Boot Problem

I have no real idea. What is your graphic card ?
Was it a fresh install ?

I have been having the same problem with 10.04 LTS.

When I turn the computer on, BIOS and grub do their thing. It doesn't seem to make any difference whether I choose Ubuntu and hit Enter or let grub load it automatically after the 8 second delay (dual boot set up). After the grub boot up screen, the monitor goes to a black screen. I notice a white cursor (like DOS) at the top of the black screen. I monitor the harddisk activity and it seems to start loading the os. Then, at some point, harddisk activity quits and it seems to be hung up. So then I hit Ctrl+Alt+Del, the purple Ubuntu screen comes up for a couple of seconds, and then the computer reboots. On reboot, the os completely loads and everything is fine.

It doesn't do it all of the time and so far I have not been able to establish a pattern. I did a clean install on an Acer Aspire 5100. Since the Ubuntu purple screen shows up and I don't have any other issues with the monitor, I didn't think about the graphics card?

Any help is appreciated.

If you are succesfully boot next time into Ubuntu. Check your hard disk for failure in Palimpsest.

Do you have a black screen with a prompt or nothing ?

Duncan Thomas: In the Disk utility, everything shows that the harddisk is ok; no read write errors.

delance: Every time this problem happens, there is always a black screen with a prompt.

Sorry, my question was incomplete.
Prompt is "_", "grub>" or something else ?

delance: A black screen with a flashing prompt "_" but nothing else before or after the flashing prompt. Loading seems to be hung up at this point - it goes no further, no matter how long I wait.

More info: The hard disk is 120 gig. I wiped the entire disk using active@killdisk. (I wanted a clean disk, hoping this would be my last fresh install.) I used a gparted Live CD to create the MBR and partitons. I didn't create a /boot partition. I installed Ubuntu to /dev/sda1, swap to /dev/sda2, and /home to /dev/sda3. I set /dev/sda4 as an extended partiton for other use.

More info: I used a Ubuntu Live CD for the install. I ran checksum on the .iso file and on the burned CD. Everything checked ok. During install, I only changed what the install windows allowed for, like user info and assigning partitions. I did have the etho network plugged in during install.

More info: I don't know much about log files yet, but I found this in the bootstrap.log and am wondering if this is part or all of the problem.

Selecting previously deselected package base-files.
dpkg: regarding .../base-files_5.0.0ubuntu20_i386.deb containing base-files, pre-dependency problem:
 base-files pre-depends on awk
  awk is not installed.
dpkg: warning: ignoring pre-dependency problem!
(Reading database ... 0 files and directories currently installed.)
Unpacking base-files (from .../base-files_5.0.0ubuntu20_i386.deb) ...
Selecting previously deselected package base-passwd.
Unpacking base-passwd (from .../base-passwd_3.5.22_i386.deb) ...
dpkg: base-passwd: dependency problems, but configuring anyway as you requested:
 base-passwd depends on libc6 (>= 2.8); however:
  Package libc6 is not installed.
Setting up base-passwd (3.5.22) ...

dpkg: base-files: dependency problems, but configuring anyway as you requested:
 base-files depends on awk; however:
  Package awk is not installed.
 base-files depends on libpam-modules (>= 0.79-3ubuntu3); however:
  Package libpam-modules is not installed.
Setting up base-files (5.0.0ubuntu20) ...

dpkg: regarding .../dpkg_1.15.5.6ubuntu4_i386.deb containing dpkg, pre-dependency problem:
 dpkg pre-depends on libc6 (>= 2.11)
dpkg: warning: ignoring pre-dependency problem!
dpkg: regarding .../dpkg_1.15.5.6ubuntu4_i386.deb containing dpkg, pre-dependency problem:
 dpkg pre-depends on coreutils (>= 5.93-1)
dpkg: warning: ignoring pre-dependency problem!
dpkg: regarding .../dpkg_1.15.5.6ubuntu4_i386.deb containing dpkg, pre-dependency problem:
 dpkg pre-depends on lzma
  lzma is not installed.
dpkg: warning: ignoring pre-dependency problem!
(Reading database ... 108 files and directories currently installed.)
Preparing to replace dpkg 1.15.5.6ubuntu4 (using .../dpkg_1.15.5.6ubuntu4_i386.deb) ...
Unpacking replacement dpkg ...
dpkg: dpkg: dependency problems, but configuring anyway as you requested:
 dpkg depends on libc6 (>= 2.11); however:
  Package libc6 is not installed.
 dpkg depends on coreutils (>= 5.93-1); however:
  Package coreutils is not installed.
 dpkg depends on lzma; however:
  Package lzma is not installed.
Setting up dpkg (1.15.5.6ubuntu4) ...

The log continues on with many entries for selecting previously deselected packages and unpacking them. Each entry includes pre-dependency problems and warnings that say "dpkg: warning: ignoring pre-dependency problem!"

This is one of the entries:
Selecting previously deselected package adduser.
(Reading database ... 1471 files and directories currently installed.)
Unpacking adduser (from .../adduser_3.112ubuntu1_all.deb) ...
Preparing to replace base-files 5.0.0ubuntu20 (using .../base-files_5.0.0ubuntu20_i386.deb) ...
Unpacking replacement base-files ...
Preparing to replace base-passwd 3.5.22 (using .../base-passwd_3.5.22_i386.deb) ...
Unpacking replacement base-passwd ...
Selecting previously deselected package bash.
dpkg: regarding .../bash_4.1-2ubuntu3_i386.deb containing bash, pre-dependency problem:
 bash pre-depends on dash
  dash is not installed.
dpkg: warning: ignoring pre-dependency problem!
dpkg: regarding .../bash_4.1-2ubuntu3_i386.deb containing bash, pre-dependency problem:
 bash pre-depends on libncurses5 (>= 5.6+20071006-3)
dpkg: warning: ignoring pre-dependency problem!
Unpacking bash (from .../bash_4.1-2ubuntu3_i386.deb) ...
The bash upgrade discovered that your /bin/sh link points to dash.
As bash for Debian is destined to provide a working /bin/sh (pointing to
/bin/bash) your link will be overwritten by a default link.

I checked with Synaptic and each of the dependencies is installed. Synaptic shows dash and libncurses5 as being installed.

Further down in the log, I found this:
update-rc.d: using dependency based boot sequencing
insserv: warning: script 'network-interface' missing LSB tags and overrides
insserv: warning: script 'plymouth-splash' missing LSB tags and overrides
insserv: warning: script 'hwclock' missing LSB tags and overrides
insserv: warning: script 'procps' missing LSB tags and overrides
insserv: warning: script 'udevmonitor' missing LSB tags and overrides
insserv: warning: script 'hwclock-save' missing LSB tags and overrides
insserv: warning: script 'plymouth-log' missing LSB tags and overrides
insserv: warning: script 'hostname' missing LSB tags and overrides
insserv: warning: script 'udev' missing LSB tags and overrides
insserv: warning: script 'udevtrigger' missing LSB tags and overrides
insserv: warning: script 'plymouth' missing LSB tags and overrides
insserv: warning: script 'module-init-tools' missing LSB tags and overrides
insserv: warning: script 'udev-finish' missing LSB tags and overrides
insserv: warning: script 'plymouth-stop' missing LSB tags and overrides
insserv: warning: script 'network-interface-security' missing LSB tags and overrides

Then the log continues on with ignoring dependency problems and unpacking packages.

Then it goes through a "Setting up ..." packages phase.

Then this:
Warning: Fake initctl called, doing nothing
Removing `local diversion of /sbin/udevadm to /sbin/udevadm.upgrade'
update-initramfs: deferring update (trigger activated)

Then more unpacking and setting up packages. That's the end of the log.

Thanks much for your help.

Did you had issue at first boot after install ?
What is graphic card ? (have a look at https://answers.launchpad.net/grub/+faq/1682 )

Did you had issue at first boot after install ?
No. When the Ubuntu disk ejects, I remove the disk and hit "Enter". When it boots to the fresh install, I let it sit for a few minutes and reboot again. I had no problems at either boot.

 sudo lshw -C display:
  *-display
       description: VGA compatible controller
       product: RS482 [Radeon Xpress 200M]
       vendor: ATI Technologies Inc
       physical id: 5
       bus info: pci@0000:01:05.0
       version: 00
       width: 32 bits
       clock: 66MHz
       capabilities: pm bus_master cap_list rom
       configuration: driver=radeon latency=66 mingnt=8
       resources: irq:17 memory:c0000000-cfffffff(prefetchable) ioport:9000(size=256) memory:b0100000-b010ffff memory:b0120000-b013ffff(prefetchable)

I am going to read the info at the links you supplied tonight.
Thanks.

I started with https://answers.launchpad.net/grub/+faq/1682
and ended up at
https://help.ubuntu.com/community/RadeonDriver
and
https://wiki.ubuntu.com/X/Troubleshooting/FglrxInteferesWithRadeonDriver
and decided to install
xserver-xorg-video-ati

So far, that seems to be working and I have noticed that from BIOS to the Ubuntu purple screen, it is loading faster than before.

I so appreciate and thank you for your help. Until you pointed me to https://answers.launchpad.net/grub/+faq/1682, I had no idea what was causing the problem and never would've thought of the video driver, since it worked well enough the rest of the time. Oh well, live and learn - I try to do every day!

i see in your log:

problem:
 base-files pre-depends on awk
  awk is not installed.

please try to install awk, open a terminal and type:

sudo apt-get install gawk

@marcobra: No. That base-files/awk message is perfectly normal when bootstrapping the system - you have to start somewhere and not all dependencies are satisfied right at the start.

bootstrap.log is almost certainly a complete red herring here.

@Colin Watson, thanks