Bug ID 1934201: "Failed to get auth" error occurs when creating or renewing a domain through LetsEncrypt Third Party CA Management

Last Modified: Sep 02, 2025

Affected Product(s):
BIG-IQ ADC(all modules)

Known Affected Versions:
8.3.0

Opened: May 03, 2025

Severity: 3-Major

Symptoms

When creating or renewing a domain within the LetsEncrypt Third Party CA Management, an error occurs which states: """ Error on server request 1. The system returned an unexpected error (400 Bad Request). Failed to get auth: """ With an instrumented BIG-IQ JAR file, response from LetsEncrypt ACME server would be a 503, which includes a 'Retry-After' HTTP header.

Impact

When renewing or creating a new domain, BIG-IQ sends a newOrder request that contains all the domains managed in the LetsEncrypt configuration into the request's "identifiers" field. When LetsEncrypt sends back a response, that response contains >= 20 new-nonce URLs. BIG-IQ then sends >= 20 new-nonce requests towards the ACME server, resulting in the LetsEncrypt limits being reached. See https://letsencrypt.org/docs/rate-limits/.

Conditions

Domains managed is equal or greater than 20 within the same LetsEncrypt configuration group.

Workaround

Limit the domains managed in a single LetsEncrypt CA Management group to less than 20 domains.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips