music CDs to play them. You just put them in the drive and run the payer of your choice. 
> ...

 

oh i always thought that in order for the player to navigate and be able to see the actual song files you will need to mount the CD.... hmm if you dont mount them how would the player software knows where to find it...?  :Crying or Very sad: 

 *NeddySeagoon wrote:*   

> 
> 
> Have you tried to set up SCSI emulation for your CD-RW?
> 
> That would mean that your kerenl command lind contains hdd=ide-scsi. If that is there and scsi emulation is not working, your drive(s) will disapper.
> ...

 

in my kernel command line, there is no hdd=ide-scsi... and may i take this moment to beg for forgiveness for my extreme stupidity for i am still in the proess of converting from windoze.. (i still use it quite a bit)

 *Quote:*   

> Kernel command line: root=/dev/hda5

 

fwiw, this is the output from lsmod

```
Module                  Size  Used by    

floppy                 47036   0  (autoclean)

i810_audio             23560   0 

soundcore               3364   2  [i810_audio]

ac97_codec              9800   0  [i810_audio]

eepro100               18420   1 

mii                     2160   0  [eepro100]

nvidia               1538016  10 

ide-scsi                7600   0 

usb-storage            55608   0  (unused)

hid                    12468   0  (unused)

uhci                   23008   0  (unused)

usbcore                55264   1  [usb-storage hid uhci]
```

i put in the following modules (in this order) in /etc/modules.autoload.d/kernel-2.4

ide-scsi, sg, sr_mod, nvidia

(actually while i was installing i dont remember exactly what kernel version i have... how do u find that out? )   :Embarassed: 

and sg and sr_mod failed to load on start up (another problem i have, i think i put those in while learning how to get my CD writer to work...)

i found a good document just now by forum search on CD writing and scsi emulation thanks to peaceful

https://forums.gentoo.org/viewtopic.php?t=68321&highlight=cd+burning+scsi+emulation&sid=80f3f75ee962ef28285b3f6c92fbad3a

in it he mentioned that if a person have a 2.6 kernel it would be much easier to get the CD writer to work?... would someone care to show me now pleasseee.. (if its the same way then thats great too) since my CD drive detection failure problem can be related to my past failed attempt to getting the CD writer to work..  i might be able to hit 2 birds with one stone..... 

actually the truth is i still am not sure what it is that is causing my cd drives not getting detected.. as you can see from my previous post, the only thing the boot process is was hda..not hdc or hdd....  :Sad: 

i'll be extremely grateful if someone can help to point out to me how to approach this problem and what to do.. 

thanks in advance guys!!!

----------

## NeddySeagoon

yipmister,

From your first post

 *Quote:*   

> dmesg | grep hd shows
> 
> Code:
> 
> Kernel command line: root=/dev/hda5
> ...

 

You should also have a line here that looks like 

 *Quote:*   

>     ide1: BM-DMA at 0xf008-0xf00f, BIOS settings: hdc:DMA, hdd:DMA

 

which shows your second IDE channel being detected.

Some reasons why it may not get detected:-

1. Its turned off in the BIOS

2. Both drives are set to master (or both to slave) with the drive jumpers

3. You have run out of interrupts.

4. A loose or dead IDE cable.

5. One or more dead drives

To fix 1, go into the BIOS settings and check. Turn it on if required

To fix 2, go the the drive manufactuers websites and get the jumper settings. Check that one drive is set to master and the other is set to slave. The info will be on the lables on the drives but you will have to remove them to see it.

To fix 3, build the kerenl with interrupt sharing enabled

To fix 4, press the IDE cablesfully home (and on the motherboard);. A dud can on;y be diagnosed by replacement. 

you find out about your kernel with 

```
uname -a
```

Kernel 2.6 does have support for ATAPI CD writing (without SCSI Emulation) but I haven't tried it and have read mixed reports. I suspect that the sg and sr_mod modules are not loaded becase they can't find any hardware.  When your ide1: does appear, the devices will come up as hdc and hdd, since you don't have the ide-scsi entries on the kernel command line.

----------

## yipmister

Hi Neddy, thanks for the response again!

 *NeddySeagoon wrote:*   

> 
> 
> Some reasons why it may not get detected:-
> 
> 1. Its turned off in the BIOS
> ...

 

i think i can eliminate some of these possibilities since the sequence of events is as follows:

1. it was performing normally... 

2. I mount and umount a CD

3. CD starts spinning for a little while for some reason (~1 min)

4. i wasnt able to mount it again.. 

5. i rebooted hoping it will solve the problem but after reboot, the IDE channel 1 and the 2 CD drives are not even detected..the sim links for cdroms gone.

therefore i think i can savely concluded that the BIOS setting wasnt changed, the jumpers are in the right places, the number interrupts i am using is the same and therefore have not run out... loose cable.. 

but i did open the box to unplug and plug in the cable all the way.. (maybe it'll somehow "reset" it).. i just started up the machine...it didnt help...

i am seriously hoping that it is not the possibility of bad cable or bad drive(s)... (now that i put linux on it, Dell would find the excuse not to support it)

another piece of information is.. when i press eject on the CD-RW drive (the drive that i didnt do anything to in the first place), it responds to me... but when i press eject on the regular CD drive it doesnt respond.... (the situation has been like this since my little mount, umount events)

please please please.... any other ideas.... ??? i'm desperate

yipmister

----------

## NeddySeagoon

yipmister,

Its looking like the motherboard IDE chip, the cable or one of the drives.

Your CDs aren't LGs are they? 

They have a bug whereby the drive interprets the 'flush cache' command as an instruction to erase the firmware. Only CD-ROMS are affected. Google for details if you think it may affect you.

Here's three tests that you can do in any order.

Pull the IDE cable off one drive.

Is IDE1: detected now?

Yes - That will be the disconnected drive faulty then.

Repeat for the other drive. Linux is OK about only a slave drive on an IDE cable.

Disconnect the IDE cable from both drives.

Is IDE1 dectected now?

Disconnect the cable from the motherboard.

Now what?

Be sure to switch the PSU off so that you don't have 5v STBY on when you are doing all of this.

Dells hardware support is one of the best in the industry. I am aware of several corporate usrs that by Dell because of the 3 year warranty, then dispose of the equipment as soon as it goes faulty out of warranty.

If you can, swap out the IDE cable thats about the last thing to do.

Its worth checking the BIOS. The settings are stored in a battery backed area of storage that can be both read and written by the CPU. Strange things like that do happen from time to time.

----------

## yipmister

sorry for the late reply... been the holidays and stuff... just came back from a ski trip...   :Laughing: 

 *NeddySeagoon wrote:*   

> 
> 
> Pull the IDE cable off one drive.
> 
> Is IDE1: detected now?
> ...

 

this was my first diagnose.. and yes!!! once i disconnected the CD-ROM, the boot process was much quicker.. and the IDE channel one is detected along with the Sony CD-RW..!!!! so this means that the CD-ROM drive is faulty...... this leads me to look up the model name and manufacturer's name...

 *NeddySeagoon wrote:*   

> yipmister,
> 
> Its looking like the motherboard IDE chip, the cable or one of the drives.
> 
> Your CDs aren't LGs are they? 
> ...

 

WOW, how did u know that?....are u sure u dont have a crystal ball in front of ya ?   :Cool: 

well i actually didnt know at first.. but after i type the model name of my CD rom into google along with the keyword "bug".. i found out that my drive IS one of the affected ones by LG. (in /var/log/messages it just said CRD-8482B, didnt say manufacturer's name..)

now i am in the process of upgrading the firmware... though i wonder if anyone else have experience with this so may lend me some advice so i wont mess up   :Embarassed:   ........ since if u mess up ur drive can be gone...

here's what i did so far....

i downloaded the crd-8482b linux.zip and i also took a look at Dead.gif.

there's some discrepancy though.. between the instruction on Dead.gif and the readme from "crd-8482b linux.zip". In particular, Dead.gif says its for recovering physical dead drives and tells u to ...

1) MS-DOS mode boot

2) change jumper setting (shown picture)

3) push drive's eject button

4) drive power on during pushing drive's eject button.

5) check drive's LED toggle or LED ON.

6) Release the eject button

7)c:\temp>exe_file firmware_file

 :Cool:  change the jumper setting back

9) reboot...

but in the read me of the zip file, it never tells u to change the jumper setting.... in what situation should a person change it and which dont? (after this little incident, my drive does not respond to my pushing of the eject.. i guess this means the drive is dead) but would it be alive again once i upgrade the firmware? in other words, is changing the jumper setting absolutely necessary, or could it be damaging if it is not necessary but i did it anyway?....

here's one more retarded question... in step one above.. i basically just do the following rite?

1) in my windows OS (winXP), format a new floopy (the instruction said the dos disk has to be MS-DOS 6.0... how would i know if it is???   :Embarassed:  )

2) copy the 2 files (exe for the upgrade and the firmware file itself) onto the floopy

3) put the floopy into machine with affected drive..

4) reboot... and then type in "a:\>exe_file  firmware_file"

5) wait.. 

6) hopefully its successful and then reboot again ..

thanks so much for Neddy's help so far again.... he's been like a psychic   :Wink: 

hopefully someone has done this before.....

thanks in advance everyone!!!!!!

----------

## NeddySeagoon

yipmister,

I have not done the drive firmware update but often the drive will want to be the only thing on the IDE cable when the update is done and will only respond to the update program when its set to master. In short if in doubt, configure the drive to master.

The remains of the firmware in the drive will interpret the eject button press during power up as a command to go into a special mode - don't do the normal thing of running the firmware.

You need a DOS 6.x boot floppy - formatting in XP won't get you that. 

You need the system files too.

----------

