Why not continue in SAML configuration with NameID as unspecified - #3 by AjitR ?
Provided SAML response is not valid for realm saml/saml1 (Caused by ElasticsearchSecurityException[SAML content is in-response-to _8ca119eb20c3a44e54c0edba4538500bf62b3879 but expected one of [] ]
This should only be a transient error. Is it reproducible on your side in a new incognito browser window ?
- Please enable trace logging as described in Common SAML issues | Elasticsearch Guide [8.11] | Elastic
- Describe to us what you are doing in the browser ( which URL do you navigate to , what happens next etc. ) to get this error, or even better capture a HAR from your browser.