how to check folder/directory capacity in linux

NAME
du – estimate file space usage
SYNOPSIS
du [OPTION]… [FILE]…
DESCRIPTION
Summarize disk usage of each FILE, recursively for directories.
Mandatory arguments to long options are mandatory for short options too.
-a, –all
write counts for all files, not just directories
-B, –block-size=SIZE use SIZE-byte blocks
-b, –bytes
print size in bytes
-c, –total
produce a grand total
-D, –dereference-args
dereference FILEs that are symbolic links
-h, –human-readable
print sizes in [...]

Add proxy Ubuntu 9.10

Also known as : err (22 : invalid argument)
vim ~/.bashrc
add this line at the bottom
export http_proxy=http://domain.com:port

How to reset root Password Ubuntu & Fedora

Lost your root password?

If you have lost your root password, you can’t really recover it, but you can change it if you have physical access to the machine.

The two most used methods of changing your root password if it’s lost is:
Booting into single-user mode and resetting the password
Booting from a live CD and [...]

Error cannot retrieve repository metadata repomd.xml for repository

You need to edit two of your repository files: /etc/yum.repos.d/fedora.repo and /etc/yum.repos.d/fedora-updates.repo. Now un-comment all the lines that start with the term baseurl and place a comment before all lines that start with mirrorlist. This should be done for both the above files.
Now edit your /etc/hosts file and append the following to it’s contents:
80.239.156.215 [...]

Recover Lost Data / Partitions

TestDisk is a powerful free data recovery software! It was primarily designed to help recover lost partitions and/or make non-booting disks bootable again when these symptoms are caused by faulty software, certain types of viruses or human error (such as accidentally deleting a Partition Table). Partition table recovery using TestDisk is really easy. (read more…)