"Kernel panic" :VFS: Unable to mount root fs on 08:05"
 

I have been dual booting "Windoz" (hda1) and slackware 11 (RTAI - hda 5) old system.
The problem happen after I installed slackware 13(sda8) on the same hard drive. I was able to mount my old slack11 (now (sda5)) to slack13 to read. So I wanted to boot to slack11.
MY Lilo on slack 13:
# Windows bootable partition config begins
other = /dev/sda1
label = Windows
table = dev/sda
# Windows bootable partition config ends
# Linux bootable partition config begins
image = /boot/vmlinuz
root = /dev/sda8
label = Slackware13
read-only
# Linux bootable partition config ends
# Linux bootable partition config begins

image = /rtai/boot/vmlinuz
root= /dev/sda5
label= "Slackware11"
read-only
# Linux bootable partition config ends

Now when I boot to Slackware11 I get:

VFS: Cannot open root device "805" or 08:05
Please append a correct "root=" boot option
Kernel panic :VFS: Unable to mount root fs on 08:05

How can I boot a old "hda" image on "sda" system.
With a floppy I can go back to Slackware11. Need help?

*** FAULTY ******

Just change this
to this
make sure /rtai/boot/vmlinuz is reachable (mounted) and run lilo. The root= parts are passed to the kernel on boot up so they are not checked when you install lilo. Slackware 11 is expecting the drive to be /dev/hda and Slackware 13 /dev/sda.

After I changed the /dev/sda5 to /dev/hda5, I received the following error.

Sorry: Fatal: Illegal 'root=' specification: /dev/hda5

I tried combinations of "hda5" with "fstab" & "mtab" no success.

Is their a command that would allow /dev/sda5 = /dev/hda5 in "lilo" thru append. I don't know.

I have tried the reverse used the floppy to move back to slackware11 than I tried to boot slack13. I could mount, but could not boot to slack13

I don't know if this already worked in slackware-11, but you could try specifying root by UUID or LABEL - take a look at 'man lilo.conf'

There are some questions about your lilo.conf.
Did lilo run without any errormessages?
Why did you insert quotationmarks in the lineIf Slack11 recognizes your disk as /dev/hda and Slack13 as /dev/sda, I'd suggest to boot Slack11 like Windows (with "other"). Change the lilo.conf in you old Slackware-11 installation from "boot=/dev/hda" to "boot=/dev/hda5". This will write your Slack11 lilo onto the mbr of the partition (not the disk).

Then add Slack11 like Windows with "other" in lilo.conf of the Slackware-13 installation.don't forget to boot Slack-11 and execute lilo there. You may remove the line "Prompt" in your lilo.conf in Slackware-11, since you'll not have to chose an operatingsystem there.

Markus

try this

Colorpurple21859: The "append" did it I was able to go back to 13 and make changes.

Thanks so much. Great fix mix mode of new "sda" and old "hda". Thanks

Oops ! I think I owe you an apology. I have just tested this on my system and I now see my advice was very wrong. I was under the impression that lilo did not check the root setting until it booted. I'm sure it used to be that way but I may be mixed up there.

Sorry for leading you astray. I should have tested my recommendation before posting as I usually always do. In any case I'm glad you managed to fix your problem thanks to colorpurple21859's idea.

Edit: I hope no one minds but I have added to my original post flagging it as being incorrect - just in case anyone reads the first reply to the problem and tries to implement my original fix which won't work.