ESXi standalone root password not working due to account lockout

Products

• VMware vSphere ESXi

Issue/Introduction

VMware vSphere ESXi. The root password for a standalone ESXi host fails to authenticate. Users are unable to log into the ESXi host via the Direct Console User Interface (DCUI), SSH, or the VMware Host Client using known correct credentials.

Environment

VMware vSphere ESXi 8.0.x

Cause

The root account was temporarily locked out by the security daemon due to excessive consecutive failed login attempts.

Resolution

 

1. Identify the source of the excessive failed login attempts (e.g., automated scanning tools, outdated scripts, or unauthorized access attempts) and stop the process to prevent recurring lockouts.

2. Wait for the configured account lockout duration to expire (by default, ESXi locks accounts for 15 minutes after 5 to 10 failed attempts, but this may extend up to 30 minutes depending on configuration).

3. Attempt to authenticate to the ESXi host again using the correct root password.