Hi @jume,
Here’s what the Validation Authority (VA) logged from our side for this attempt at 28/11/17 21:14:50. Recall that we perform validations from multiple vantage points for the staging environment. There are three remote VAs and one primary VA. For this example we’ll call the remote instances RVA_1 through RVA_3 and PVA_1 for the primary instance.
- 21:15:12 - RVA_1 starts a HTTP-01 validation
- 21:15:12 - RVA_2 starts a HTTP-01 validation
- 21:15:12 - RVA_3 starts a HTTP-01 validation
- 21:15:12 - RVA_1 registers a successful validation
- 21:15:12.467314 - PVA_1 starts a HTTP-01 validation
- 21:15:17 - RVA_2 times out - note that 21:15:17 - 21:15:12 = 5 seconds - the expected timeout.
- 21:15:17 - RVA_3 times out
- 21:15:17.719444 - P_VA1 times out.
Since three of the four validations timed-out, the overall validation is declared a failure due to timeout.
There’s no mystery from my side - it seems definitive that your challenge server is timing out on some (if not all!) of the challenge requests.
I hope this information makes it possible for you to figure out the timeout.