Ubuntu images big?

LXD
1

Can someone explain why the ubuntu official images are twice as big as the “normal” ubuntu images?

lxc image list ubuntu:18.04/amd64
    +------------+--------------+--------+---------------------------------------------+--------------+-----------------+----------+-------------------------------+
    |   ALIAS    | FINGERPRINT  | PUBLIC |                 DESCRIPTION                 | ARCHITECTURE |      TYPE       |   SIZE   |          UPLOAD DATE          |
    +------------+--------------+--------+---------------------------------------------+--------------+-----------------+----------+-------------------------------+
    | b (5 more) | 3d8ba1d6c3fb | yes    | ubuntu 18.04 LTS amd64 (release) (20210129) | x86_64       | CONTAINER       | 190.35MB | Jan 29, 2021 at 12:00am (UTC) |
    +------------+--------------+--------+---------------------------------------------+--------------+-----------------+----------+-------------------------------+
    | b (5 more) | dc0a7d127e63 | yes    | ubuntu 18.04 LTS amd64 (release) (20210129) | x86_64       | VIRTUAL-MACHINE | 344.88MB | Jan 29, 2021 at 12:00am (UTC) |
    +------------+--------------+--------+---------------------------------------------+--------------+-----------------+----------+-------------------------------+

lxc image list images:ubuntu/18.04/amd64
    +-----------------------+--------------+--------+--------------------------------------+--------------+-----------------+----------+------------------------------+
    |         ALIAS         | FINGERPRINT  | PUBLIC |             DESCRIPTION              | ARCHITECTURE |      TYPE       |   SIZE   |         UPLOAD DATE          |
    +-----------------------+--------------+--------+--------------------------------------+--------------+-----------------+----------+------------------------------+
    | ubuntu/18.04 (7 more) | 6cd5f934b24f | yes    | Ubuntu bionic amd64 (20210203_07:42) | x86_64       | CONTAINER       | 98.02MB  | Feb 3, 2021 at 12:00am (UTC) |
    +-----------------------+--------------+--------+--------------------------------------+--------------+-----------------+----------+------------------------------+
    | ubuntu/18.04 (7 more) | 2490a2e91809 | yes    | Ubuntu bionic amd64 (20210203_07:42) | x86_64       | VIRTUAL-MACHINE | 224.94MB | Feb 3, 2021 at 12:00am (UTC) |
    +-----------------------+--------------+--------+--------------------------------------+--------------+-----------------+----------+------------------------------+
2

The official Ubuntu images include cloud-init, snapd and a variety of other convenience tools which we do not include in the community images.

3

Thanks. I’d suggest that it would be better if cloud-init were in the community images also (then anything else can be simply added on start-up) rather always having to go with a bloated image and stripping out, or more complex init scripts for the smaller image. That would work for simplicity and also give convenience and stability for more complex use-cases.

But, obviously, people have made these decisions for other reasons.

4

That’s what the cloud variant of the community images are for.

images:ubuntu/18.04/cloud/amd64

5

My apologies. User error.

I was listing images using:

$ lxc image list -images:ubuntu/18.04/amd64/cloud

which found nothing,

what I should have done was:

$ lxc image list -images:ubuntu 18.04 amd64 cloud

which got the result I wanted.

RTFM!

6

This shows all available images from the images: repository, either container images or virtual machine images. Note there is no - in images:.

$ lxc image list -images:ubuntu/18.04/amd64/cloud
Error: unknown shorthand flag: 'i' in -images:ubuntu/18.04/amd64/cloud
$ lxc image list images:
...

At the very end you can add filters. The following are equivalent; there can be spaces or not after the repository name.

$ lxc image list images:cloud | wc -l
327
$ lxc image list images: cloud | wc -l
327
$

If you add / to the filter, then you can narrow down the results. In your example, you have a typo.

$ lxc image list images:ubuntu/18.04/amd64/cloud
... none found ...
$ lxc image list images:ubuntu/18.04/cloud/amd64
...shows results...
7

thanks @simos I spotted the typos after I’d posted.

Unfortunately different distros use a different sequence for their tags in the aliases. I guess it shows how they manage the images.