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Remove all unused kernels with apt-get

Terminal - Remove all unused kernels with apt-get
sudo apt-get remove $(dpkg -l|awk '/^ii linux-image-/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic*//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic*\nlinux-image-%s-generic*\n",$0,$0,$0)}')
2012-08-15 10:02:12
User: mtron
Functions: awk sed sudo
3
Remove all unused kernels with apt-get

Remove old kernels (*-generic and *-generic-pae) via apt-get on debian/ubuntu based systems. Tested on ubuntu 10.04 - 12.04.

Alternatives

There are 5 alternatives - vote for the best!

Terminal - Alternatives
aptitude remove $(dpkg -l|egrep '^ii linux-(im|he)'|awk '{print $2}'|grep -v `uname -r`)
2010-06-10 21:23:00
User: dbbolton
Functions: awk egrep grep
8

This should do the same thing and is about 70 chars shorter.

aptitude remove $(dpkg -l|awk '/^ii linux-image-2/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic\nlinux-image-%s-generic\n",$0,$0,$0)}')
2010-12-11 11:38:15
User: __
Functions: awk sed
7

Note the double space: "...^ii␣␣linux-image-2..."

Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel).

I'm bummed that this took 228 characters. I'd like to see a simpler version.

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
2010-06-10 20:33:32
User: mitzip
Functions: sed sudo xargs
4

This will remove all installed kernels on your debian based install, except the one you're currently using.

From:

http://tuxtweaks.com/2009/12/remove-old-kernels-in-ubuntu/comment-page-1/#comment-1590

aptitude remove ?and(~i~nlinux-(im|he) ?not(~n`uname -r`))
2010-06-11 22:57:09
User: dbbolton
2

A little aptitude magic. Note: this will remove images AND headers. If you just want to remove images: aptitude remove ?and(~i~nlinux-im ?not(~n`uname -r`))

I used this in zsh without any problems. I'm not sure how other shells will interpret some of the special characters used in the aptitude search terms. Use -s to simulate.

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

Know a better way?

If you can do better, submit your command here.

What others think

I'd add the --purge option after remove so there's nothing left behind.

Comment by unixmonkey10245 224 weeks and 3 days ago

Your point of view

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