Change kube-vip LB IP pool logic

[vxav]

Current setup

• We specify a globalippool in the cluster values: here
• We create an ipadressclaim using this pool which blocks a single ipaddress: here
• We collect the IP from the cluster and edit the CPI helmrelease to create a one-IP pool with cidrGlobal:: here

I don't get why we do that. It means we have a 10-IPs IPAM pool in the MC but the WC as a 1-IP pool 🤷. So the first load balancer will work fine (most often nginx) while subsequent LBs will be stuck on pending.

Proposition
Collect the actual IP pool from the LB IP pool in the MC.

> kg globalinclusterippools.ipam.cluster.x-k8s.io cassino-svc-lb-ips -ojsonpath='{.spec.addresses[0]}'
10.109.147.221-10.109.147.230

And patch the Helmrelease with a range-global instead.

EDIT: Actually now I remember. We use an IPaddressclaim to block the IP on the MC side. If we set a range in the WC it could (potentially) be set in multiple WCs.
Ideally we would need something like ipaddressrangeclaim or create a claim for each IP. Somehow.
In the meantime, the solution Could be:

• Add an ipAddressClaim in the MC and add an interface in the cluster chart to add the IP to the CPI helmrelease.
• Add a field in the cluster values to specify the number of IPs to take from the global pool for the WC pool so we can iterate to create that number of ipaddressclaims and patch the cpi helmrelease with the joined IPs.

[vxav]

Untested : giantswarm/cluster-vsphere#266

[anvddriesch]

I made some small changes to the PR and now several ips can be assigned.

[anvddriesch]

the standard test was green when I ran it last week. However, as of now all providers fail and the reason is related to some already-exists issue with cert exporter configmaps in the default-apps.
This leads me to believe that its related to the default apps changes still being made.

[vxav]

Thanks a lot! I'll test this manually as the E2E tests won't be testing what we're changing here

[anvddriesch]

I created some random lb services on a test cluster and we see the expected behavior.
Three single ip cidrs are added to the helm relesase for lb ip space.
Creating four lb services in a row resulted in these three ips being assigned to the first three and then the fourth one not getting an assignment.

[vxav]

Ok that's good. I think for now we can stick with this being an immutable field and keep 3 as default like you suggested here as it would be more work than worth it to make it a dynamic value. wdyt?

[anvddriesch]

changes were merged