Recovering from a Lost ESX Root Password in ESX 3.5

Information

Title: 

Recovering from a Lost ESX Root Password in ESX 3.5

Author(s): 

Xtravirt (Paul Davey)

Target Audience: 

Technical - Novice

First Published: 

2 March 2009

Products: 

VMware ESX

UID: 

XD10003

Provides guide on how to reset the Root password on a VMware ESX 3.5 server.

Help! I've lost my root!

1.0 Introduction

This Xtravirt hot tip provides information on how to reset the Root password in VMware ESX 3.5.

Without the Root password it is impossible to carry out certain tasks. Even with a local user account although you may be able to log in to the console, without knowing the Root password, but you won’t be able to elevate privileges (SU or SUDO) successfully and adequately manage the server.

2.0 Pre-Requisites

• If the host is part of a cluster, vMotion your VM’s off the host then power down the ESX host
• If the host is standalone, power off running VM’s and then shut down the ESX host
• You will need to be at the ESX console to perform the following actions – an SSH connection cannot be used. Therefore connect directly to the server via KVM or make use of remote management cards such as HP iLO, Del DRAC or your server vendor’s equivalent

3.0 Resolution – Resetting the Root password

A lost Root password cannot be recovered, however it can be reset. The process below outlines how to do this.

1. Power on the host server. When the ESX bootloader selection screen appears, press a to allow you to modify kernel arguments

2. Type single to add the single argument to the kernel arguments and then press enter

3. The host server will now boot

4. Once the host server has booted, you will be presented with a prompt such as sh-2.05b#. At the prompt enter the command passwd and press enter

5. Enter the new Root password. Retype the new password at the prompt. Once changed successfully the all authentication tokens updated successfully message will appear

6. Reboot the host server by typing reboot at the prompt and pressing enter

4.0 General Information

• If the ESX host is managed by vCenter (formally VirtualCenter), you will need to provide the new Root password credentials again in vCenter to reconnect it
• For information on changing the Root account password for previous versions of ESX servers (2.x and 3.x), see the following VMware KB article http://kb.vmware.com/kb/1317898

References

References: 

VMware http://kb.vmware.com/kb/1317898