Resolving "401 Unauthorized Error: Unable to authorize VMware Aria Operations/vCenter Server API" in vCenter Plugin

Products

• VMware vCenter Server

Issue/Introduction

When attempting to load the VMware Aria Operations plugin within the vCenter UI, the plugin fails to load. The user sees a "401 Unauthorized Error."

The specific error message is:

401 unauthorized error: unable to authorize VMware Aria Operations/vCenter Server API with provided credentials

Environment

• VMware Aria Operations 8.x (formerly vRealize Operations)
• VMware vCenter Server 8.x

Cause

This is a general authentication error indicating that the Aria Operations plugin cannot communicate with the Aria Operations appliance or vCenter. There are a few distinct known causes for this failure, which are resolved in different ways.

Resolution

Table of Contents

• Scenario 1: Issue with Adapter Configuration or SSL Certificate
• Scenario 2: Issue with Global Settings or User Permissions
• Scenario 3: Issue with DNS Resolution

Please review the scenarios below and select the article that best matches your situation.

Scenario 1: Issue with Adapter Configuration or SSL Certificate

This error may occur if the vCenter Adapter Instance in Aria Operations is misconfigured, in a "Not Collecting" state, or has invalid credentials. This often happens after an SSL certificate is replaced on vCenter or if the adapter's test connection fails.

See KB 394585: ERROR: "401 unauthorized error: unable to authorize VMware Aria Operations/vCenter Server API with provided credentials"

Scenario 2: Issue with Global Settings or User Permissions

This error can be caused by a specific setting in Aria Operations and incorrect user permissions in vCenter:

• The Allow vCenter users to log in from vCenter clients setting is deactivated in Aria Operations Global Settings.
• The user's role in vCenter is missing the required Extension and vRealize Operations Read Only Role permissions.

See KB 376942: 401 unauthorized error : unable to authorize VMwareAria Operations/vCenter Server API with provided credentials

Scenario 3: Issue with DNS Resolution

This error can be caused by a network-level DNS failure, where the Aria Operations appliance cannot properly resolve the FQDN or IP address of the vCenter server. This can be verified by checking the unicorn.log file for Temporary failure in name resolution.

See KB 376661: Error "01 Unauthorized Error" is seen while accessing Aria Operations Plugin in vCenter