NSLU2-Linux
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After fumbling through the dark with something that should be an easy task, I finnaly managed to get an external CDROM attached to my Slug. This is how you can do it too.

First things first

Get yourself an external USB CDROM/DVD drive and plug it in to the Slug. I purchased an ADS USB2?.0 external enclosure and put an IDE Lite-ON DVDRW (SHW-1635S) drive in it. One warning though. Most HP and Sony drives marked as internal? will not work with generic external USB cases. I'm not sure why but the first DVD drive I tried out, HP DVD640cI?, was not recognised in Linux(Debian) or Windows XP.

Are We Recognised

When you plug the external USB drive in you should see messages like these from 'dmesg'

usb 1-2.3: USB disconnect, address 8
usb 1-2.3: new high speed USB device using ehci_hcd and address 9
scsi6 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 9
usb-storage: waiting for device to settle before scanning
Vendor: LITE-ON Model: DVDRW SHW-1635S Rev: YS0J?
Type: CD-ROM ANSI SCSI revision: 00
sr0: scsi3-mmc drive: 48x/48x writer cd/rw xa/form2 cdda tray
Attached scsi CD-ROM sr0 at scsi6, channel 0, id 0, lun 0
usb-storage: device scan complete

If you don't see the 'Vendor' stuff there's nothing that can be done. Your drive/enclusure combination do not work together. This isn't a Linux issue but a Firmware/BIOS issue between the drive and enclosure. Try another drive/enclosure combination, or give up.

If you seen the 'Vendor' stuff and the message regarding 'Attached scsi CD-ROM sr0' then you may be in luck! Linux recognised the drive and has attached it.

Put a CDROM or DVDROM in the drive and attempt to mount it.

  • mount -t iso9660 -o ro /dev/sr0 /mnt

(you may have another device name. I have seen /dev/scd0)

No returned errors will mean that you have successfully mounted the CDROM under /mnt.

Any error about missing block device will mean that you need to install and load some kernel modules.

Required Kernel Modules

You know that your drive is supported by does not get attached so you now have to verify that all the needed kernel modules have been installed and loaded.

These kernel modules have to be installed for CDROM support.

  • ipkg install kernel-module-cdrom
  • ipkg install kernel-module-sr-mod
  • ipkg install kernel-module-isofs

They also have to be loaded. Do a 'lsmod' and check to see if they are. You should see something like this.

ModuleSizeUsed by
isofs266840
sr_mod94760
cdrom295642 sr_mod

To load the modules you can do this.

  • modprobe cdrom
  • modprobe sr_mod
  • modprobe isofs

Check 'dmesg' again and make sure that you have 'Attached scsi CD-ROM' messages.

Put a CDROM or DVDROM in to the drive and try to mount it.

  • mount -t iso9660 -o ro /dev/sr0 /mnt

(you may have another device name. I have seen /dev/scd0)

No returned errors will mean that you have successfully mounted the CDROM under /mnt.

view · edit · print · history · Last edited by mrkzander.
Originally by mrkzander.
Page last modified on March 31, 2006, at 08:47 PM