MondoRescue HOWTO: Utilisation and Configuration of Mondo and Mindi under Linux (Version 2.2.1-rRRR)
| Chapter 10. FAQ |

# 10.3. Booting and Kernel related Questions

10.3.1. Q: When I try to boot from the Mondo CD, it says, "VFS: Unable to mount root fs." I am using an old Debian distro. What do I do?
10.3.2. Q: When I try to boot from the Mondo CD, it says, "Cannot mount root fs - kernel panic," or something similar. What do I do?
10.3.3. Q: When I try to boot from the Mondo CD, it says, "UPGRADE YOUR RAM". What does that mean?
10.3.4. Q: When I try to boot from the Mondo CD, it says something about not finding my CD-ROM drive and then it blames the kernel. What does that mean?
10.3.5. Q: The Mondo CD/floppy takes ages to boot. How can I speed it up?
10.3.6. Q: I made a Mondo CD using the failsafe kernel (i.e. I said 'no' when Mondo asked if I wanted to use my own kernel). It still doesn't boot. Help!
10.3.7. Q: What if my PC won't boot from a CD?
10.3.8. Q: But why won't Mondo boot from my CD? It says my kernel is flawed/outdated/ whatever, and when I wrote to the ML, they told me the same thing... but I still don't get it. I mean, my kernel works for everything else. Why not Mondo?
10.3.9. Q: Why do I only need a boot disk if I'm using a tape drive? Where are the data disks?
10.3.10. Q: Why does it say, "Process accounting FAILED" when I reboot?
10.3.11. Q: Why does it say, &#8220;request_module[block-major-1]: Root fs not mounted VFS: Cannot open root device "100" or 01:00 Please append a correct "root=" boot option kernel panic: VFS: Unable to mount root fs on 01:00&#8221; when i boot from the CD?
10.3.12. Q: How do i copy boot+data disk images to physical floppy disks ?
10.3.13. Q: My tape drive doesn't play nicely with Mondo at boot-time. What do I do?

10.3.1. Q: When I try to boot from the Mondo CD, it says, "VFS: Unable to mount root fs." I am using an old Debian distro. What do I do?

A: Ask Debian's designers why they, unlike every other distro I can find, have included cramfs and other 'goodies' with their kernel. In the meantime, please use '-k FAILSAFE' in your command line when calling Mondo.

A: From Sarge onwards, all stock Debian 2.6 kernels should work fine. If you are still using stock Debian 2.4 kernels, FAILSAFE is the way to go. Of course, if you have compiled your own kernel and experience problems, FAILSAFE is the way to go as well, but this is not really Debian-specific.

10.3.2. Q: When I try to boot from the Mondo CD, it says, "Cannot mount root fs - kernel panic," or something similar. What do I do?

A: Recompile your kernel (or use '-k FAILSAFE'). Take a look at Linux Kernel support to see what you're kernel must support.

10.3.3. Q: When I try to boot from the Mondo CD, it says, "UPGRADE YOUR RAM". What does that mean?

A: Recompile your kernel and add Virtual memory file system support. Take a look at Linux Kernel support to see what you're kernel must support. (Of course, if your PC has less than 64MB of RAM, you could always... what's the phrase? I know, upgrade your RAM!)

10.3.4. Q: When I try to boot from the Mondo CD, it says something about not finding my CD-ROM drive and then it blames the kernel. What does that mean?

A: Your kernel must support initrd, loopfs, IDE|SCSI|USB CD-ROM's, and ramdisks. Take a look at Linux Kernel support to see what you're kernel must support. If your kernel does not support these things, Mondo will not boot from your CD. However, when running Mindi, you may choose to use _its_ kernel instead of your own. In addition, you may boot from floppy disk images instead the CD: copy the disk images from the CD /images directory to floppy disks, using 'dd'. Take a look at Copy boot data disks on how to make those.

10.3.5. Q: The Mondo CD/floppy takes ages to boot. How can I speed it up?

A: Edit mindi (it's a shell script, btw) and change LILO_OPTIONS="" to LILO_OPTIONS="-c". This enables map compaction in lilo and speeds up booting, for more info see the lilo man page.

10.3.6. Q: I made a Mondo CD using the failsafe kernel (i.e. I said 'no' when Mondo asked if I wanted to use my own kernel). It still doesn't boot. Help!

A: OK, now that is a bug. :-) I included a kernel with Mondo (technically, with Mindi, which Mondo uses) to make sure that users could use Mondo despite flaws in their own kernels. If you are using Mondo/Mindi's kernel but still cannot boot from your Mondo CD then please e-mail the mondorescue mailing list.

10.3.7. Q: What if my PC won't boot from a CD?

A: Copy the image files from the CD /images directory, using the dd command. Take a look at Copy boot data disks on how to make those. Then boot from the first floppy; follow it up with the data disks; finally, type 'mount /mnt/cdrom' and then utilize the restore script as usual, e.g. mondorestore.

A: You may also want to boot using the network with PXE. Look at the README.pxe file of mindi to know more details on how.

10.3.8. Q: But why won't Mondo boot from my CD? It says my kernel is flawed/outdated/ whatever, and when I wrote to the ML, they told me the same thing... but I still don't get it. I mean, my kernel works for everything else. Why not Mondo?

A: Because Mondo makes a boot disk using your kernel. I bet your other software doesn't do that. Also, not all kernels are suitable for boot disks. I'm sorry but that's Life. Upgrade your kernel and/or recompile it. Take a look at Linux Kernel support to see what you're kernel must support.

10.3.9. Q: Why do I only need a boot disk if I'm using a tape drive? Where are the data disks?

A: On the tape. :-) The first 32MB of the tape will be set aside for a large tarball containing the data disks, a list of all files backed up, and other sundries. If Mondo and Mindi do their respective jobs then you won't need additional floppies, just the boot floppy and the tape(s).

For the moment mondorescue doesn't support OBDR for tapes. Feel free to produce patches for it :-)

10.3.10. Q: Why does it say, "Process accounting FAILED" when I reboot?

A: You were using Process Accounting. Red Hat (or whichever distro you are using) does not provide a startup/shutdown script yet. So, when you try to backup the process log, it just grows and grows as Mondo tries to back it up. Mondo doesn't back it up anymore and that's why. The unfortunate side-effect is... well, what you see on your screen. Type 'touch /var/log/pacct' and then 'paccton' to fix the error message.

10.3.11. Q: Why does it say, &#8220;request_module[block-major-1]: Root fs not mounted VFS: Cannot open root device "100" or 01:00 Please append a correct "root=" boot option kernel panic: VFS: Unable to mount root fs on 01:00&#8221; when i boot from the CD?

A: Recompile your kernel and add initrd support. Take a look at Linux Kernel supportto see what you're kernel must support.

10.3.12. Q: How do i copy boot+data disk images to physical floppy disks ?

A: The images are in /root/images/mindi (even if they are created by Mondo) and also in the 'images' directory on the first CD of your backup set, if you have backed up to CD. You can copy the images to disk as follows:-

Put an empty Boot floppy
bash# fdformat /dev/fd0u1722
bash# dd if=/root/images/mindi/mindi-boot.1722.img of=/dev/fd0u1722
Put an empty Data floppy
bash# fdformat /dev/fd0
bash# dd if=/root/images/mindi/mindi-data-N.img of=/dev/fd0
Replace N with 1, 2, etc.

10.3.13. Q: My tape drive doesn't play nicely with Mondo at boot-time. What do I do?

A: Play with 'mt'. Use its setblksize and defblksize switches to reconfigure your tape drive if necessary. Some tape drives just are painful. If yours is one of them then God help you. Mondo can handle any tape drive whose drive and firmware can handle fopen(), fwrite(), fread() and fclose(). Mondo uses standard C libraries to talk to your tape streamer. If your tape streamer can't handle that then you had better call a priest. Either that or ask for a refund.

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