658

My /boot partition is nearly full and I get a warning every time I reboot my system. I already deleted old kernel packages (linux-headers...), actually I did that to install a newer kernel version that came with the automatic updates.

After installing that new version, the partition is nearly full again. So what else can I delete? Are there some other files associated to the old kernel images?

Here is a list of files that are on my /boot partition:

:~$ ls /boot/
abi-2.6.31-21-generic         lost+found
abi-2.6.32-25-generic         memtest86+.bin
abi-2.6.38-10-generic         memtest86+_multiboot.bin
abi-2.6.38-11-generic         System.map-2.6.31-21-generic
abi-2.6.38-12-generic         System.map-2.6.32-25-generic
abi-2.6.38-8-generic          System.map-2.6.38-10-generic
abi-3.0.0-12-generic          System.map-2.6.38-11-generic
abi-3.0.0-13-generic          System.map-2.6.38-12-generic
abi-3.0.0-14-generic          System.map-2.6.38-8-generic
boot                          System.map-3.0.0-12-generic
config-2.6.31-21-generic      System.map-3.0.0-13-generic
config-2.6.32-25-generic      System.map-3.0.0-14-generic
config-2.6.38-10-generic      vmcoreinfo-2.6.31-21-generic
config-2.6.38-11-generic      vmcoreinfo-2.6.32-25-generic
config-2.6.38-12-generic      vmcoreinfo-2.6.38-10-generic
config-2.6.38-8-generic       vmcoreinfo-2.6.38-11-generic
config-3.0.0-12-generic       vmcoreinfo-2.6.38-12-generic
config-3.0.0-13-generic       vmcoreinfo-2.6.38-8-generic
config-3.0.0-14-generic       vmcoreinfo-3.0.0-12-generic
extlinux                      vmcoreinfo-3.0.0-13-generic
grub                          vmcoreinfo-3.0.0-14-generic
initrd.img-2.6.31-21-generic  vmlinuz-2.6.31-21-generic
initrd.img-2.6.32-25-generic  vmlinuz-2.6.32-25-generic
initrd.img-2.6.38-10-generic  vmlinuz-2.6.38-10-generic
initrd.img-2.6.38-11-generic  vmlinuz-2.6.38-11-generic
initrd.img-2.6.38-12-generic  vmlinuz-2.6.38-12-generic
initrd.img-2.6.38-8-generic   vmlinuz-2.6.38-8-generic
initrd.img-3.0.0-12-generic   vmlinuz-3.0.0-12-generic
initrd.img-3.0.0-13-generic   vmlinuz-3.0.0-13-generic
initrd.img-3.0.0-14-generic   vmlinuz-3.0.0-14-generic

Currently, I'm using the 3.0.0-14-generic kernel.

Jastria Rahmat
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user6722
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26 Answers26

726

You've a lot unused kernels. Remove all but the last kernels with:

sudo apt-get purge linux-image-{3.0.0-12,2.6.3{1-21,2-25,8-{1[012],8}}}

This is shorthand for:

sudo apt-get purge linux-image-3.0.0-12 linux-image-2.6.31-21 linux-image-2.6.32-25 linux-image-2.6.38-10 linux-image-2.6.38-11 linux-image-2.6.38-12 linux-image-2.6.38-8

Removing the linux-image-x.x.x-x package will also remove linux-image-x.x.x-x-generic.

The headers are installed into /usr/src and are used when building out-tree kernel modules (like the proprietary nvidia driver and virtualbox). Most users should remove these header packages if the matching kernel package (linux-image-*) is not installed.

To list all installed kernels, run:

dpkg -l linux-image-\* | grep ^ii

One command to show all kernels and headers that can be removed, excluding the current running kernel:

kernelver=$(uname -r | sed -r 's/-[a-z]+//')
dpkg -l linux-{image,headers}-"[0-9]*" | awk '/ii/{print $2}' | grep -ve $kernelver

It selects all packages named starting with linux-headers-<some number> or linux-image-<some number>, prints the package names for installed packages and then excludes the current loaded/running kernel (not necessarily the latest kernel!). This fits in the recommendation of testing a newer kernel before removing older, known-to-work kernels.

So, after upgrading kernels and rebooting to test it, you can remove all other kernels with:

sudo apt-get purge $(dpkg -l linux-{image,headers}-"[0-9]*" | awk '/ii/{print $2}' | grep -ve "$(uname -r | sed -r 's/-[a-z]+//')")
Lekensteyn
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266

Your boot partition is full. Since this is a kernel update, these files will be copied to the boot partition so you need to clean in out. Here is a blog post that will show you how to clear the old kernel images with one command. I'll give a basic synopsis of the method. Use this command to print out the current version of your kernel:

uname -r

Then use this command to print out all the kernels you have installed that aren't your newest kernel:

dpkg -l linux-{image,headers}-"[0-9]*" | awk '/^ii/{ print $2}' | grep -v -e `uname -r | cut -f1,2 -d"-"` | grep -e '[0-9]'

Make sure your current kernel isn't on that list. Notice how this is the majority of the final command (down below). To uninstall and delete these old kernels you will want to pipe these arguments to:

sudo apt-get -y purge

Now we can do everything we want by combining these last two commands into this unholy mess:

dpkg -l linux-{image,headers}-"[0-9]*" | awk '/^ii/{ print $2}' | grep -v -e `uname -r | cut -f1,2 -d"-"` | grep -e '[0-9]' | xargs sudo apt-get -y purge

And that one command will take care of everything for you. I will confirm that this does work perfectly but never trust anybody on the internet. :) For more info, the blog post gives a very good explanation of what each part of the command does so read through it so you are satisfied that it does what you want it to do.

dward
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137
sudo apt-get autoremove

This command is doing the job automatically.

mchid
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karan
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49

The Synaptic Package Manager can be used to easily select and remove old kernel images. Screenshot of Synaptic Package Manager

If you don't already have Synaptic installed:

sudo apt-get install synaptic

Start the application and select the options shown.

You should be able to highlight all the "linux-" packages with the version "2.6.x" where x is between 31 to 38 according to the files in your /boot folder.

Right-click each of those linux packages and choose the option "Mark for Complete Removal". Finally click the apply button. This will remove all the files and any associated files. Your /boot folder should now be a bit tidier.

mwfearnley
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fossfreedom
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26

Thank you for your detailed post of your problem, this got me going in the right direction. Although it is useful to keep previous kernel files you can remove all of them in one go, check this post:
How to Remove All Unused Linux Kernel Headers, Images and Modules

Done via command line. If you are doing this via remote use something like WINSCP to open a terminal session and just paste it in, works very well.

Here it is copied from article link, I suggest you read the full article:

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
Mateo
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Omni
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24

List all kernels:

dpkg --list 'linux-image*'

Display current kernel:

uname -r

List all kernels EXCEPT current one:

dpkg -l linux-{image,headers}-"[0-9]*" | awk '/^ii/{ print $2}' | grep -v -e `uname -r | cut -f1,2 -d"-"` | grep -e '[0-9]'

Make sure your current kernel isn't on that list.

Remove all kernels EXCEPT current one:

dpkg -l linux-{image,headers}-"[0-9]*" | awk '/^ii/{ print $2}' | grep -v -e `uname -r | cut -f1,2 -d"-"` | grep -e '[0-9]' | xargs sudo apt-get -y purge

Clear other stuff:

sudo apt-get autoremove

If it still gives you boot disk space error for installing/uninstalling files then directly remove one of OLD image from /boot directory,

ls -lh /boot/*-3.13.0-119*;

rm /boot/*-3.13.0-119*;

NOTE: Please review current kernel image again before deleting any image.

If it stills throws any error then repeat following commands to remove unwanted kernels,

sudo dpkg --purge linux-image-X.X.X-XXX-generic linux-image-extra-X.X.X-XXX-generic linux-signed-image-X.X.X-XXX-generic
sudo dpkg --purge linux-image-Y.Y.Y-YYY-generic linux-image-extra-Y.Y.Y-YYY-generic linux-signed-image-Y.Y.Y-YYY-generic

sudo apt-get -f install

dpkg -l linux-{image,headers}-"[0-9]*" | awk '/^ii/{ print $2}' | grep -v -e `uname -r | cut -f1,2 -d"-"` | grep -e '[0-9]' | xargs sudo apt-get -y purge
Hemant Thorat
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22

Notice that the software in this answer is not supported since 2016. I do not know of alternatives...

This is a new answer to an old question, but an easy way to clean this thing (and more) is to install Ubuntu Tweak. To install it:

sudo add-apt-repository ppa:tualatrix/ppa
sudo apt-get update
sudo apt-get install ubuntu-tweak

then you can run Ubuntu Tweak, Going to the "janitor" tab, and from here it's a matter of three clicks:

Ubuntu tweak janitor for old kernels

It is better to leave the last kernel (you never know) or a well-known working kernel for safety, though; but that's easily customizable.

You can use the same tool to clean a lot of things --- just remember that if you clean thumbnail cache or TB cache then the system will have to rebuild them if they are needed.

Rmano
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21

I was able to fix the problem by using dpkg to remove the packages directly. Although the packages are still listed in dpkg -l, the files are removed from /boot, freeing up space.

phrogz@planar:/boot$ sudo dpkg --remove linux-image-2.6.32-30-server
(Reading database ... 145199 files and directories currently installed.)
Removing linux-image-2.6.32-30-server ...
Running postrm hook script /usr/sbin/update-grub.
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-2.6.32-35-server
Found linux image: /boot/vmlinuz-2.6.32-34-server
Found initrd image: /boot/initrd.img-2.6.32-34-server
Found linux image: /boot/vmlinuz-2.6.32-33-server
Found initrd image: /boot/initrd.img-2.6.32-33-server
Found linux image: /boot/vmlinuz-2.6.32-32-server
Found initrd image: /boot/initrd.img-2.6.32-32-server
Found linux image: /boot/vmlinuz-2.6.32-31-server
Found initrd image: /boot/initrd.img-2.6.32-31-server
Found memtest86+ image: /memtest86+.bin
done

# Repeat for kernels -31 and -32 and -33, up to (but not including)
# the version listed by `uname -a`

After this, apt-get -f install fixed my dependency problems, and all was well with the world.

I'll not be accepting this answer of mine, however, as I still need to know if I should be increasing my /boot size or doing something else.

Phrogz
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18

You can stop using a separate /boot partition, then you won't have such limited space there. To do this, unmount the partition, then mount it somewhere else and copy all of the files there to the /boot directory in your root partition, then remove the entry from /etc/fstab and reinstall grub. For example ( you will need to use the correct partition ):

sudo -s
umount /boot
mount /dev/sda2 /mnt
cp -a /mnt/* /boot/
umount /mnt
gedit /etc/fstab
grub-install /dev/sda

You can then use gparted to delete the old /boot partition, and possibly extend the root partition to use that space. To extend the root partition you will need to boot from the livecd, and the free space needs to be immediately to the right. If the /boot partition is currently to the left of the root partition, then you will need to first move the root partition to the left, then extend it, but this can take a very, very long time, so may not be worth the trouble.

psusi
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16

Update: current versions (since at least 22.04) periodically purge obsolete kernel versions. However, this does not work under all circumstances – such as when the system has not been rebooted since the last kernel upgrade and is thus still running the older of two upgraded kernels.

Taking the best from the answers above, my tried-and-true approach is this:

  • uname -a to find the running kernel.
  • dpkg -l linux-{headers,image}-\* | grep ^ii to list all currently installed kernel-related packages. This will include the running kernel.
  • sudo apt-get purge linux-{image,headers}-3.16.0-{xx,yy,zz} to remove the old kernels. Replace xx,yy,zz with a list of the kernel builds you want to remove—these are all the builds listed by the previous command which are older than the currently running kernel. Make sure you don't remove the currently running kernel—your system will become unbootable. You may also need to change the kernel version from 3.16.0 to whatever is installed on your system.
  • Optionally, do an additional sudo apt-get autoremove—this will remove any leftover dependencies of the old kernels which are no longer needed by the current one, freeing up some more space.

You may have header files without matching kernel versions installed, or vice versa—just include all of these versions in the command. APT will complain that some packages can't be removed because they are not installed, but that will do no harm.

If something fails...

  • If the apt command fails due to a no space left on device error, use the corresponding dpkg command instead: sudo dpkg --purge linux-{image,headers}-3.16.0-{xx,yy,zz}.
  • If the dpkg command still doesn’t work because the linux-image packages are required by the linux-headers packages of the same version (which you also want to uninstall), dpkg may have failed to resolve that. Re-examine the output of dpkg -l and specify any package name suffixes on the command line. For example, on one of my systems the command that eventually worked was sudo dpkg --purge linux-{image,headers}-3.16.0-{xx,yy,zz}-generic-pae.
  • If you get any other error, seek help—you may have a different problem than you thought.

Automation

This script will perform all the above steps automatically.

As side effects, it will remove all unused dependencies and upgrade all packages on the system (not just the kernel – except for packages that have been held back).

The script can run with user privileges but will invoke sudo for the actual package operations. You will be prompted for any package purge/install operations:

#!/bin/sh
verpattern=[0-9]+\.[0-9]+\.[0-9]+-[0-9]+

Determine currently running kernel by transforming uname -a output


current=$(uname -a | sed -E "s/Linux .* ($verpattern)-[a-z]+ .*/\1/")


if ! ( echo "$current" | egrep -q "$verpattern" ) ; then
    # Something went wrong; abort to prevent damage
    echo "ERROR: cannot determine currently running kernel version"
    exit 1
fi


Determine unused kernel versions: enumerate installed packages, discard entries


for running kernel version (or without version pattern), then isolate the version


from each line, remove duplicates and store version numbers in $oldvers


oldvers=""
for ver in $( dpkg -l linux-headers-* linux-image-* | grep ^ii | grep -Fv "$current" | egrep "$verpattern" | sed -E "s/.* +.* +($verpattern).[0-9]+ .*/\1/" | sort -u ) ; do
    oldvers="$oldvers $ver"
done


pkgs=""
for ver in $oldvers ; do
    for suffix in "image" "image-unsigned" "headers" ; do
        pkgs="$pkgs linux-$suffix-$ver"
    done
done


Purge unused versions ($pkgs), remove obsolete dependencies and upgrade kernel


sudo apt-get purge $pkgs && sudo apt autoremove && sudo apt-get upgrade
user149408
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6

For me both apt-get purge and dpkg --remove both failed. So I had to deleted a couple of older kernel images from /boot with rm -f.

orkoden
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3

I show that still in 2017 this question has new comments and answers but missing one answer that I think is very useful here:

Ubuntu as a desktop OS of simple everyday usage has no reason to be installed with separate /boot partition and something like this will NOT offer something to a "common user"... So a solution is a fresh install without /boot partition and this way you will never have such a problem

phuclv
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koleygr
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2

linux-purge utility is made for the purpose:

Install the utility from Launchpad; you can find instructions from there.

Run:

sudo linux-purge --clear-boot --keep=1 --optimize

--keep=1 means the command will keep 1 kernel older than the current kernel, so 2 in total, if there are at least so many installed. It might keep even more, if you have more than one meta kernels installed. --clear-boot is probably unnecessary; it will purge kernels unknown to the package management system. --optimize is not necessary, but it will speed up the process, if you have many kernels to remove.

You could also use --choose option to choose manually which kernels to remove/purge.

If the above does not work, run

sudo linux-purge --fix

and re-try.

If you find a bug in the software, you can report it in Launchpad. See man linux-purge for more details on that and information about possible command line options.

jarno
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2

I already deleted old kernel packages (linux-headers...)

linux-headers-* aren't kernels. Kernel packages are the ones named linux-image-*. The ones named linux-headers-* are development packages for compiling kernel modules: they don't live in the /boot directory and are not required for general day to day use of your system.

The files you listed in /boot do include several old kernel images (vmlinuz*) and compiled initrd images (initrd.img*) for those kernels, which is an indication that you still have a lot of old kernel packages installed.

You should be able to list your installed kernels with 

aptitude search ~ilinux-image

(Note that this will probably return packages that aren't kernels, too).

There is usually no need for more than two kernels to be installed - the one currently in use and the previous one to that (as a fallback). So you can start removing the older ones, one by one, like this:

sudo apt-get autoremove linux-image-3.2.0-23-generic

Make sure you substitute "3.2.0-23-generic" with the actual kernel version you want to remove! Also, don't remove packages such as linux-image-generic. You have to be really careful not to remove the currently running kernel or you won't be able to boot (Ubuntu may or may not warn you about doing this).

You can find your currently running kernel with:

uname -r
thomasrutter
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1

/boot partition can be bit strange sometimes

do not directly start to delete kernal files.

Steps to follow

  1. Check for the currently installed kernal being used by linux system

    uname -r

    this should give you name of currently installed kernal image on system

  2. Now start deleting extra files except that one specific installed on your system

    apt-get remove linux-image-XXXXX

  3. Also remove the header file as well

    apt-get remove linux-headers-XXXXX

  4. Also there may be a condition where apt has stopped working, in that case switch to /boot

    cd /boot

  5. Start removing files manually but very carefully also keep in the mind not deleting the installed one's kernal files from your system.

    rm linux-image-XXXXX

    rm linux-image-extra-XXXXXX

  6. After removing the correct files cleanup partial installs if any

    apt-get -f install

  7. Remove extra files sitting there as boot files cleaned manually

    apt-get autoremove

  8. Update grub

    update-grub

  9. Lastly update your system packages

    apt-get update

user225
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1

For anyone with full-disk encryption:

Workaround

  1. List installed kernels

    $ dpkg -l | grep linux-image-.*-generic  | grep ^ii
ii  linux-image-5.19.0-50-generic                               5.19.0-50.50                            amd64        Signed kernel image generic
ii  linux-image-6.2.0-39-generic                                6.2.0-39.40~22.04.1                     amd64        Signed kernel image generic
ii  linux-image-6.5.0-14-generic                                6.5.0-14.14~22.04.1                     amd64        Signed kernel image generic
ii  linux-image-6.5.0-15-generic                                6.5.0-15.15~22.04.1                     amd64        Signed kernel image generic

  2. Uninstall the oldest kernel, e.g.

    sudo apt purge linux-image-5.19.0-50-generic linux-modules-5.19.0-50-generic

That should temporarily fix the issue, until of course the next time Ubuntu installs a newer kernel as part of updates

You can also remove one more kernel to give yourself more time until you run into this problem again, but unless /boot is resized it's just a temporary measure.

If you want you can also clean up any unneeded packages afterwards, e.g.

sudo apt autoremove

(Or sudo apt autopurge)

Fix

The real fix would be to resize the /boot partition to make it bigger.

In order to do this, you would first need to shrink the other partitions, but this is made more complicated by the fact that one or more of them are encrypted, to the extent that I'm having trouble finding reliable documentation for how it should be done.

This is the best answer I've found so far as to how to do it: How to edit/resize an LVM partition graphically (with a GUI)?

I finally did this myself and here's how I did it: https://askubuntu.com/a/1533568/18665

Details

None of the other answers have mentioned full-disk encryption. For those of us using full-disk encryption, the /boot partition may be undersized due to this bug: https://bugs.launchpad.net/ubuntu/+source/partman-auto/+bug/1959971

Out of the box, Ubuntu keeps 3 kernels. As far as I understand, this logic is baked into the packages that handle the logic for apt autoremove and there's no way to change it without recompiling those packages. So I suppose that would be a possible "fix," but it doesn't seem to be a viable fix as far as I'm concerned.

In my case, /boot is 704 MB, which should be enough for 3 kernels:

$ df -h /boot
Filesystem      Size  Used Avail Use% Mounted on
/dev/nvme0n1p2  704M  582M   71M  90% /boot

However, when installing updates, Ubuntu will install additional kernels first before removing old kernels, so /boot runs out of space. Here's the log from the last time I ran into this error during an update:

Setting up initramfs-tools (0.140ubuntu13.4) ...
update-initramfs: deferring update (trigger activated)
Setting up linux-firmware (20220329.git681281e4-0ubuntu3.26) ...
update-initramfs: Generating /boot/initrd.img-6.5.0-15-generic
I: The initramfs will attempt to resume from /dev/dm-2
I: (/dev/mapper/vgubuntu-swap_1)
I: Set the RESUME variable to override this.
zstd: error 25 : Write error : No space left on device (cannot write compressed block) 
E: mkinitramfs failure zstd -q -1 -T0 25

And sure enough, 4 kernels are installed:

$ dpkg -l | grep linux-image-.*-generic  | grep ^ii
ii  linux-image-5.19.0-50-generic                               5.19.0-50.50                            amd64        Signed kernel image generic
ii  linux-image-6.2.0-39-generic                                6.2.0-39.40~22.04.1                     amd64        Signed kernel image generic
ii  linux-image-6.5.0-14-generic                                6.5.0-14.14~22.04.1                     amd64        Signed kernel image generic
ii  linux-image-6.5.0-15-generic                                6.5.0-15.15~22.04.1                     amd64        Signed kernel image generic

(There also seems to be other scenarios in which 4 or more kernels may be installed, such as when using HWE packages: Why is Ubuntu keeping 4 kernels installed?)

Even apt autoremove fails because before it will uninstall packages, it first tries to fix existing broken packages, which fails because /boot doesn't have enough space.

bmaupin
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1

Super helpful utility that will clear out your boot partition

git clone https://github.com/erichs/bootnukem.git
cd bootnukem
sudo ./install.sh

Use at your own risk, but it worked for me:

sudo bootnukem
Jonathan
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1

I had this problem and more as I removed some initrd-img-xxx files manually from the /boot and I had a problem that these old versions keep generated and filling in the /boot folder. To fix it I followed the following:

  • I removed the generated old kernel version manually so to free space.

  • You’ll be editing a text configuration file as superuser, so paste the following into a terminal:

    sudo gedit /etc/initramfs-tools/update-initramfs.conf

  • Locate the line update_initramfs=yes and change it to update_initramfs=no. Save and exit the file, then run:

    sudo dpkg --configure -a

That solved my problem. That was based on this blog

Hopefully, everything should be fine when you reboot, and later you can try changing the no back to yes in update-initramfs.conf.

muru
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aibrahim
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1

I wrote this bash script to selective purge old kernels all at once:

rm kernels real size

All the bash code and instructions are included in the link.

WinEunuuchs2Unix
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0

Save this script as /usr/local/bin/remove_kernels.sh (remember to give execute permissions sudo chmod 755 /usr/local/bin/remove_kernels.sh ):

#!/bin/sh
if test $(id -u) != 0; then
 echo Error: You must be root to run this script!
 exit 1
fi
apt purge $( dpkg --list | grep -P -o "linux-image-\d\S+" | grep -v $(uname -r | grep -P -o ".+\d") )
update-grub

Then to remove all old kernels just type: sudo remove_kernels.sh

Anthony Kelly
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0

apt-get purge or apt-get autoremove will only work when the space remaining isn't enough for installing the kernel but still enough for basic apt operations. If the disk is completely full then unfortunately all apt or dpkg calls will fail. In that case you should remove the files from /boot, but rm /boot/$OLD_KERNEL directly like in some other answers is not safe and you should follow the official steps on Ubuntu wiki:

# Remove any leftover temporary files from previous kernel updates
sudo rm -rv ${TMPDIR:-/var/tmp}/mkinitramfs-*

Remove initrd.img for the specified kernel version


sudo update-initramfs -d -k 4.2.0-15-generic


Try purging the kernel package for that version


sudo dpkg --purge linux-image-4.2.0-15-generic # or
sudo dpkg --purge linux-image-4.2.0-15-generic linux-image-extra-4.2.0-15-generic


Fix the package installation


sudo apt-get -f install

Repeat the last 3 steps with other old kernels until everything succeeded

phuclv
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0

Since I have my other partitions encrypted, my only option was to delete unused files in /boot, like unused .mo files in /boot/grub/locale

vejeta
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0

There's a bash script which I wrote give below that makes the process a bit more user-friendly.

YMMV - it was made for Mint 14. Still learning BASH so it's probably a bit clunky. Use at own risk, but it works for me!

#!/bin/bash

endCol='\e[0m'
bold_red='\e[1;31m'
bold_green='\e[1;32m'
bold_yellow='\e[1;33m'

title_color='\e[0;30;47m'

function show_kernel_info {
clear
current_kernel=$(uname -r)
echo "Current ACTIVE kernel is:"
echo -e "  "$bold_yellow$current_kernel$endCol
echo "This kernel will be TOTALLY EXCLUDED from all actions in this script."
echo "Also, one fallback non-active kernel will be always left untouched."
echo ""
echo "These are the non-active kernels stored in /boot:"
count_of_old_kernels_in_boot=$(ls -o /boot/initrd* | grep -c -v "$current_kernel")
if [ $count_of_old_kernels_in_boot = 0 ]; then
  echo " * No non-active kernels found! *"
else
  ls -o /boot/initrd* | grep -v "$current_kernel"
fi
echo ""
list_of_old_kernels=$(dpkg --list | grep linux-image | awk -F' ' '{ print $2 }' | grep -v "$current_kernel" | grep -v "linux-image-generic")
current_old_kernel=$(dpkg --list | grep linux-image | awk -F' ' '{ print $2 }' | grep -v "$current_kernel" | grep -v "linux-image-generic" | head -n 1)
count_of_old_kernels_installed=$(dpkg --list | grep linux-image | awk -F' ' '{ print $2 }' | grep -v "$current_kernel" | grep -c -v "linux-image-generic")
echo "Listing of all unused kernels still installed in the system (these may not exist in /boot):"
if [ $count_of_old_kernels_installed = 0 ]; then
  echo " * No unused kernel installs found! *"
else
  dpkg --list | grep linux-image | awk -F' ' '{ print $2 }' | grep -v "$current_kernel" | grep -v "linux-image-generic"
fi
echo ""
}

function exit_script {
free_space_after=$(df -BM /boot | tail -n 1 | awk -F' ' '{ print $4 }' | tr -d M)
let freed_space=$free_space_after-$free_space_before
echo ""
echo "Results (in MB)"
echo "---------------"
echo "Free space in /boot before script was run: "$free_space_before
echo "Free space now: "$free_space_after
echo ""
echo "Amount of space freed up = "$freed_space
echo ""
echo "Press any key to exit."
read -s -n 1
echo ""
exit
}

# Main code
echo ""
echo -e $title_color" --------------------------- "$endCol
echo -e $title_color" -   Kernel Cleanup v1.0   - "$endCol
echo -e $title_color" --------------------------- "$endCol
echo ""
echo "Maximise this window for readability."
echo "Press any key to continue."
read -s -n 1
echo ""
echo "This script will remove old unused kernels, but it will prompt you before removing each one."
echo "It will never remove the current running kernel, and will also leave one fallback kernel."
echo "It can also remove source files from /usr/src for each kernel removed."
echo "This is normally safe to do and will free up lots more space."
echo ""
echo "Do you want that done as well? (y/n, enter=yes)"
valid_input=0
while [ "$valid_input" = "0" ]; do
  read -s -n 1 YesNo_input
  if [ "$YesNo_input" = "" ]; then
    YesNo_input="y"
  fi
  case $YesNo_input
  in
    y)
    RemoveSource="y"
    valid_input=1
    ;;

    Y)
    RemoveSource="y"
    valid_input=1
    ;;

    n)
    RemoveSource="n"
    valid_input=1
    ;;

    N)
    RemoveSource="N"
    valid_input=1
    ;;
  esac
done

free_space_before=$(df -h /boot | tail -n 1 | awk -F' ' '{ print $4 }' | tr -d M)
show_kernel_info
while [ $count_of_old_kernels_in_boot -gt 1 ]; do
  # failsafe check if somehow the current kernel is about to be removed!
  if [ "$current_old_kernel" = "$current_kernel" ]; then
    echo -e $bold_red"ERROR!"$endCol" Somehow the current kernel has crept into the removal process!"
    echo "I refuse to do that! Aborting script."
    exit_script
  fi
  # failsafe check if somehow a linux-image-generic entry is about to be removed
  if [ "$current_old_kernel" = "linux-image-generic" ]; then
    echo -e $bold_red"ERROR!"$endCol" Somehow one of the linux-image-generic entries has crept into the removal process!"
    echo "I refuse to do that! Aborting script."
    exit_script
  fi
  echo "Command about to be executed is:"
  echo "  $ sudo apt-get purge \"$current_old_kernel\""
  check_in_boot=$(echo $current_old_kernel | sed 's/linux-image/initrd.img/g')
  if [ -e /boot/$check_in_boot ]; then
    echo -e $bold_yellow"Note:"$endCol" This kernel exists in /boot but it NON-active, so it's OK to remove."
  else
    echo -e $bold_green"Totally safe to remove:"$endCol" This kernel does NOT exist in /boot."
  fi
  echo ""
  echo "Are you sure you want to remove this kernel?"
  echo "(*upper case* Y=yes / any other key will exit the script)"
  read -s -n 1 yes_no
  echo ""
  # Only entering a single upper case Y will work!
  if [ "$yes_no" != "Y" ]; then
    echo "Aborting script."
    exit_script
  fi
  echo "Removing kernel "$current_old_kernel"..."
  sleep 1
  sudo apt-get -y purge $current_old_kernel
  if [ "$RemoveSource" = "y" ]; then
    current_old_source=$(echo $current_old_kernel | sed 's/linux-image/linux-headers/g')
    current_old_source=$(echo $current_old_source | sed 's/-generic//g')
    current_old_source=$(echo $current_old_source | sed 's/-pae//g')
    sudo apt-get -y purge $current_old_source
  fi
  show_kernel_info
done

if [ $count_of_old_kernels_in_boot = 0 ]; then
  echo -e $bold_red"There are no NON-active kernels to remove!"$endCol
else
  echo -e $bold_red"There is only one NON-active kernel left in /boot!"$endCol
  echo "This script will not remove the last non-active kernel so that you have at least one backup kernel."
fi
echo "Aborting script."
exit_script
Stormvirux
  • 4,536
wibbynut
  • 1
0

[As an AskUbuntu noob I can't comment until reputation = 50 so don't down-vote because of this.]

My server was doing this, too. Literally none of the expected answers here worked since these require some working room on /boot for them to complete. If the boot partition is full, it will abruptly end without deleting any of the images.

The only thing that worked for me was to review the current image, then to manually sudo rm filename for the oldest image files (each had -3.16.0-30 in their names). Once that was done, then sudo apt-get autoremove had the wiggle-room it needed to do its job. It did highlight some errors associated with that version, for example: "depmod: FATAL: could not load /boot/System.map-3.16.0-30-generic: No such file or directory" but that is to be expected.

When finished, the df returned a 42% in use for /boot to indicate that it's healthy again.

Justin Case
  • 61
  • 5
0

In aptitude or synaptic there is a section "old or manually installed packaged". There should be the old linux packages there.

Martin Ueding
  • 8,436
-1

If you cannot remove more unused files and if you have other partition with/or free space on same device, you can resize of /boot partition by parted/gparted. (It is included on installation media, too.)

Warning: Resizing of partition is dangerous operation, save your important data on other media before doing it!

Rudolf Dovičín
  • 317