Documentation for general installation in containerized environments

[me-coder]

The CFEngine installation guide is missing out on containers.
This PR is an attempt to project the capability of CFEngine with containers (using ubi9-init images).

There are a few limitations due to the nature of CFEngine (requires privileged mode and container is required to have systemd, which need initialization with /var/sbin/init).
However, it still gives a good ability to test CFEngine in containerized environments in full capacity, without the need to have a bulky multi VM setup.

Hope the moderator team finds this useful and decides to integrate it into the docs.

[me-coder]

I am unable to figure out the reason for failure of check with:
Run markdowner.py on all markdown files and see if there are changes / check (pull_request)

Any help to deal with this cryptic error is appreciated.

[olehermanse]

I am unable to figure out the reason for failure of check with:
Run markdowner.py on all markdown files and see if there are changes / check (pull_request)

Any help to deal with this cryptic error is appreciated.

Your files have extra spaces in them, at the ends of multiple lines.
Change your editor to automatically trim trailing whitespace for you, or run the command as suggested;

python3 .github/workflows/markdowner.py ./getting-started/installation/general-installation/installation-community-containerized.markdown

That will edit the file, removing those extra unnecessary spaces.
(Afterwards you will need to add and commit those changes - git add -p ; git commit).

[me-coder]

I am unable to figure out the reason for failure of check with:
Run markdowner.py on all markdown files and see if there are changes / check (pull_request)

Any help to deal with this cryptic error is appreciated.

Your files have extra spaces in them, at the ends of multiple lines. Change your editor to automatically trim trailing whitespace for you, or run the command as suggested;

python3 .github/workflows/markdowner.py ./getting-started/installation/general-installation/installation-community-containerized.markdown

That will edit the file, removing those extra unnecessary spaces. (Afterwards you will need to add and commit those changes - git add -p ; git commit).

The extra spaces (particularly ^.+<space><space>$ was required for newline as per the markdown requirements.
However, that has been replaced by </br> now and seems to have worked.
Thanks for the suggestion.

[me-coder]

@olehermanse,
I've made this change to take care of such situations, if encountered by other contributors:
c9719c9

Hope that's fine.

[olehermanse]

The extra spaces (particularly ^.+$ was required for newline as per the markdown requirements.

What requirements? This is not required.

However, that has been replaced by
now and seems to have worked.

No, remove these, they are not necessary.

I've made this change to take care of such situations, if encountered by other contributors:
c9719c9

Hope that's fine.

No, that change is not correct, remove it. We want to strip trailing whitespace. You don't need trailing whitespace nor html tags (</br>) to write this tutorial.

[olehermanse]

Suggested change

	$ docker exec cfengine-host bash -c "/usr/local/sbin/cf-agent --bootstrap ${CFENGINE_HUB_IP}"
	docker exec cfengine-host bash -c "/usr/local/sbin/cf-agent --bootstrap ${CFENGINE_HUB_IP}"

[nickanderson]

Humm, this didn't work for me.

docker exec cfengine-host bash -c "/usr/local/sbin/cf-agent --bootstrap ${CFENGINE_HUB_IP}"
bash: line 1: /usr/local/sbin/cf-agent: No such file or directory

[me-coder]

Yeah, that's because we miss to read

Rest of the installation steps remain the same as for cfengine-hub.

I've removed this and added granular steps instead.

After the fix

cfengine$ docker exec cfengine-host bash -c "/usr/local/sbin/cf-agent --bootstrap ${CFENGINE_HUB_IP}"
  notice: Bootstrap mode: implicitly trusting server, use --trust-server=no if server trust is already established
  notice: Trusting new key: MD5=e5da40ee8037819f033e972d0fa24bcf
R: Bootstrapping from host '172.17.0.2' via built-in policy '/var/cfengine/inputs/failsafe.cf'
R: This autonomous node assumes the role of voluntary client
R: Updated local policy from policy server
R: Triggered an initial run of the policy
R: Restarted systemd unit cfengine3
  notice: Bootstrap to '172.17.0.2' completed successfully

While working on this part I realized that the Dockerfile and docker compose based approach is much efficient and faster as the installation happens only once.
However, for understanding sake, we should maintain this approach for deploying containers individually as well.

[nickanderson]

@me-coder thank you for this contribution. Overall it's quite a nice addition. Looking forward to having this in the docs.

[nickanderson]

I don't know of any other place we reference ubi images. Might be worth some description of what a ubi9 image is.

Red Hat Universal Base Images (UBI) are OCI-compliant container base operating system images with complementary runtime languages and packages that are freely redistributable.

[me-coder]

Added these references:

• RedHat Universal Base Image (UBI)
• Using the UBI init images
• ubi9-init repository

[nickanderson]

Humm, this didn't work for me.

docker exec cfengine-host bash -c "/usr/local/sbin/cf-agent --bootstrap ${CFENGINE_HUB_IP}"
bash: line 1: /usr/local/sbin/cf-agent: No such file or directory

[nickanderson]

Suggested change

	$ docker compose -f compose.yaml --verbose up -d
	docker compose -f compose.yaml --verbose up -d

[nickanderson]

I get an error running this.

validating /tmp/test/compose.yaml: services.cfengine-host.depends_on must be a list

[me-coder]

Yes, there was an indentation issue in the config.yaml. I've fixed it.
Also, added a linting step for Dockerfile and compose.yaml to capture such issues better,

[nickanderson]

@olehermanse Perhaps this should be re-titled to Installing Enterprise using disk image Or actually, maybe we need to drop this page completely. I don't see that we are still publishing a disk image since CoreOS is died (and now it's resurrected under Fedora https://fedoraproject.org/coreos/ ).

[me-coder]

Hi @olehermanse, @nickanderson,
Thank you for the detailed review.

I made the suggested changes and also a few enhancements to the document and force pushed it as a amended single commit.
I'm not sure if the suggested commits were supposed to be incorporated or were just markers for the review suggestions. (unaware of the rules being followed for this project).

I submitted a single commit as I always feel it's cleaner, could be fast-forwarded and there were changes which I could easily edit as a batch in VSCode editor.

Kindly re-consider the review with the applied changes.

- @me-coder