Saltycrane logo

SaltyCrane Blog

Notes on Python, Django, and web development on Ubuntu Linux

    

Ubuntu notes

Date: 2009-03-25  |   Modified: 2010-07-06  |   Tags: notestoself, ubuntu

Boot process

  • What are the stages of the boot process?
    1. BIOS
    2. Master Boot Record
    3. Bootloader (LILO, GRUB)
    4. Kernel
    5. init
    6. Run Levels

  • Where is the GRUB menu list?
    /boot/grub/menu.lst

  • How do I get rid of Ubuntu splash screen / progress bar and show scrolling text?
    Remove quiet and splash from "kernel" line in /boot/grub/menu.lst

See also:
http://en.wikipedia.org/wiki/Linux_startup_process
http://www.debianhelp.co.uk/boot.htm

Run levels

  • What are the run levels for Ubuntu?
    1: single user
    2: default
    3-5: same as 2
    6: reboot

  • Where can I find the default startup programs for run level 2?
    /etc/rc2.d

  • How do I update the symbolic links in /etc/rc?.d?
    Use update-rc.d. For help, man update-rc.d.

  • Where is the default run level set in Ubuntu?
    /etc/event.d/rc-default

Xsessions

  • Where is another location for startup programs?
    /etc/X11/Xsession.d

Restarting

  • What are some alternatives to rebooting?
    1. Restart the display manager, gdm
      sudo /etc/init.d/gdm restart or CTRL+ALT+BACKSPACE
    2. Switch to runlevel 1 then back to runlevel 2
      sudo telinit 1 then telinit 2 (this didn't work for me; I wasn't able to get to runlevel 1.)
    3. This article has a lot of good tips including Alt+SysReq+"Raising Skinny Elephants Is Utterly Boring" - http://www.linuxclues.com/articles/09.htm

  • How can I reboot?
    reboot or CTRL+ALT+DEL

Keeping Ubuntu time up to date

I would think Ubuntu would install something to keep the system clock from drifting, but it seems they haven't. There are at least 2 options: ntpdate and ntpd. Ntpdate is used from a cron script to sync the time once a day. Ntpd runs as a daemon and ajusts the time continually but it costs resources. On my machine, using ps -e -O rss | grep ntpd, I got 1.3 MB of memory use. Here is how to install ntpd: 

sudo apt-get install ntp

The ntp config file is located at: /etc/ntp.conf

Reference: https://help.ubuntu.com/9.04/serverguide/C/NTP.html

My /etc/apt/sources.list

This sources.list includes security, updates, and proposed (but not backports) and source for the main, restricted, universe, and multiverse repositories.

deb http://archive.ubuntu.com/ubuntu/ jaunty main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ jaunty main restricted universe multiverse

deb http://archive.ubuntu.com/ubuntu/ jaunty-security main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ jaunty-security main restricted universe multiverse

deb http://archive.ubuntu.com/ubuntu/ jaunty-updates restricted main universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ jaunty-updates restricted main universe multiverse

deb http://archive.ubuntu.com/ubuntu/ jaunty-proposed restricted main multiverse universe
deb-src http://archive.ubuntu.com/ubuntu/ jaunty-proposed restricted main multiverse universe

My filesystem changes

  • For wmii: 
    sudo ln -s /usr/include/freetype2/freetype /usr/include/freetype

System config file changes:

These changes apply to Ubuntu Karmic

  • Disable xsplash before session load: Comment out the following from /etc/gdm/PreSession/Default: 
    if [ -x '/usr/bin/xsplash' ];
then
        /usr/bin/xsplash --daemon
fi
  • To run ~/.xsession from gdm: Create a '.desktop' file in '/usr/share/xsessions' [owned by root:root with permissions 644] whose 'Exec' entry is '/etc/X11/Xsession'.

How to show what you've installed with apt-get

Haven't found a way that I'm happy with yet. Here are some options:

  • sudo apt-get install apt-show-versions
apt-show-versions
  • dpkg --get-selections

Sound troubleshooting

  • Make sure speakers are plugged in / power strip on. (For some reason, the power to my speakers keeps going out.
  • Run gnome-volume-control. Make sure volume is up and not muted. (For some reason on Karmic this resets to mute on restart.)

Skype microphone troubleshooting

Running Skype 2.1.0.47-1 on Ubuntu Karmic

  • Run gnome-volume-control. Select Microphone 1. Raise the volume up to almost Max.
  • (Testing can be done with gnome-sound-recorder.)

Flash

Emacs keybindings

Copy /usr/share/themes/Emacs/gtk-2.0-key/gtkrc to ~/.gtkrc-2.0. Edit as necessary.

(Hardware) System Information

sudo apt-get install sysinfo

custom xsession

Edit /usr/share/xsessions/user.desktop

[Desktop Entry]
Name=~/.xsession
Comment=User's .xsession
Exec=/etc/X11/Xsession
TryExec=/etc/X11/Xsession
Icon=
Type=Application

Post a comment
Required
Required, but not displayed
Optional

Format using Markdown. (No HTML.)
  • Code blocks: prefix each line by at least 4 spaces or 1 tab (and a blank line before and after)
  • Code span: surround with backticks
  • Blockquotes: prefix lines to be quoted with >
  • Links: <URL>
  • Links w/ description: [description](URL)
Created with Django | Hosted by Slicehost