Difference between revisions of "COMP 3000 Lab 4 2010"

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# Add a new grub menu item which limits the standard kernel to 256M.
# Add a new grub menu item which limits the standard kernel to 256M.
# Add a second virtual disk and make it bootable: put the kernel and initial ram disk on it and then install grub.  Can you boot off of this disk?  What does it do?   
# Add a second virtual disk and make it bootable: put the kernel and initial ram disk on it and then install grub.  Can you boot off of this disk?  What does it do?   
# Mount the standard kernel's initial ram disk (initrd).  What program is first run in this environment?  What does it do?
# Examine the standard kernel's initial ram disk (initrd).  What program is first run in this environment?  What does it do?
# What programs does upstart start on boot?
# What programs does upstart start on boot?


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===Kernel command line options===
===Kernel command line options===


===GRUB configuration===


===GRUB configuration===
*On Ubuntu the user configuration is stored in /etc/default/grub.  The main grub files are stored in /boot/grub.  You can update grub's config with the update-grub command.


===How GRUB works===
===How GRUB works===


===mounting RAM disks===
===Examining RAM disks===
 
*You'll need to use a loopback mount: mount -o loop <device> <mountpoint>


*Ubuntu (Debian) store initial RAM disks in the cpio format.  'zcat <file> | cpio -i' will extract its contents.


===Upstart/init===
===Upstart/init===

Revision as of 12:11, 1 November 2010

All of the following should be done with an Ubuntu 10.04 distribution or equivalent. We recommend experimenting in a virtual environment because some of the exercises could make your system unbootable. (In fact, take a snapshot of your working system before starting these exercises so you can easily revert.)

Questions

  1. Change the grub command line at boot to limit the total available RAM to 256M. You'll need to get to select an entry and edit it from within grub.
  2. Add a new grub menu item which limits the standard kernel to 256M.
  3. Add a second virtual disk and make it bootable: put the kernel and initial ram disk on it and then install grub. Can you boot off of this disk? What does it do?
  4. Examine the standard kernel's initial ram disk (initrd). What program is first run in this environment? What does it do?
  5. What programs does upstart start on boot?

Hints

Please add your hints below to help your fellow students!

Kernel command line options

GRUB configuration

  • On Ubuntu the user configuration is stored in /etc/default/grub. The main grub files are stored in /boot/grub. You can update grub's config with the update-grub command.

How GRUB works

Examining RAM disks

  • Ubuntu (Debian) store initial RAM disks in the cpio format. 'zcat <file> | cpio -i' will extract its contents.

Upstart/init