Mar
17
Quick Fix for the ‘Size Mismatch’ When Updating Ubuntu Linux
March 17, 2009 | By: UbuntuLinuxHelp | 2 Comments
Posted in How To
This is just a short "quick fix" post.
For those who need it, here's a quick fix when you get an error message like this:
"W: Failed to fetch http://security.ubuntu.com/ubuntu/pool/main/f/ffmpeg/libpostproc1d_0.cvs20070307-5ubuntu7.2_amd64.deb Size mismatch"
It's an error I received when the auto update feature was working in Ubuntu Linux. I double checked my sources.list file, but it was okay.
After a bit of tinkering, here's how to fix that.
Open a terminal and enter the following command:
sudo aptitude clean
And then:
sudo aptitude update
After this the updates re-downloaded and everything worked. If you prefer "apt-get" you can substitute it in place of the "aptitude" command.
The logic behind this was that perhaps the downloaded files themselves, were corrupt. If they are already in the local repository, they will not download again. Hence the "clean" option. "Clean" empties the local repository of downloaded packages (but it does not delete the lock file). Using the clean option occasionally can be helpful in conserving disk space.
The second command that featured the "update" option, resynchronized the package files from their sources. This means that the .gz files (at the source) were scanned for new and updated information - if any is available. When making changes to the sources.list file, this command (update) should be run before doing any upgrading.
Hope this helps some of you out there! :)
Mar
16
Build a Web Developer PC and Enable Most Media Playback Using Ubuntu Linux
March 16, 2009 | By: UbuntuLinuxHelp | 13 Comments
Posted in Applications, Hands On, How To
For those of you who follow my other blog, you'll know that my last Windows PC had a major failure again. You can read some of the specifics in the "When Disaster Strikes - Again" post. At that point I decided to install Ubuntu (effectively removing Windows based PC's from the network).
In some ways I was bothered about this. Why? I work best with Illustrator, Photoshop, After Effects, Dreamweaver, WinSCP, Flash and so on. I felt like I was going to lose all the productivity these applications provided. I enjoy being able to double click media and play it automatically, same goes with DVD movies, etc. In Linux, I've often encountered problems with media playback as the media usually includes restricted formats, MP3 for example. On the developer/designer side, I was not looking forward (nor do I have time) to a steep learning curve.
This post (hopefully) will show the desktop user how to enable all the restricted media playbacks (movie DVD, music MP3, etc.)
It will also show web developers and designers some of the issues, applications and work arounds - Or at least the current state of them.
First off, let's deal with the media issues. I built this PC using Ubuntu 8.04 LTS 64Bit (Hardy). I did Read more
Mar
13
Quick Fix: Black Desktop Background and Lost Icons
March 13, 2009 | By: UbuntuLinuxHelp | 24 Comments
Posted in How To
Just a short post for any of you that encounter the same issue I just did. I booted up this morning (Ubuntu Linux 8.04 - Hardy) and logged in, no problem. But my desktop background image (the wallpaper) had disappeared, along with my desktop icons. Also, the desktop background was all black. Rebooting did not fix the issue.
At first I thought it might be the nVidia drivers, but that was not correct because everything else worked (looked) fine. I did notice that if I right clicked on the desktop, nothing happened - No menu, no pop-up. If I selected System -> Preferences -> Appearance and then the Background tab, I was able to add and select several backgrounds but they did not display on the desktop (it remained back).
The issue turned out to be with Read more
Mar
11
Linux in 30 Days
March 11, 2009 | By: UbuntuLinuxHelp | 5 Comments
Posted in Editorials
Some time ago, one of our readers (Jon Donovan) suggested a blog in which visitors could take a 30 challenge and post their thoughts, comments, observations and so on, about various Linux distributions. As a result, a "child site" was born! LinuxIn30Days.com
We've since started fielding requests from other readers, that in many respects mirror the purpose of "Linux in 30 Day". For those interested, please take a look at the new blog, and if you'd be kind enough, please do provide input!
While the focus was originally geared towards the new Linux user, I thought it would be more effective to have ANY user provide input about different Linux installs. I also think a new design may be more effective? (What do you think?) - Don't get me wrong, I'm still happy when you want to contribute to this blog, however know there are two options: Read more
Mar
9
Getting Started with Firewall Builder
March 9, 2009 | By: Vadim Kurland | 4 Comments
Posted in Hands On, How To
This guide presents an introduction to Firewall Builder. Firewall Builder (also known as fwbuilder), is a GUI firewall configuration and management tool that supports iptables (netfilter), ipfilter, pf, ipfw, Cisco PIX (FWSM, ASA) and Cisco routers extended access lists. Both professional network administrators and hobbyists managing firewalls with policies more complex that is allowed by simple web based UI can simplify management tasks with the application. The program runs on Linux, FreeBSD, OpenBSD, Windows and Mac OS X and can manage both local and remote firewalls.
Firewall Builder is packaged with most Linux distributions and is available under "System/Administration" menu.
Accessing Firewall Builder
If it is not there, then it probably needs to be installed on your system. You need to install the package that has supporting the API library libfwbuilder and the package for fwbuilder that contains the Firewall Builder GUI and policy compilers. Use apt-get or aptitude to find and Read more
