Ask Ubuntu is a question and answer site for Ubuntu users and developers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I'm using Ubuntu 11.04 and I want to free up some space in my root directory, which is overloaded. I especially want to change the path used for installing applications (they are getting installed directly to the root drive).

Another consideration is that I'm working on a MySQL database server. The server is installed in the root directory itself, so I don't want to risk losing any data.

Please give me some tips to help sort out this problem.

share|improve this question

10 Answers 10

Recently I faced similar situation. Too many applications got installed and they started using my root mount space. I am listing out few steps which I followed and hoping that you could also use the same.

  1. Clean apt-get cache. Following command will remove all downloaded deb files from apt-get cache directory.

    Run this command: sudo apt-get clean

  2. Move /home mount point to different drive. Previously, my home folder was situated on root drive. So I moved my home folder to separate drive. This helped me to release lot of stress from root mount because most of applications store their data in /home/user_name/ folder. Read how to move home folder to separate drive.

  3. Increase size of root partition I know it is very obvious answer. But believe me, our data need changes over the time. I thought 20 GB /root mount would suffice but withing a year I have re-sized my root mount and increased to 50 GB.

share|improve this answer
sudo apt-get clean freed up more space than expected, +1 – btk Mar 1 '14 at 2:46
Beware that apt-get clean removes even installed packages. You may want to keep those in case an upgrade fails. – timss Jul 12 '15 at 13:56
I cleaned my cache and it cleared up 10 Gb! +1 – Numeri Feb 9 at 16:55

I successfully cleared 3.5 GB by removing old headers and images, using the following command:

dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d' | xargs sudo apt-get -y purge

WARNING: Back up your system, I don't fully understand what this command does, but it messes with kernel headers and the bootloader! You can check what packages will be purged executing the first part of the command:

dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d'


share|improve this answer
Other tips didn't help, but this saved me around 5G. Thanks. – baltasvejas Apr 14 '15 at 8:07
sudo apt-get autoclean  // clean /var/cache/apt/archives folder witch save packages while install.
sudo apt-get autoremove //this command remove unused lib packages.

sudo shutdown -rf // it will restart your pc immediately and check filesystem in next boot.
share|improve this answer
You provide no explanations. If someone was to just copy/paste your code, then the system would shut down with no warning, possibly causing a loss of data. Please don't provide commands without any explanation of what they do. -1 – Jo-Erlend Schinstad Aug 20 '11 at 19:14
Why the need to check the filesystem? – Nathan Osman Aug 20 '11 at 21:46

Use dpkg-query to find the largest packages and remove the ones you don't need anymore.

dpkg-query --show --showformat='${Package;-50}\t${Installed-Size}\n' | sort -k 2 -n | grep -v deinstall | awk '{printf "%.3f MB \t %s\n", $2/(1024), $1}'


share|improve this answer
Now this is a really useful one-liner. Perfect for a quick summary of the biggest install packages. Come to my dotfiles! – arainone Jul 1 at 18:27

In Ubuntu, each folder can have its own filesystem. That means you can move any folder onto its own partition, another disk or even on a remote network. This is particularly popular for home directories, since that means you can reinstall Ubuntu without changing your personal settings or loosing any files. It's also popular in networks where users should be able to log onto different machines and still get their personal settings and files. But it is useful in many different cases, such as yours.

Applications aren't installed into a specific folder, like you seem to suggest. Different parts of the application is placed in different parts of the filesystem. The main program is usually placed in /usr/bin, whereas configuration files are placed in /etc, for instance. In your case, MySQL, the databases themselves are placed somewhere in /var. I think /var/mysql.

Since /usr and /var are both directories in the root filesystem, they will use the root filesystems space. But as I said, you can move them to different filesystems. In the case of MySQL, you can configure where databases are stored. You could easily move databases to /home/username/.mysql/databases for instance.

share|improve this answer

You cannot change the path where the package manager install applications. Most application files are saved to /usr. If you want to recover space on the root partition, moving /usr to a different partition is a possible solution.

From comments:

  • Preserve the permissions when copying, i.e. better use the command line if you are unsure what your file manager will do.

  • The right way to this, is to mount a new filesystem to /usr or use mount --bind. It's not clear how well a symlink would work.

share|improve this answer
careful about move /usr. use cp command to copy usr folder with same permission. then delete original /usr folder and create a link of usr folder on / . – shantanu Aug 20 '11 at 19:04
It should have a mount point. Not a link. – Jo-Erlend Schinstad Aug 20 '11 at 19:12
Small note: a lot of applications also install binaries and application data into /opt. – Nathan Osman Aug 20 '11 at 21:45
@george-edison Well, some applications install stuff in /opt against "the rules". – Jan Aug 20 '11 at 21:57

Following the instructions on the Ubuntu community docs I discovered a massive trash file -- it looked like a backup of /var/log/syslog.1, presumably something was spewing loads of output to syslog...

The command that found it was:

sudo find / -size +1G

And then any large file in a folder called .Trash is probably good to delete...

share|improve this answer

When I need make more free space on servers I use this command. It find all files bigger then 50 MB and "du -h" make berret list of files and "sort -n" after pipe make list numericcaly sorted by file size.

find / -type f -size +50M -exec du -h {} \; | sort -n
share|improve this answer

Removing old kernel versions (as suggested already by homebrand) can free up a decent amount of space if you haven't yet got around to doing that.

There's a number of ways to remove the old kernel versions and a range of different options can be found in the answers posted to the question linked below:

How do I remove old kernel versions to clean up the boot menu?

My preferred method is mostly this answer from penreturns where it's broken down into fairly simple understandable steps:

Open terminal and check your current kernel:

uname -r


Next, type the command below to view/list all installed kernels on your system.

dpkg --list | grep linux-image

Find all the kernels that are lower than your current kernel. When you know which kernel to remove, continue below to remove it.

Run the command below to remove the kernel you selected.

sudo apt-get purge linux-image-x.x.x.x-generic

The answer then says to 'update-grub2' when you're finished purging, which is likely to be out of date now: sudo update-grub should suffice for Ubuntu 14.04 onwards. They also then say to 'Reboot your system' (which seems to be so that you can see the cleaned up boot menu) so in this case isn't necessary.

The grub bootloader menu used to show all the older kernel versions on the main page but they are now placed out of the way behind a sub-menu. It's much neater but a newcomer to Ubuntu/Linux may not be aware that they are there taking up space.

As suggested, don't remove the current kernel and it's also advisable to keep the previous kernel version too, just in case you need to roll back to that one.

There are faster ways to do this, but I prefer the simplicity of this method mainly because I can understand each command along the way:

"What kernel version am I using? What kernel versions do I have? Okay, purge that one."

Rinse, repeat, admire the space you've freed up.

It's fairly easy to copy the name of the specific older kernel you want to remove from the results that dpkg --list | grep linux-image gives you in the terminal, and then use sudo apt-get purge and paste the copied name in.

Removing 3 or 4 older kernels will usually free up about a GB of space in your root drive.

share|improve this answer

If you have a lot of seperate filesystems, the following trick might prove handy: Mount / another time, but this time under /mnt. Now all of your searching for large or many files can be done, without traversing wrong fileystems.

It can also help you find the files that are hidden under another mount.

share|improve this answer
Down voter care to explain? – steviethecat May 18 at 9:59

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.