Linux Blog

The root for the previously installed system was not found – Fedora

Filed under: General Linux,Linux Software — TheLinuxBlog.com at 12:30 am on Wednesday, January 12, 2011

The root for the previously installed system was not found
I was having an issue with a preupgrade of Fedora, somehow an old package that was no longer in use decided it was going to cause the installation to fail. After rebooting, finding the guilty package and removing it I started the upgrade again. This is where the error message “The root for the previously installed system was not found” occurred.

I did some research, tried mounting the file system then upgrading that way and still nothing.

According to this Fedora Forums post other people have experienced this issue. In cagonto1980′s post it explains the workaround:
Mount the filesystem, vi /mnt/sysimage/etc/fedora-release and change the release to the previous version. You may need to remember the version, mine was set to “Fedora 13 (Goddard)” and I changed it to “Fedora 12 (Constantine)”. After rebooting it started the upgrade. It appears the issue is Anaconda updates the release file and doesn’t change it back if the installation fails causing the next upgrade to think that the newest version is installed.

Thanks to cagonto1980 for the workaround.

Add Voice to your Shell Scripts

Filed under: Shell Script Sundays — TheLinuxBlog.com at 3:52 pm on Sunday, October 12, 2008

Text to speech has been around for a number of years. While you may not want to add text to speech to all of your shell scripts you may have a particular script that would be nice to get some audio feedback from. There are a couple of text-to-speech engines that run in the shell, but my favorite is flite. It is really simple to install and use and has a decent set of voices. You can add other voices or compile your own with FestVox.

Here is how to use flite from the shell to directly play the text:

[owen@TheLinuxBlog ~]$ flite -t "Thanks for reading The Linochs Blog"

Notice the misspelling of the word Linux. If flite doesn’t correctly output the words, you can sometimes use phonetics to get a better result.

You can also play text files by using the -f option.

[owen@TheLinuxBlog ~]$ flite -t "Thanks for reading The Linochs Blog"
flite: pcm_params.c:2333: sndrv_pcm_hw_params: Assertion `err >= 0' failed.

(Read on …)

Bash Aliases

Filed under: General Linux,Linux Software,Quick Linux Tutorials — TheLinuxBlog.com at 12:23 pm on Wednesday, June 25, 2008

Have you ever wanted to make a command for something that did not exist? Perhaps modify the functionality of a particular application to something more suitable? I know I have. For example, and I know that there is probably a better way to do this, but on certain Linux machines (such as servers), I like to clear the output before exiting. While I can type the command:

 clear; exit

this still leaves me with a line at the top of the screen. Some distributions clear this automatically, for those that don’t an alias can be used.The basic principal for a bash alias is easy. You set an alias up and then use that alias instead of the command.
It appears that aliases have precedence over any already existing applications in the path so it becomes handy if you wish to override a command or perform a task before launching a built in command. I’m sure that this option can be changed if needed.

Now you know what aliases are here is how to use an alias to override the exit command in bash.

alias exit="clear; exit > /dev/null 2&> /dev/null"

Aliases with parameters can get tricky, the best workaround I have found is to write a shell script and put it in your local bin directory.