How to cleanup the /boot partition on Ubuntu Linux
by Riley MacDonald, June 27, 2017
My headless Ubuntu Server ran into issues when attempting to install (kernel) updates:
# When trying to upgrade $ sudo apt-get upgrade # The following was observed Setting up linux-image-extra-4.4.0-81-generic (4.4.0-81.104) ... run-parts: executing /etc/kernel/postinst.d/apt-auto-removal 4.4.0-81-generic /boot/vmlinuz-4.4.0-81-generic run-parts: executing /etc/kernel/postinst.d/initramfs-tools 4.4.0-81-generic /boot/vmlinuz-4.4.0-81-generic update-initramfs: Generating /boot/initrd.img-4.4.0-81-generic W: mdadm: /etc/mdadm/mdadm.conf defines no arrays. gzip: stdout: No space left on device E: mkinitramfs failure cpio 141 gzip 1 update-initramfs: failed for /boot/initrd.img-4.4.0-81-generic with 1. run-parts: /etc/kernel/postinst.d/initramfs-tools exited with return code 1 dpkg: error processing package linux-image-extra-4.4.0-81-generic (--configure): subprocess installed post-installation script returned error exit status 1 dpkg: dependency problems prevent configuration of linux-image-generic: linux-image-generic depends on linux-image-extra-4.4.0-81-generic; however: Package linux-image-extra-4.4.0-81-generic is not configured yet. dpkg: error processing package linux-image-generic (--configure): dependency problems - leaving unconfigured dpkg: dependency problems prevent configuration of linux-generic: linux-generic depends on linux-image-generic (= 4.4.0.81.87); however: Package linux-image-generic is not configured yet. dpkg: error processing package linux-generic (--configure): dependency problems - leaving unconfigured No apport report written because the error message indicates its a followup error from a previous failure. No apport report written because the error message indicates its a followup error from a previous failure. Errors were encountered while processing: linux-image-extra-4.4.0-81-generic linux-image-generic linux-generic E: Sub-process /usr/bin/dpkg returned an error code (1) |
gzip: stdout: No space left on device Uh oh, something’s full!
Let’s take a look at the disk space using the disk space usage tool df.
# -a, --all; include dummy file systems $ df -a Filesystem 1K-blocks Used Available Use% Mounted on sysfs 0 0 0 - /sys proc 0 0 0 - /proc udev 938928 0 938928 0% /dev devpts 0 0 0 - /dev/pts tmpfs 191816 20348 171468 11% /run /dev/mapper/bridget--vg-root 305103120 266315512 23266228 92% / securityfs 0 0 0 - /sys/kernel/security tmpfs 959072 0 959072 0% /dev/shm tmpfs 5120 0 5120 0% /run/lock tmpfs 959072 0 959072 0% /sys/fs/cgroup cgroup 0 0 0 - /sys/fs/cgroup/systemd pstore 0 0 0 - /sys/fs/pstore cgroup 0 0 0 - /sys/fs/cgroup/blkio cgroup 0 0 0 - /sys/fs/cgroup/hugetlb cgroup 0 0 0 - /sys/fs/cgroup/cpu,cpuacct cgroup 0 0 0 - /sys/fs/cgroup/memory cgroup 0 0 0 - /sys/fs/cgroup/devices cgroup 0 0 0 - /sys/fs/cgroup/freezer cgroup 0 0 0 - /sys/fs/cgroup/net_cls,net_prio cgroup 0 0 0 - /sys/fs/cgroup/perf_event cgroup 0 0 0 - /sys/fs/cgroup/cpuset cgroup 0 0 0 - /sys/fs/cgroup/pids systemd-1 0 0 0 - /proc/sys/fs/binfmt_misc debugfs 0 0 0 - /sys/kernel/debug hugetlbfs 0 0 0 - /dev/hugepages mqueue 0 0 0 - /dev/mqueue fusectl 0 0 0 - /sys/fs/fuse/connections /dev/sdb 76766184 70168 72773384 1% /mnt/backup_drive /dev/sda1 482922 452559 5429 99% /boot cgmfs 100 0 100 0% /run/cgmanager/fs lxcfs 0 0 0 - /var/lib/lxcfs /home/user/.Private 305103120 266315512 23266228 92% /home/user tmpfs 191816 0 191816 0% /run/user/119 |
/boot is 99% full! My machine doesn’t have a very large drive (yet). It’s just performing some minuscule tasks for me. Let’s check to see how many kernels are on disk since I installed the system a few months ago.
# List the kernels but only show the installed ones $ sudo dpkg --list 'linux-image*' | grep ^ii ii linux-image-4.4.0-64-generic 4.4.0-64.85 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP ii linux-image-4.4.0-66-generic 4.4.0-66.87 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP ii linux-image-4.4.0-70-generic 4.4.0-70.91 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP ii linux-image-4.4.0-71-generic 4.4.0-71.92 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP ii linux-image-4.4.0-72-generic 4.4.0-72.93 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP ii linux-image-4.4.0-75-generic 4.4.0-75.96 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP ii linux-image-4.4.0-78-generic 4.4.0-78.99 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP ii linux-image-4.4.0-79-generic 4.4.0-79.100 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP ii linux-image-4.4.0-81-generic 4.4.0-81.104 amd64 Linux kernel image for version 4.4.0 on 64 bit x86 SMP ii linux-image-extra-4.4.0-64-generic 4.4.0-64.85 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP ii linux-image-extra-4.4.0-66-generic 4.4.0-66.87 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP ii linux-image-extra-4.4.0-70-generic 4.4.0-70.91 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP ii linux-image-extra-4.4.0-71-generic 4.4.0-71.92 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP ii linux-image-extra-4.4.0-72-generic 4.4.0-72.93 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP ii linux-image-extra-4.4.0-75-generic 4.4.0-75.96 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP ii linux-image-extra-4.4.0-78-generic 4.4.0-78.99 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP ii linux-image-extra-4.4.0-79-generic 4.4.0-79.100 amd64 Linux kernel extra modules for version 4.4.0 on 64 bit x86 SMP |
Let’s double check the current kernel.
$ uname -a Linux server_name 4.4.0-79-generic #100-Ubuntu SMP Wed May 17 19:58:14 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux |
No need to keep all of these kernels around, the system has been stable for quite some time now. Some users and Ubuntu itself output will suggest running autoremove to cleanup unused kernels but I don’t feel safe running that command. I like to keep at least 3 of the most recent kernels in case I need to revert back to a previous version.
I’ll just remove a few to free up some disk space for now:
$ sudo apt-get remove linux-image-4.4.0-64-generic linux-image-extra-4.4.0-64-generic linux-image-4.4.0-66-generic linux-image-extra-4.4.0-66-generic # ... After this operation, 438 MB disk space will be freed. Do you want to continue? [Y/n] Y # My previously failed upgrade kicked right in and finished after the remove operation. Setting up linux-image-generic (4.4.0.81.87) ... Setting up linux-generic (4.4.0.81.87) ... # Check the boot partition now $ df /boot/ Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda1 482922 354074 103914 78% /boot |
Great, this should hold me over until a larger disk is installed.