Problem description

Customers may encounter issues where the Nutanix backup proxy is unable to authenticate with Prism Central (PC) or Prism Element (PE) using the configured credentials. This results in:
- Backup job failures due to user credential errors.
- Proxy deployment failures when using the same credentials.

Cause

This issue occurs when:

The credentials provided for the backup proxy are incorrect.
The Nutanix user account is locked out due to multiple failed authentication attempts.

Symptoms

Backup jobs fail with authentication-related errors.
Proxy deployment cannot proceed due to credential validation errors.
Errors appear in the following logs:
- Backup proxy log: /var/log/Phoenix/main_service.log
- Nutanix CVM log: ~/data/logs/prism_gateway.log

Traceback

Typical error traces include authentication failures in the backup proxy logs and user lockout errors in the Nutanix CVM logs.

less /var/log/Phoenix/main_service.log tail -F ~/data/logs/prism_gateway.log

Resolution

Follow the steps below to validate and resolve the credential issue:

1. Validate Credentials via Prism

2. Verify Credentials via CLI / API

Retrieve the VM UUID using Nutanix CLI:

ncli vm list name=<vm name> | grep 'Uuid' | grep -v Host | cut -d':' -f2 | awk 'NF{$1=$1;print}'

Query VM details using curl:

curl -kX GET -u <user>:<password> --header "Accept: application/json" \ 'https://<PC or PE IP or FQDN>:9440/api/nutanix/v3/vms/<VM UUID>' \ -H 'accept: application/json' -H 'X-Nutanix-Client-Type: ui'

3. Review Logs for Authentication Errors

On the backup proxy:
```
less /var/log/Phoenix/main_service.log
```
On Nutanix CVM:
```
tail -F ~/data/logs/prism_gateway.log
```

4. Reset Locked Nutanix User Account (if applicable)

Reset the account using:

allssh sudo faillock --user admin --reset

Prevention (Best Practices)

To avoid future issues:

Create a dedicated Nutanix API user for Druva backups (do not share across multiple tools).
Assign minimum required roles/permissions.
Monitor prism_gateway.log for failed login attempts.
Avoid using default admin accounts; configure a service account with strong password rotation policies.
Periodically validate credentials with an API call to confirm account activity.

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