N. Harrison Ripps

Email: <n.harrison.ripps AT SPAMFREE gmail DOT com>

I'm an Ubuntu Linux convert and a huge fan of the Ubuntu project. I'm adding a wiki page for myself so that I can track pages of interest.


Recently I did a fresh install of 5.10 onto a new system and encountered an odd problem. Even though I'd started the install from a CDROM, item "hdc", wasn't present in my /dev directory after installation.

If you are unfamiliar with the device naming scheme, devices labelled hd* refer to items on your IDE controllers. hda and hdb are the primary (master) and secondary items on the first IDE controller (usually hard drives), and hdc and hdd are the same respective items on the second IDE controller.

On many systems, the master device on the second IDE controller is a CDROM or DVDROM drive. Such is the case with the system I was working on. And mysteriously, hdc hadn't been created, even though the drive was working throughout installation.

Here's how I remedied the situation:

Creating hdc

# In a terminal, I cd'ed to /dev. # I created hdc using this command:

  • sudo /dev/MAKEDEV hdc

This created the entry, but it did not associate the entry with a driver. In other words, I wasn't finished yet.

Loading the right kernel module

The next part of this was to make sure I was loading the right kernel module. In my case, since I was trying to get an ATAPI CDROM drive to work, the module in question was 'ide-cdrom', but your mileage may vary.

sudo'ed, I editied /etc/modules and added the following on a new line:

  • ide-cdrom

Modifying GRUB

This final part is the scary part. If you mess up GRUB, you can potentially kill your whole system.

# First, I cd'ed to /boot/grub # Next, as root, I opened the menu.lst file:

  • sudo emacs menu.lst

Here's a typical entry in menu.lst:

  • title Ubuntu, kernel 2.6.12-10-386 root (hd0,0) kernel /boot/vmlinuz-2.6.12-10-386 root=/dev/sda1 ro quiet splash initrd /boot/initrd.img-2.6.12-10-386 savedefault boot

Copy the entry that your system boots with (normally the topmost entry with a 'savedefault' line in it) an paste it below the original entry, but make two changes: first, change the name to something informative--

  • title Ubuntu, kernel 2.6.12-10-386 [EXPERIMENTAL]

And second, add the module driver information to the new entry's boot line:

  • kernel /boot/vmlinuz-2.6.12-10-386 root=/dev/sda1 hdc=ide-cdrom ro quiet splash

Reboot, cross fingers

Reboot the system, and be sure to watch it so that you can jumping in to the boot menu during GRUB's 5 second pause. Select the name of your experimental boot item and see what happens. For me, fortune favored the foolish. I put in a CD and it was automatically mounted. If you've run into the same problem, hopefully this will help you get your drive recognized and working again, too.


NHarrisonRipps (last edited 2008-08-06 16:19:04 by localhost)