Add ServiceLB support for PodHostIPs FeatureGate

[brandond]

Proposed Changes

Add ServiceLB support for PodHostIPs FeatureGate

If the feature-gate is enabled, use status.hostIPs for dual-stack externalTrafficPolicy=Local support.

At the moment, we are only able to advertise the address of the primary address family for services with externalTrafficPolicy=Local, as the downwards API does not expose both dual-stack host addresses.

Waiting on:

• Tidy functions and add support for comma-separated lists klipper-lb#60

Types of Changes

Enhancement

Verification

Start dual-stack k3s server with:

k3s server \
  --cluster-cidr=10.42.0.0/16,2001:cafe:42::/56 \
  --service-cidr=10.43.0.0/16,2001:cafe:43::/112 \
  --kubelet-arg=feature-gates=CloudDualStackNodeIPs=true,PodHostIPs=true \
  --kube-apiserver-arg=feature-gates=CloudDualStackNodeIPs=true,PodHostIPs=true \
  --controller-manager-arg=feature-gates=CloudDualStackNodeIPs=true,PodHostIPs=true \
  --kube-cloud-controller-manager-arg=feature-gates=CloudDualStackNodeIPs=true,PodHostIPs=true

Testing

Linked Issues

• Use status.hostIPs for ServiceLB pods #8823

User-Facing Change

Further Comments

[codecov]

Codecov Report

Attention: 11 lines in your changes are missing coverage. Please review.

Comparison is base (3f23723) 46.74% compared to head (4d67133) 49.88%.

Files	Patch %	Lines
pkg/cloudprovider/servicelb.go	26.66%	11 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8917      +/-   ##
==========================================
+ Coverage   46.74%   49.88%   +3.14%     
==========================================
  Files         150      150              
  Lines       15837    15849      +12     
==========================================
+ Hits         7403     7907     +504     
+ Misses       7232     6687     -545     
- Partials     1202     1255      +53     

Flag	Coverage Δ
e2etests	47.16% <36.36%> (?)
inttests	43.30% <26.66%> (-0.98%)	⬇️
unittests	18.13% <0.00%> (-0.03%)	⬇️

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