Reset a Lost ESXi Root Password

Recovering a Lost VMware ESXi Root Password

VMware doesn’t provide a way to recover the original root password on an ESXi host. That’s stated plainly in Broadcom’s own knowledge base: if you’re locked out and the host isn’t managed by vCenter, reinstalling is the only officially supported path. That sounds harsh for a single home lab or branch-office host, which is exactly why a Linux-live-CD trick for clearing the password hash directly on disk has circulated in sysadmin circles for over a decade. It still works — on older ESXi builds. On ESXi 7.0 Update 3 and every 8.x release, VMware encrypted the configuration archive that trick relies on, and the plain version of it no longer does anything.

This covers both: the official recovery paths worth trying first, the classic method for hosts still running an older ESXi build, and what actually changed on newer versions so you’re not following a decade-old guide against a host it was never written for.

How do you reset a lost ESXi root password?

If the host is managed by vCenter with an Enterprise Plus license, reset it through Host Profiles or PowerCLI without touching the host directly. If it’s standalone, VMware’s only supported option is reinstalling ESXi while preserving the VMFS datastore, which keeps your VM files intact even though the host configuration is rebuilt. An unsupported but widely used alternative exists for standalone hosts: boot a Linux live environment, mount the ESXi boot partition, and clear the password hash in /etc/shadow. This works cleanly on ESXi 5.x through roughly 7.0 Update 2. On ESXi 7.0 U3 and 8.x, the configuration archive is encrypted, and the same steps won’t get you in.

Try the supported path first

Before booting anything from a USB stick, check which of these applies:

• Host is in vCenter, Enterprise Plus licensed: Extract a Host Profile from a healthy host (or build one), edit the root password field in that profile, and attach it to the locked-out host.
• Host is in vCenter, no Host Profile license: Reset it with PowerCLI instead — Get-EsxCli against the host object lets you set a new root password without ever logging into the host itself.
• vSphere Configuration Profiles enabled instead of classic Host Profiles: the same reset is available through Configuration Profiles.
• Standalone host, no vCenter: reinstall ESXi and reattach the existing VMFS datastore. Back up the host configuration first if you can still reach it (DCUI, SSH) — even a failed login attempt doesn’t mean the configuration export tools are unreachable if you have another admin account or SSH key that still works.

If none of those apply — no vCenter, no other account, no working backup — the live-CD method below is the realistic option, with the caveat that it’s explicitly unsupported and version-dependent.

The classic method (ESXi 5.x through ~7.0 U2)

This is the same approach that’s been documented for years, and it still works on hosts running an ESXi build old enough to predate encrypted configuration archives.

Confirm you’re actually locked out before starting — the DCUI will show Authentication failed / Invalid login or password if the credentials are wrong.

1. Shut down the host cleanly from the console if you can reach it at all, then power it back on. If you can’t authenticate anywhere, use the physical or remote console power controls to restart it.

2. Boot the host from a Linux desktop live image — Ubuntu Desktop and GParted Live both work; GParted Live is lighter if all you need is the partition tool.

3. Choose Try Ubuntu (or the equivalent “run without installing” option). You’re not installing anything on the host.

4. Open a terminal from the desktop search or applications menu.

5. Get root in the terminal with sudo -i, then list the disks with fdisk -l or lsblk to identify the ESXi boot device.

6. ESXi’s boot partitions are normally GPT, which older fdisk builds won’t parse cleanly. If that happens, open GParted instead to see the partition layout.

7. Mount the correct partition — typically sda5, one of ESXi’s two bootbank partitions — to a temporary directory: mkdir /mnt/esxi && mount /dev/sda5 /mnt/esxi.

8. Copy state.tgz out to a working directory and extract it. This produces local.tgz.

mkdir /tmp/work && cd /tmp/work
cp /mnt/esxi/state.tgz .
tar xzf state.tgz

9. Extract local.tgz in turn. This produces an etc directory containing the host’s configuration files, including shadow.

tar xzf local.tgzCode language: CSS (css)

10. Open etc/shadow in a text editor and find the root line. Delete the characters between the first two colons — that field holds the password hash. Leaving it empty gives root a blank password rather than a random one you’d still be locked out of.

vi etc/shadow

11. Repack etc into local.tgz, then local.tgz into state.tgz, and copy the result back to the mounted partition.

tar czf local.tgz etc
tar czf state.tgz local.tgz
cp state.tgz /mnt/esxi/

12. Unmount the partition, remove the live media so the host boots from local disk, and reboot.

umount /mnt/esxi
reboot

13. Once ESXi finishes booting, log in as root with no password.

14. Set a real password immediately, and store it somewhere your team can actually retrieve it next time — a password manager or sealed break-glass procedure, not a sticky note on the rack.

That last step matters more than it sounds. The entire reason this article exists is that someone lost the password once already.

Frequently Asked Questions

References

Broadcom — Methods to Recover the ESXi Host Root Password https://knowledge.broadcom.com/external/article/393496/methods-to-recover-the-esxi-host-root-pa.html

Broadcom — Reset Password for Root Account of ESXi Server Using PowerCLI https://knowledge.broadcom.com/external/article/376979/reset-password-for-root-account-of-esxi.html

William Lam — Recovering ESXi 7.x & 8.x Host After Forgetting or Losing Root Password https://williamlam.com/2024/10/recovering-esxi-7-x-8-x-host-after-forgetting-or-losing-root-password.html

Learn more: Greyed Out “Migrate” Button Issue in VMware vCenter and Its Solution