dshackle 0.79.10's beacon health validator (GET /eth/v1/node/health via
GenericSingleCallValidator) times out after 5000ms on the spec-compliant
empty-body 200 that nimbus returns, marking the upstream UNAVAILABLE in a
flap loop; live requests routed during flap windows fail 'Source was empty'.
This is the root cause behind dRPC's 617k failed validators POSTs complaint
(2026-07-09). Reproduced + workaround verified on an isolated dshackle
instance on de-14. Head tracking still governs availability.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
rob
a8655586db