Build a tool / github action to double check new node IPs aren't duplicates

[StevenBarre]

Describe the issue When adding new nodes with dhcp stuff, we need to double check that we aren't adding duplicate IPs. https://github.com/bcgov-c/rhcos-ignition-builder/pull/120

What is the Value/Impact? Prevent duplicate IPs in DHCP config

What is the plan? How will this get completed? Can we create a github action to lint PRs and alert if there are duplicate IPs in the inventory files

Identify any dependencies None

Definition of done

• [ ] Some way to detect duplicate IPs in inventory files before they go live.
• [ ] Create documentation
• [ ] Deliver a techtalk on github actions

[StevenBarre]

Not sure how we'll be able to detect duplicates with IPs not listed in the INV files?

[vivekratan88]

https://blog.ktz.me/check-for-duplicate-items-in-a-list-with-ansible-using-a-custom-filter/

[tbaker1313]

In the inventory files, the ip addresses are in the line containing 'ip:' so we can extract that data and feed it to awk something like this:

grep -R "ip:" inventory/host_vars/* | awk -F ':' '{if($3 in x){if(x[$3]) print x[$3]; print;x[$3]=""} else x[$3]=$0}'

The one issue here is that klab2 and emerald share a bootstrap ip address - could be filtered out with an inverse grep if desired.

[tbaker1313]

Had to try another approach to this as the last effort didn't yield a working result on the first test. Added a new workflow to test and am attempting to determine why the second task isn't running the way I think it should.

[tbaker1313]

Created a new repo for testing https://github.com/tbaker1313/test-actions