LinuxQuestions.org - CDROM found in /proc/scsi/scsi but no /dev entry. Trying to make livecd.

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CDROM found in /proc/scsi/scsi but no /dev entry. Trying to make livecd.

I am trying to debug the Mandriva 2009 mklivecd script. It's well known that it has been broken for some time so I am attempting to bring it up to date because I need it to work. I am using kernel 2.6.27.5-desktop-2mnb.

When I boot the ISO in VirtualBox it loads all the modules OK but can't find the cdrom. I suspect there is some module I have missed out but can't guess what it is.

The CDROM ISO is presented as an ide device by VirtualBox (i.e. I'm not doing anything unusual) and appears to be detected as a SCSI device.

I have also attached a virtual IDE disk but that also doesn't show up in /dev.

Code:

cat /proc/scsi/scsi

Attached devices:

Host: scsi1 Channel:00 Id: 00 Lun: 00

  Vendor: VBOX  Model: CD-ROM  Rev: 1.0

  Type:  CD-ROM              ANSI SCSI

Code:

lsmod (only modules and used by listed since I have no copy/paste from terminal)

Module                        Used by

3w_xxxx                        Live

usb_storage                Live

ehci_hcd                Live

ohci_hcd                Live

uhci_hcd                Live

usbcore                        usb_storage,ehci_hcd,ohci_hcd,uhci_hcd, Live

i2c_piix4                Live

i2c_core                i2c_piix4, Live

scsi_transport_sas        Live

ide_scsi                Live

ide_core                ide_scsi, Live

isofs                        Live

mptbase                        Live

sd_mod                        Live

crc_t10dif                sd_mod, Live

sr_mod                        Live

loop                        Live

ata_piix                Live

ahci                        Live

libata                        ata_piix,ahci, Live

scsi_mod                3w_xxxx,usb_storeage,scsi_transport_sas,ide_scsi,sd_mod,sr_mod,libata, Live

dock                        libata, Live

Code:

ls /dev

core        fd        null        pts        stderr        stdin        stdout

CDROM found in /proc/scsi/scsi but no /dev entry. Trying to make livecd. SOLVED

OK. I'm answering my own post here :-)

The problem turned out to be that udev has depreciated the udevstart command that the initrc script was using to generate the device nodes.

Getting it to work with Mandriva 2009 involves using the start_udev script. This in turn depends on /etc/rc.d/init.d/functions being present which doesn't work with busybox's ash so bash and it's libraries also need to be copied.

Once the new udev start script is happy then the CDROM is available as /dev/sr0 as expected.

I now have a working Live CD so I have posted the patches to this bug report.
https://qa.mandriva.com/show_bug.cgi?id=46068