Hostname validation backoff schedule

After you create a custom hostname, Cloudflare has to validate that hostname.

Attempts to validate a Custom Hostname are distributed over 7 days (a total of 75 retries). The function that determines the next check varies based on the number of attempts:

• For the first 10 attempts:

now() + min((floor(60 * pow(1.05, retry_attempt)) * INTERVAL '1 second'), INTERVAL '4 hours')

• For the remaining 65 attempts:

now() + min((floor(60 * pow(1.15, retry_attempt)) * INTERVAL '1 second'), INTERVAL '4 hours')

The first 10 checks complete within 2 minutes and most checks complete in the first 4 hours. The check back off is capped to a maximum of 4 hours to avoid exponential growth. The back off behavior causes larger gaps between check intervals towards the end of the back off schedule: