# CD drive dectected, but no /dev/cdrom [solved]

## vpoinot

I cannot access my CD/DVD drive although it seems to be detected by the kernel from dmesg output:

```
# dmesg

[...]

libata version 2.21 loaded.

[...]

ata_piix 0000:00:1f.2: version 2.12

ata_piix 0000:00:1f.2: MAP [ P0 P2 IDE IDE ]

scsi0 : ata_piix

scsi1 : ata_piix

ata1: SATA max UDMA/133 cmd 0x000101f0 ctl 0x000103f6 bmdma 0x0001bfa0 irq 14

ata2: PATA max UDMA/100 cmd 0x00010170 ctl 0x00010376 bmdma 0x0001bfa8 irq 15

ata1.00: ATA-6: ST9808211A, 8.03, max UDMA/100

ata1.00: 156301488 sectors, multi 8: LBA48

ata1.00: applying bridge limits

ata1.00: configured for UDMA/100

ata2.00: ATAPI: PHILIPS CD-RW/DVD-ROM SCB5265, TD15, max UDMA/33

ata2.00: configured for UDMA/33

scsi 0:0:0:0: Direct-Access     ATA      ST9808211A       8.03 PQ: 0 ANSI: 5

sd 0:0:0:0: [sda] 156301488 512-byte hardware sectors (80026 MB)

sd 0:0:0:0: [sda] Write Protect is off

sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00

sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA

sd 0:0:0:0: [sda] 156301488 512-byte hardware sectors (80026 MB)

sd 0:0:0:0: [sda] Write Protect is off

sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00

sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA

 sda: sda1 sda2 < sda5 sda6 sda7 sda8 >

sd 0:0:0:0: [sda] Attached SCSI disk

scsi 1:0:0:0: CD-ROM            PHILIPS  CDRW/DVD SCB5265 TD15 PQ: 0 ANSI: 5

[...]

```

Just in case, here the output of lspci:

```
00:00.0 Host bridge: Intel Corporation Mobile 915GM/PM/GMS/910GML Express Processor to DRAM Controller (rev 03)

00:01.0 PCI bridge: Intel Corporation Mobile 915GM/PM Express PCI Express Root Port (rev 03)

00:1c.0 PCI bridge: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) PCI Express Port 1 (rev 03)

00:1d.0 USB Controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB UHCI #1 (rev 03)

00:1d.1 USB Controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB UHCI #2 (rev 03)

00:1d.2 USB Controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB UHCI #3 (rev 03)

00:1d.3 USB Controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB UHCI #4 (rev 03)

00:1d.7 USB Controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) USB2 EHCI Controller (rev 03)

00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev d3)

00:1e.2 Multimedia audio controller: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) AC'97 Audio Controller (rev 03)

00:1f.0 ISA bridge: Intel Corporation 82801FBM (ICH6M) LPC Interface Bridge (rev 03)

00:1f.2 IDE interface: Intel Corporation 82801FBM (ICH6M) SATA Controller (rev 03)

00:1f.3 SMBus: Intel Corporation 82801FB/FBM/FR/FW/FRW (ICH6 Family) SMBus Controller (rev 03)

01:00.0 VGA compatible controller: nVidia Corporation NV41 [Quadro FX Go1400] (rev a2)

02:00.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5751 Gigabit Ethernet PCI Express (rev 01)

03:01.0 CardBus bridge: Texas Instruments PCI6515 Cardbus Controller

03:01.5 Communication controller: Texas Instruments PCI6515 SmartCard Controller

03:03.0 Network controller: Intel Corporation PRO/Wireless 2915ABG Network Connection (rev 05)

```

The problem is there is no /dev/cdrom device: could it be a problem with udev? I'm running udev-115-r1, and have not tweaked anything in there (kernel 2.6.23).

Any clue about what I am missing?Last edited by vpoinot on Thu Nov 22, 2007 8:19 pm; edited 1 time in total

----------

## EzInKy

Your CDROM may be called /dev/sr0 with the new SATA/PATA drivers.

----------

## HymnToLife

Please paste contents of /etc/udev/rules.d/70-persistent-cd.rules

----------

## vpoinot

No /dev/sr0 either.

I have no file /etc/udev/rules.d/70-persistent-cd.rules... Here is the content of the rules.d folder:

```
$ ls -l /etc/udev/rules.d/

total 64

-rw-r--r-- 1 root root  191 Oct 20 10:08 05-udev-early.rules

-rw-r--r-- 1 root root 1466 Oct 20 10:08 30-kernel-compat.rules

-rw-r--r-- 1 root root 9220 Oct 20 10:08 50-udev.rules

-rw-r--r-- 1 root root 1424 Oct 20 10:08 60-persistent-input.rules

-rw-r--r-- 1 root root 4080 Oct 20 10:08 60-persistent-storage.rules

-rw-r--r-- 1 root root  411 Oct 20 10:08 61-persistent-storage-edd.rules

-rw-r--r-- 1 root root 1010 Nov 14 21:44 64-device-mapper.rules

-rw-r--r-- 1 root root  454 Sep 30 22:47 70-persistent-net.rules

-rw-r--r-- 1 root root  390 Oct 20 10:08 75-cd-aliases-generator.rules

-rw-r--r-- 1 root root 1518 Oct 20 10:08 75-persistent-net-generator.rules

-rw-r--r-- 1 root root  666 Oct 20 10:08 80-drivers.rules

-rw-r--r-- 1 root root   82 Nov 15 21:46 90-hal.rules

-rw-r--r-- 1 root root  280 Oct 20 10:08 90-network.rules

-rw-r--r-- 1 root root  233 Oct 20 10:08 95-udev-late.rules

```

Does it look bad?

----------

## cyrillic

In order to be able to mount data CDs/DVDs , you want SCSI CDROM support.

And to do low level stuff like CD burning, and audio ripping, you want SCSI generic support.

```
Device Drivers  --->

  SCSI device support  --->

    <M> SCSI CDROM support

    <M> SCSI generic support 
```

----------

## vpoinot

Thanks a lot, it now works fine.

(I think I will never understand all this ATA/SATA/PATA/SCSI/ATAPI mumbo jumbo: as far as I know, my CD-ROM does not use SCSI, so why do I have to compile SCSI support in the kernel? This is a mystery to me...)

----------

## hfk

No mystery but history.

The first CDROM drives had a proprietary or a SCSI interface.

Then came the APAPI drives using the ATA disk interface.

ATAPI is an emulation of the SCSI interface (commands etc.)

....

----------

