fix: switch HA NLB to internal scheme to fix hairpin routing#760
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ArangoGutierrez merged 1 commit intoNVIDIA:mainfrom Mar 31, 2026
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) The internet-facing NLB resolves to a public IP. When control-plane nodes connect to it after kubeconfig switchover, the hairpin routing (node → IGW → NLB → same node) is not supported by AWS NLBs, causing i/o timeouts on port 6443. Switch to an internal NLB which gets a private VPC IP, routing traffic directly within the VPC. Also remove the NLB DNS propagation wait since internal NLBs resolve immediately via VPC DNS. Fixes NVIDIA#746 Signed-off-by: Carlos Eduardo Arango Gutierrez <eduardoa@nvidia.com>
This was referenced Mar 31, 2026
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Summary
dial tcp ...:6443: i/o timeoutin HA clustersRoot Cause
When a control-plane node connects to the NLB via its public DNS after kubeconfig switchover, the packet goes node → IGW → NLB → same node. AWS NLBs don't support this hairpin routing, so the connection times out.
Test plan
cluster && haE2E test passes (post-merge)go build ./...cleanFixes #746