`nmcli` not working on Raspbian

[pdemarti]

Context

First of all, thank you for your excellent blog and for this automated template! I wasn't aware of several of the techniques and packages you describe -- it was awesome for me to discover Pi-hole, Cloudflare, Caddy and Ansible.

I've been spending a few hours trying to get the step:

Sit back and wait until I have a fully configured PiHole running in about 5-10 minutes.

to work... ;-)

So far, I've learned a lot, and found a few issues and tricks in the ansible config. I hope you don't mind if I address them in separate tickets. As a preview, so far:

• (bug, this issue): nmcli is not working out of the box on Raspbian.
• (feature): using Bitwarden instead of 1Password for secrets management.
• (bug): GPG error when trying to sign the docker repo.
• (bug): incorrect usage (perhaps as a result of a change?) of community.general.ufw ("ERROR: Bad port 'SSH'").
• (needs clarification): what is the content/source of your private repo git@github.com:benbalter/pi-hole.git? Is it a private fork of the official docker-pi-hole with some config changes, or something else entirely (note to self: to make a private fork, see e.g. here)?
• (needs clarification): more details about the overall procedure (e.g.: how to set up the Raspberry Pi to the point when we can ssh into it and start running the ansible playbook).

nmcli not working out of the box on Raspbian

Symptoms

When running ansible-playbook playbook.yml --inventory hosts.yml, I get:

fatal: [192.168.1.2]: FAILED! => {"changed": false, "msg": "Error: unknown connection 'eth0'.\n", "name": "eth0", "rc": 10}

It appears that nmcli is not working out of the box on Raspbian. See e.g. here.

A potential fix is this gist:

# already done in the playbook
sudo apt update
sudo apt install network-manager

# new steps
sudo apt purge openresolv dhcpcd5
sudo reboot

Steps to reproduce the behavior

1. Clone this repo.
2. ssh to a freshly flashed Raspbian 10 Raspberry Pi.
3. adjust the image and set up the RPi to be reachable by ssh (see below)
4. ansible-playbook playbook.yml --inventory hosts.yml

Note: Adjustments to fresh image When I flash a new Raspberry image, I always tweak the content of the SD card as it is still in the card reader:

1. mount the boot and rootfs partitions locally, say in /Volumes (Mac) or /media/$USER/ (Ubuntu); whatever the exact location, below I use $mp;
2. create wpa_supplicant.conf under $mp/boot/ (see e.g. here)
3. enable ssh (touch $mp/boot/ssh);
4. mkdir -p $mp/rootfs/home/pi/.ssh and cat ~/.ssh/id_rsa.pub >> $mp/rootfs/home/pi/.ssh/authorized_keys.
5. put the SD card in the Raspberry, power it on
6. find the address that was given by the router
7. ssh pi@that-address
8. set a static IP address, see e.g. here.

Expected behavior

I expect nmcli to be operational and work as the ansible playbook intentended.

[pdemarti]

@benbalter : were you able to actually get nmcli to work at all? I've tried quite a few things, no cigar. I put the question to SO, but so far it hasn't prompted much interest...