# Encountering an authentication error following the restoration of an Elasticsearch cluster from a Longhorn volume backup
**URL:** https://discuss.elastic.co/t/encountering-an-authentication-error-following-the-restoration-of-an-elasticsearch-cluster-from-a-longhorn-volume-backup/378047
**Category:** Elastic Cloud on Kubernetes (ECK)
**Created:** [May 12, 2025, 2:32pm UTC](https://discuss.elastic.co/t/encountering-an-authentication-error-following-the-restoration-of-an-elasticsearch-cluster-from-a-longhorn-volume-backup/378047 "2025-05-12T14:32:19Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@Anand\_Pradeep](https://discuss.elastic.co/u/Anand_Pradeep)
#### Post date: [May 12, 2025, 2:32pm UTC](https://discuss.elastic.co/t/encountering-an-authentication-error-following-the-restoration-of-an-elasticsearch-cluster-from-a-longhorn-volume-backup/378047/1 "2025-05-12T14:32:19Z")
Elastic seach is deployed on k8s env using elastic-operator. While trying to restore the old data using longhorn volume restoration method the pods came up and running, however there is an authentication error in the pod logs.
{"type": "server", "timestamp": "2025-05-06T16:14:15,351Z", "level": "WARN", "component": "o.e.x.s.a.RealmsAuthenticator", "cluster.name": "isna-es-cluster", "node.name": "isna-es-cluster-es-default-2", "message": "Authentication to realm file1 failed - Password authentication failed for elastic", "cluster.uuid": "WSR7bfC2RYW4Gx0isuWQ1w", "node.id": "pLbxXXoxQgK-MQL6JJYXeA" }
@team could you help on this.
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### Author:  [@pebrc](https://discuss.elastic.co/u/pebrc)
#### Post date: [July 4, 2025, 3:32pm UTC](https://discuss.elastic.co/t/encountering-an-authentication-error-following-the-restoration-of-an-elasticsearch-cluster-from-a-longhorn-volume-backup/378047/2 "2025-07-04T15:32:34Z")
When you restored the old data, you presumably restored it into a new cluster? Are you trying to use the old credentials from the previous cluster here?
If so, this is unlikely to work the credentials for the `elastic` user are stored in a Kubernetes secret that was probably deleted together with the old cluster.
You have to retrieve the new credentials as documented here [Accessing services | Elastic Docs](https://www.elastic.co/docs/deploy-manage/deploy/cloud-on-k8s/accessing-services#k8s-authentication)