I have ubuntu:18.04 LXC Images downloaded in my local machine, I just want to convert that
ubuntu 18.04 LXC Image into ubuntu18 and ubuntu18.root file. How can i do that?
A container image is made of a pair of
- the metadata file
- the rootfs (as a squashfs image)
You can export any container image to those pairs of files.
Let’s see with a locally cached container image.
$ lxc image list
+-------+--------------+--------+---------------------------------------------+--------+----------+------------------------------+
| ALIAS | FINGERPRINT | PUBLIC | DESCRIPTION | ARCH | SIZE | UPLOAD DATE |
+-------+--------------+--------+---------------------------------------------+--------+----------+------------------------------+
| u18 | 0b969c724698 | no | ubuntu 18.04 LTS amd64 (release) (20190307) | x86_64 | 177.72MB | Mar 8, 2019 at 10:21am (UTC) |
+-------+--------------+--------+---------------------------------------------+--------+----------+------------------------------+
We export it with lxc image export.
$ lxc image export 0b969c724698
Image exported successfully!
$ ls -l
total 181984
-rw-r--r-- 1 myusername myusername 186347520 Mar 21 11:46 0b969c724698d2337eba00540128e26b17ff608a761c28fe7f91b9aef14c3a6e.squashfs
-rw-r--r-- 1 myusername myusername 788 Mar 21 11:46 meta-0b969c724698d2337eba00540128e26b17ff608a761c28fe7f91b9aef14c3a6e.tar.xz
$ tar tvfa meta-0b969c724698d2337eba00540128e26b17ff608a761c28fe7f91b9aef14c3a6e.tar.xz
-rw-r--r-- root/root 1048 2019-03-07 18:39 metadata.yaml
drwxr-xr-x root/root 0 2019-03-07 18:39 templates/
-rw-r--r-- root/root 110 2019-03-07 18:39 templates/cloud-init-meta.tpl
-rw-r--r-- root/root 324 2019-03-07 18:39 templates/cloud-init-network.tpl
-rw-r--r-- root/root 55 2019-03-07 18:39 templates/cloud-init-user.tpl
-rw-r--r-- root/root 21 2019-03-07 18:39 templates/hostname.tpl
-rw-r--r-- root/root 57 2019-03-07 18:39 templates/cloud-init-vendor.tpl
We can do the same with any container image from any container image repository.
For example,
$ lxc image list ubuntu:
...
$ lxc image export ubuntu:18.04
Exporting the image: rootfs: 50% (9.48MB/s)
Image exported successfully!
$ ls
ubuntu-18.04-server-cloudimg-amd64-lxd.tar.xz
ubuntu-18.04-server-cloudimg-amd64.squashfs
$
1 Like
yes, I was able to generate ubuntu18 and ubuntu18.root files from ubuntu:18.04 LXC Image
sudo lxc image export ubuntu18
It will generate ubuntu18 and ubuntu18.04 in the current Directory
Indeed.
Note that the commands that start with lxc (as in lxc image export ...) are part of LXD. If the commands are like lxc-create, lxc-start, lxc-attach, then these are LXC commands. See the difference between LXC and LXD.