How to Undo an Update in Ubuntu Lucid

Well it took me a few hours but I finally figured out why a couple of the images I've been working on were taking so long to fully load the Gnome Panel upon login (about 30 seconds as opposed to the 5-8 it normally takes). After ruling out dozens of other possibilities I finally realized that it was a gnome-keyring update I installed just today that was causing the panel to load so slowly. It wasn't easy though.

The first step to undoing the offending update was to find out what updates it was exactly. After searching some forums I came across a way to see my update history:

• Open synaptic package manager ("sudo synaptic" in the terminal). From the menu bar, click File -> History and you will see all your updates sorted by date.

Unfortunately I had installed about 20 updates today, and I didn't know which one had caused the problem. By searching through each of the packages named in the History list, I was able to downgrade a few at a time until the problem was solved and I had identified the offending update. To do this:

• Use the search bar to find the package you want to downgrade. Once you've found what you're looking for, click on the package to select it. From the menu bar, click Package -> Force Version and select the previous version of the package from the drop down menu. Click the "Apply" button to apply the downgrade.

It's not an elegant solution, but it did the trick for me. Hopefully it will help someone else out there sometime too. Cheers! -Joe

Lock Down Firefox Preferences on Ubuntu Lucid With a New firefox.js File

In the past couple of weeks we've received 105 donated computers. Dell GX260/270 towers, P4's all, 512MB-1GB of RAM and decent specs otherwise. This has dramatically shifted my vision for the technology infrastructure of the Academies. We no longer have to worry about utilizing underpowered Pentium 3 machines any longer, which means the need for LTSP and all its advantages is gone as well.

LTSP is, in my opinion, an elegant but troublesome solution. Without consistent and frequent monitoring there are simply too many ways for individual workstations to stop functioning. Of course, when a breaker flips, a student accidentally kicks a surge protector strip off, or someone knocks out the switch the whole thing comes to a crashing halt.

Therefore, I've recently begun building several images of both Windows XP (for our Rosetta Stone utilizing teachers) and Ubuntu Lucid for the various machines we have on campus. I'm hoping to find the time to put together a complete "From Square One" guide to locking down the Ubuntu desktop (as I've done it a few times already this week), but for now I thought I'd share a particularly useful bit of code, following up from a previous post of mine.

Some of the old firefox.js settings no longer work, but I've managed to fix all of them and add a couple more that I like. I think the descriptions are mostly adequate to see what I'm attempting, but if you have any questions drop a comment and I'll reply. Cheers! -Joe

As before, this is the firefox.js file located in etc/firefox/pref/

// This is the Debian specific preferences file for Mozilla Firefox
// You can make any change in here, it is the purpose of this file.
// You can, with this file and all files present in the
// /etc/firefox/pref directory, override any preference that is
// present in /usr/lib/firefox/defaults/pref directory.
// While your changes will be kept on upgrade if you modify files in
// /etc/firefox/pref, please note that they won't be kept if you
// do them in /usr/lib/firefox/defaults/pref.

pref("extensions.update.enabled", true);

// Use LANG environment variable to choose locale
pref("intl.locale.matchOS", true);

// Disable default browser checking.
pref("browser.shell.checkDefaultBrowser", false);

// Prevent EULA dialog to popup on first run
pref("browser.EULA.override", true);

// identify default locale to use if no /usr/lib/firefox-addons/searchplugins/LOCALE
// exists for the current used LOCALE
pref("distribution.searchplugins.defaultLocale", "en-US");

// Enable the NetworkManager integration
pref("toolkit.networkmanager.disable", false);

// Other preferences

user_pref("browser.startup.homepage", "http://www.aeacs.org");

user_pref("startup.homepage_override_url", "http://www.aeacs.org");

user_pref("startup.homepage_welcome_url", "http://www.aeacs.org");

pref("browser.startup.homepage_reset", "http://www.aeacs.org");

pref("privacy.sanitize.sanitizeOnShutdown", true);

pref("privacy.sanitize.promptOnSanitize", false);

pref("privacy.clearOnShutdown.offlineApps", true);

pref("privacy.clearOnShutdown.passwords", true);

pref("privacy.clearOnShutdown.siteSettings", true);

pref("privacy.clearOnShutdown.history", false);

pref("privacy.clearOnShutdown.downloads", false);

pref("signon.rememberSignons", false);

pref("browser.tabs.warnOnClose", false);