Ubuntu 9.04 comes with some visual effects from Compiz turned on by default. This post contains a list of the key combo’s used to active some of them. Compiz also offers many other “cool” effects. If you install the compizconfig settings manager you can enable/disable all of the neat effects (most of which are eye-candy, and not really useful).
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Following the directions on Lars’ blog, I set up an encrypted home directory on Ubuntu 9.04 using LUKS.
The following commands were all executed with root permissions. Add “sudo” to the front of the commands if you are not running with root permissions. Continue reading
Installing Ubuntu 9.04 (Jaunty) on an Acer Aspire One (Model D150) worked quite well. I had to use an external USB CD-Rom Drive as the Aspire One does not have a built in drive, but after enabling the “Press F12 to choose boot device” menu in the system BIOS I was able to boot off of the external USB CD-Rom drive.
Ubuntu worked well with all the major hardware (video, wifi,wired-ethernet, soundcard, and webcam) and the only hiccup was with the built in microphone, which did not work out of the box (the microphone jack would work, just not the built in microphone.)
To get the built in microphone working, I had to install the latest version of the ALSA driver following the instructions I found in post 28 on this thread, as copied below:
So I downloaded alsa-driver-1.0.20.tar.bz2 from
http://www.alsa-project.org/main/index.php/Main_Page
I unzipped the package, I entered into the main directory of the package and then I typed:
sudo apt-get install build-essential ncurses-dev
./configure –with-cards=hda-intel
make
sudo make installThen I edited /etc/modprobe.d/alsa-base.conf and I added at the end of file the line:
options snd-hda-intel model=acer-aspireAfter the reboot I adjusted the audio preferences in this way:
Device: HDA Intel (Alsa mixer)
Preferences: The first 3 items and last 2 items (Front Mic is disabled!!!)
Input Sources is set as default at Mic (not Front Mic!!!).Finally check that System->Preferences->Sound->Sound Capture is set to “HDA Intel ALC272 Analog(ALSA)” not “ALSA”
My SiliconDust HD HomeRun has a relatively good HD tuner, but it’s not quite as good as the built in tuner on my TV at picking up stations that are extremely strong and have multi-path reception problems. Although the signal My MythTV box reception of Fox TV would intermittently cut out as the SNR would drop too low to enable reception (even though, or, because the power level was pegged at 100%).
I purchased a Skywalker 16db attenuator, and it successfully lowered the signal strength of the (overpowered) Fox channel so that my HD HomeRun’s tuner chip could receive it with an acceptable SNR and no dropouts.
The only problem with attenuating my signal was that one of the two PBS channels (8, GPB-HD) was too weak to be picked up through the attenuator.
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I upgraded to Ubuntu 9.04 from 8.10 over the weekend.
The good:
Faster boot up. (worth the upgrade all by itself)
New notification “bubbles” that appear and then disappear again without any fuss.
OpenOffice 3.0 and other software upgrades.
The Bad:
Required tweaks to my pam_mount.conf.xml file to get my encrypted home directory to work. (Not an issue for most users.)
Bluetooth communication ports (serial over bluetooth) started giving errors because standard users no longer had permissions to use them. Adding the following code to an /etc/udev/rules.d/rfcomm.rules file allowed all users in the “dialout” group to access the /dev/rfcommXXX serial over bluetooth ports. (Ubuntu developers know about this problem and it will be fixed eventually.)
KERNEL=="rfcomm*", GROUP="dialout"
Java support for MIDI music failed until I installed timidity again with the following command:
sudo apt-get install timidity pmidi
The Annoying:
The hardware buttons on my thinkpad (brightness, volume, etc) still work, but no longer have an on screen display. I could fix this by installing the tpb (thinkPadButtons) package, but it takes up extra CPU cycles and power. I found that the packagers are actively discussing this issue and have decided to wait until they fix the issue within the default packages.
When running Pidgin (IM client), an “envelope” icon appears inside a “indicator-applet 0.1” to show that it’s running. Of course, Pidgin itself pops up another icon to show that it’s running on my gnome panel at the same time. I’ve thought about removing the indicator-applet from my panel to remove the duplicate items, but worried about what else I may miss if it’s not there to “hold all of the system indicators”. I eventually decided to go into the Pidgin preferences and select “Show System Tray Icon” only “on unread messages” which mostly fixed this annoyance, although now I need two button clicks to bring the IM window to the top instead of just one.
The ATI M6 graphics processor on my IBM X31 laptop was not automatically configured to use hardware acceleration. To use ppracer and other applications that require hardware acelleration to work well (such as the new version of lyx!) I had to edit my xorg.conf file following directions I found here.
One of the claimed features that made me upgrade to Ubuntu 9.04 was the boot-up speed increases. Before the upgrade using Ubuntu 8.10 it took my computer 55 seconds to boot up to the login screen. Including a very fast (2 second) login, it took 1:25 until the desktop was “usable”. Starting Thunderbird and Firefox immediately took until 1:55 to bring up both windows.
After I installed Ubuntu 9.04 I timed the login. I was impressed with the speed increases. It took
35 seconds to get to the login screen. Including a very fast (2 second) login, it took 1:05 until the desktop was “usable”. Starting up both Thunderbird and Firefox were ready to use by one minute and thirty seconds after bootup.
The bootup time of Ubuntu 9.04 is identical to that of Windows Vista (the shutdown time is approximately 5 seconds faster)
I just used the distribution upgrade option to move from Ubuntu 8.10 to 9.04. My dm-crypt encrypted home directory initially refused to load, and I had to change my volume entry in the /etc/security/pam_mount.conf.xml to make it work again.
Specifically, a few of the defaults had changed, so now I had to specify the old (8.04) defaults (ripemd160 hash).
< volume user="summetj" fstype="crypt" path="/dev/sda6" mountpoint="/home/summetj" options="cipher=aes,hash=ripemd160,fsk_cipher=aes-256-ecb,fsk_hash=md5" keyfile="/home/summetj.key" / >
When I set up my MythTV box to suspend itself (and wake up whenever a show needed to be recorded) I followed the directions on the MythWiki ACPI Wakeup page, which suggested that I disable writes to the hardware clock as follows:
“Disable hwclock updates
On most machines it’s required to make a small change to the Linux shutdown procedure. When your machine goes down, most linux distributions write the system time/data back to the bios. On MANY machines, the machine never wakes-up after a time/data update. It’s recommended to make this change before you start. See below for more details (distro specific),
The reason for the recommendation above is that most linux distributions write the current system time back to the bios when shutting down the machine, and with some BIOSes, the machine will not wake up if the hardware clock is modified after the alarm timer has been set. To avoid that, it is necessary to disable the writing of the current system time to the hardware clock in the system shutdown scripts.”
This had no negative effects until daylight savings time kicked in. My MythTV box syncs itself over the internet, so it updated itself to daylight savings time with no problems. However, the system BIOS clock (hwclock) was not updated because I had disabled hardware clock updates! After a week of recording the very ends of shows instead of the full shows, I figured out what was happening and issued a “hwclock –systohc” command to re-set the BIOS (hardware) clock from the (correct) system time.
However, this will only work until daylight savings time ends, so I am investigating if I really need to disable the write to my hardware clock after the system sets the wakeup time. It may be that my BIOS handles that correctly, in which case I can take out the “HWCLOCKACCESS=no” line I added to my “/etc/default/rcS” file.
Searching and replacing a bit of text in a lot of files is a very common problem. Lots of tools exist to get it done. On unix systems, awk is one favorite, and I found this webpage with a simple search and replace example.
Unfortunately, I wanted to search for \prob and replace it with %\prob. The difficulty is that the backslash character is “special”, so you have to escape it with other backslashes.
Here is my updated example command to run in each directory:
awk ‘{gsub(/\\prob/,”%\\prob”, $0); print > FILENAME}’ *.tex
It does a global substitution for the regex \\prob with string %\prob in the
whole input file ($0) for every file that ends in .tex
My encrypted home directory worked well with 8.04, I only had to make one change caused by the new xml format of the pam_mount.conf.xml file as follows:
<volume user="summetj" fstype="crypt" path="/dev/sda6" mountpoint="/home/summetj" options="cipher=aes" fskeycipher="aes-256-ecb" fskeypath="/home/summetj.key" />
After I installed 8.04 from scratch I had to mount the directory and chown the files to the new user.