Getting a Kernel Panic: Error, newbie needs some help

[Jeff Vian]

David I. Wright wrote:

> I have a Compaq Proliant 2500.  It is a dual Pentium Pro 200 system 
> with 2 Pentium Pro 200 /512 cache processors and has 512 Meg of 
> memory.  The memory is 4 each 128 Meg sticks installed in the 4 memory 
> slots.
>
> When I try to install Fedora by booting up on the first CD and hit 
> enter with no options it displays many lines of stuff and then 
> displays a message box that says I do not have enough RAM to do the 
> install.  This message box has an OK button in it that is 
> highlighted.  If I hit enter the system runs a halt system and then 
> reboots.   If I type the following at the command line:
>    linux mem=512M

indications of likely problems with memory.  :-)

>
> It then displays many lines of stuff with the following being the last 
> four lines:
>
> Net4: Unix domain sockets 1.0/SMP for Linux NET4.0
> EXT2-fs: unable to read superblock
> isofs_read_super: bread failed, dev=09:02 iso_blknum=16, block=32
> Kernel panic: VFS: unable to mount root fs on 09:02
>
> I have tried RH 9.0 and Suse 9.0 with the same general results except 
> the dev=xx:xx was different for Suse 9.0.
>
> One curios note.  I tried to install Suse 8.0 awhile back and managed 
> to do so but it was by accident.  It would not install without some 
> options on the command line.  After much searching doc's etc. I found 
> that I could disable the probing for USB stuff by using the following 
> on the command line:
>
>   hwprobe=-c03:*:*
>
> It seemed to insist that I had a USB mouse instead of the PS/2 mouse 
> that was plugged into the box.  

Bios settings maybe?  or a bad/unsupported board.  Or maybe still memory 
problems that confuse it.

> This got me further into the install process but would still hang. I 
> then discovered mem=512M option but it only got me a little further 
> into the install process where it would also just hang. I had given up 
> on this when I started checking some extra memory sticks I had in 
> order to identify what size they were.  I removed one of the 128 Meg 
> memory sticks and used this memory slot to test a stack of memory 
> sticks I had.  One at a time I would check a stick of memory put it in 
> a stack for its size and try the next one.   The last one was a 16 Meg 
> or 32 Meg, I don't remember, but I went ahead and let it boot with the 
> two options I had previously been using trying to install Suse 8.0.  I 
> watch in disbelief as it booted up and let me start the install.  I 
> was able to install and use the system with Suse 8.0  Of course I 
> tried all this with Fedora, RH9 and Suse9 but no luck.

you tested the ones you had as spares, but did not individually test the 
ones already installed. :-(

>
> Any suggestions were to look next??  Oh one other thing I did run 3 
> passes of the memory test on the memory install in the system in case 
> that last 128 Meg memory stick was bad.  I tried the same memory 
> configuration for the Fedora, RH9 and Suse9 install but no luck.

You can identify is it is a bad memory stick by stripping all but one 
stick out, then trying the install.
If it appears to work, then retry with a different stick.
repeat until you have tested all 4 DIMMs or until it fails on one
( If you need to use dual dimms with this dual processor system it 
simply means you become a little more creative to test all the dimms, 
since you would need to test 2 at a time and rotate them until you have 
tried all possible combinations)

FC will install easily with only 128mb of memory, and this will allow 
testing one at a time without guessing where the problem is.

Only after testing all the installed memory should you look at other 
hardware.

memtest86 is another tool that *might* assist in identifying memory 
problems, but is not always 100% correct. (a failure is usually correct, 
but a pass is not always so.)