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Network L5 NETWORK-005 · 27 min

Only certain gRPC requests intermittently fail due to an MTU mismatch

Tracks MTU and segment size in a situation where small requests work but only large requests break in the middle.

NetworkPlatform ReliabilityLevel 5Pro27 min
Scenario

A scenario that narrows down the root cause, centered on checking the packet size together with the network path constraints, in the situation of only certain gRPC requests intermittently failing due to an MTU mismatch.

What to check first
  • Identify the primary failure signal in the Transport Debug scenario.
  • Separate visible symptoms from the underlying technical dependency.
  • Describe the safest recovery path and the follow-up prevention work.
Checking checklist
  1. Summarize the current impact and the last known change.
  2. Collect direct evidence from logs, runtime state, and configuration before changing anything.
  3. Separate immediate recovery from permanent prevention work.
Recovery and prevention

Choose the smallest safe recovery action first, then record the prevention work that reduces repeat incidents.

Questions worth viewing together
Why do MTU issues often appear only on specific requests?

Small packets succeed while larger gRPC or TLS records trigger fragmentation behavior and expose the mismatch.