There is a very minimal Ubuntu release I have found. This is as bare-bones as it can be. This could be the basis of a custom Linux distribution.
Download a copy here: http://cdimage.ubuntu.com/ubuntu-base/releases/19.10/release/ubuntu-base-19.10-base-amd64.tar.gz.
I had a spare 35 Gigabyte Linux partition, so I unpacked the contents of the tarball into the partition so that it looks as shown below.
root@Yog-Sothoth:/# ls -hula total 56K drwxr-xr-x 17 root root 4.0K Mar 11 21:50 . drwxr-xr-x 17 root root 4.0K Mar 11 21:50 .. lrwxrwxrwx 1 root root 7 Mar 11 21:50 bin -> usr/bin drwxr-xr-x 2 root root 4.0K Mar 11 21:50 boot drwxr-xr-x 22 root root 5.1K Mar 12 2020 dev drwxr-xr-x 31 root root 4.0K Mar 11 21:56 etc drwxr-xr-x 2 root root 4.0K Mar 11 21:50 home lrwxrwxrwx 1 root root 7 Mar 11 21:50 lib -> usr/lib lrwxrwxrwx 1 root root 9 Mar 11 21:50 lib32 -> usr/lib32 lrwxrwxrwx 1 root root 9 Mar 11 21:50 lib64 -> usr/lib64 lrwxrwxrwx 1 root root 10 Mar 11 21:50 libx32 -> usr/libx32 drwxr-xr-x 2 root root 4.0K Mar 11 21:50 media drwxr-xr-x 2 root root 4.0K Mar 11 21:50 mnt drwxr-xr-x 2 root root 4.0K Mar 11 21:50 opt dr-xr-xr-x 304 root root 0 Mar 12 2020 proc drwx------ 2 root root 4.0K Mar 11 21:50 root drwxr-xr-x 4 root root 4.0K Mar 11 21:50 run lrwxrwxrwx 1 root root 8 Mar 11 21:50 sbin -> usr/sbin drwxr-xr-x 2 root root 4.0K Mar 11 21:50 srv dr-xr-xr-x 13 root root 0 Mar 12 2020 sys drwxrwxrwt 2 root root 4.0K Mar 11 21:50 tmp drwxr-xr-x 13 root root 4.0K Mar 11 21:50 usr drwxr-xr-x 11 root root 4.0K Mar 11 21:50 var |
Then I needed to access the command line of the installed distribution. So, I needed to chroot into it.
Firstly, I needed to unmount the partition, and then mount it to a folder under /mnt. Where /dev/sdb3 is the device we are installing to.
root@Yog-Sothoth:~# mount /dev/sdb3 /mnt/fedora-root/ |
This paves the way for the rest of this process.
Then I needed to mount the /proc folder properly.
root@Yog-Sothoth:~# mount -t proc proc /mnt/fedora-root/proc/ |
And the /sys folder.
root@Yog-Sothoth:~# mount -t sysfs sys /mnt/fedora-root/sys |
Finally, the /dev folder needs to be mounted properly.
root@Yog-Sothoth:~# mount -o bind /dev /mnt/fedora-root/dev/ |
If everything worked, you can chroot into the folder to actually use the Linux system.
root@Yog-Sothoth:~# chroot /mnt/fedora-root/ /bin/bash |
Now I can install packages in the chroot just as in my main OS.
root@Yog-Sothoth:~# apt install mc vim nano nmap Reading package lists... Done Building dependency tree Reading state information... Done The following additional packages will be installed: file libblas3 libexpat1 libglib2.0-0 libglib2.0-data libgpm2 libicu63 liblinear3 liblua5.3-0 libmagic-mgc libmagic1 libmpdec2 libpcap0.8 libpython3.7 libpython3.7-minimal libpython3.7-stdlib libreadline8 libslang2 libsqlite3-0 libssh2-1 libssl1.1 libxml2 lua-lpeg mc-data mime-support nmap-common readline-common shared-mime-info unzip vim-common vim-runtime xdg-user-dirs xxd xz-utils Suggested packages: gpm liblinear-tools liblinear-dev arj catdvi | texlive-binaries dbview djvulibre-bin epub-utils genisoimage gv imagemagick libaspell-dev links | w3m | lynx odt2txt poppler-utils python python-boto python-tz xpdf | pdf-viewer zip spell ncat ndiff zenmap readline-doc ctags vim-doc vim-scripts The following NEW packages will be installed: file libblas3 libexpat1 libglib2.0-0 libglib2.0-data libgpm2 libicu63 liblinear3 liblua5.3-0 libmagic-mgc libmagic1 libmpdec2 libpcap0.8 libpython3.7 libpython3.7-minimal libpython3.7-stdlib libreadline8 libslang2 libsqlite3-0 libssh2-1 libssl1.1 libxml2 lua-lpeg mc mc-data mime-support nano nmap nmap-common readline-common shared-mime-info unzip vim vim-common vim-runtime xdg-user-dirs xxd xz-utils 0 upgraded, 38 newly installed, 0 to remove and 0 not upgraded. Need to get 32.5 MB of archives. After this operation, 144 MB of additional disk space will be used. Do you want to continue? [Y/n] |
This is very useful, it is a minimal system, but after running apt update && apt upgrade, it works just fine.
root@Yog-Sothoth:~# df -Hla Filesystem Size Used Avail Use% Mounted on /dev/sdb3 34G 495M 32G 2% / proc 0 0 0 - /proc sys 0 0 0 - /sys udev 6.2G 0 6.2G 0% /dev |
I guess this could be very useful for testing various things. A very nice testing environment. I guess it could be possible to remove Systemd and install another init system, but it might be tied into the operating system packages too much, like many Ubuntu packages used to be. You used to try and remove OpenOffice and it would take half the system with it.
But this is a very interesting project and well worth trying out.
I updated GRUB on my host system and it found the installation on /dev/sdb3, so it might even be bootable.
4.4 Thu Mar 12 jason@Yog-Sothoth 0: $ sudo update-grub 1) All commands run with root privileges are always dangerous. 2) Never run commands on an environment you are not willing to destroy, or able to restore. 3) Do not become root until you know what you are going to do. 4) Be sure of your command and what is going to be affected by it. [sudo] password for jason: Sourcing file `/etc/default/grub' Generating grub configuration file ... Found linux image: /boot/vmlinuz-4.15.0-91-generic Found initrd image: /boot/initrd.img-4.15.0-91-generic Found linux image: /boot/vmlinuz-4.15.0-89-generic Found initrd image: /boot/initrd.img-4.15.0-89-generic Found linux image: /boot/vmlinuz-4.15.0-87-generic Found initrd image: /boot/initrd.img-4.15.0-87-generic Found linux image: /boot/vmlinuz-4.15.0-76-generic Found initrd image: /boot/initrd.img-4.15.0-76-generic Found linux image: /boot/vmlinuz-4.15.0-75-generic Found initrd image: /boot/initrd.img-4.15.0-75-generic Found linux image: /boot/vmlinuz-4.15.0-74-generic Found initrd image: /boot/initrd.img-4.15.0-74-generic Found memtest86+ image: /boot/memtest86+.elf Found memtest86+ image: /boot/memtest86+.bin Found Windows 8 on /dev/sdb1 Found Ubuntu 19.10 (19.10) on /dev/sdb3 done |
Install this package to get the Linux kernel and associated packages installed.
root@Yog-Sothoth:/# apt install linux-generic |
Then, I chose to install GRUB on /dev/sda3 and it added my other partitions to it.