PrivateLink cost optimization: reduce endpoint-hours, GB processed, and operational sprawl
PrivateLink is usually deployed for security and simplicity, but it can create a second networking bill if endpoint sprawl grows. The good news: the cost levers are simple and governable. This guide focuses on reducing endpoint-hours, preventing sprawl, and validating that the “private path” actually reduced your NAT and egress drivers.
The cost model (what to budget)
- Endpoint-hours ≈ endpoints × AZs enabled × hours/month
- Traffic processing (if applicable) = GB processed × $/GB
- Total = endpoint-hours + processing + any transfer that still applies
Tool: VPC interface endpoint cost calculator
1) Prevent endpoint sprawl (governance is the highest ROI)
- Define a standard endpoint set per environment (prod vs non-prod).
- Require ownership and lifecycle for each endpoint (who pays, why it exists, when to delete).
- Tag endpoints by team/service and alert on new endpoints without an owner.
- Delete endpoints created for migrations and experiments after the project ends.
2) Reduce endpoint-hours (the main lever)
Endpoint-hours grow with “count × AZs”. The best approach is to model 2–3 scenarios and pick the one that matches your availability requirements.
- Consolidate duplicates: avoid multiple endpoints for the same service per environment when one is enough.
- Right-size AZ coverage: compare 2-AZ vs 3-AZ footprints for cost and risk.
- Non-prod schedules: if non-prod isn’t used, consider deleting endpoints (and recreating when needed) instead of always-on sprawl.
3) Reduce GB processed safely (avoid “private traffic amplification”)
- Cache where safe: reduce repeated calls to the same endpoints.
- Fix retries/timeouts: incident windows can multiply calls and processed GB.
- Stop noisy polling: high-frequency health checks and polling can create a steady baseline.
4) Prefer the simplest private option when it exists
Private connectivity isn’t one-size-fits-all. In some cases, a gateway-style private path can be simpler than adding many interface endpoints. The practical rule: choose the option that removes the most NAT traffic with the least always-on footprint — then validate in billing.
Compare alternatives: NAT vs endpoints cost
5) Avoid transfer boundary surprises
Private traffic can still cross AZs/regions depending on routing and service placement. Validate locality and model transfer explicitly when architectures span AZs:
Validation checklist (after rollout)
- Confirm endpoint-hours match the intended footprint (no silent sprawl across AZs/environments).
- Confirm the expected NAT processed GB reduction actually happened.
- Check for shifted costs: cross-AZ transfer and internet egress lines.
- Verify reliability: endpoints used for critical paths should be monitored like production dependencies.