Cluster Rebalancing

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On-demand rebalance

# Dry-run: see what would change
opsctl rebalance -p <cluster>

# Execute with rolling drain (no double capacity needed)
opsctl rebalance --rolling-drain -p <cluster>

# Replace all nodes (K8s version upgrades)
opsctl rebalance --rolling-drain --replace-all -p <cluster>

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Execution strategies

• Provision-first (default): creates replacement VMs, waits for them to be ready, then drains old nodes. Requires temporary double capacity.
• Rolling drain: drains nodes in batches of 5–10, deletes them, and lets the scaler provision right-sized replacements. ~0.5 min/node, no double capacity.

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When to use

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Key features

• Cost comparison — before/after cost analysis per node.
• Crash recovery — full state persisted in ConfigMaps; a run resumes on controller restart.
• Maintenance windows — scheduled deep consolidation including fragile pods.
• Fragile pod detection — single-replica workloads, no-PDB workloads, and OrderedReady StatefulSets are handled carefully.
• PDB-respecting eviction — all pod movement goes through the Kubernetes Eviction API.

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Dashboard