Skip to content

Guide

ISO Settings

Guide 3 min read

This page explains the global ISO image whitelist that controls which ISO images customers may mount on their Hetzner Cloud servers. It is written for WHMCS administrators managing Cloud catalog policy.

Menu: Addons → Hetzner Data Center Core → Cloud → ISO Settings

ISO settings

Purpose

ISO Settings controls which ISO images customers may mount in the client area. This is a global catalog policy that applies to all Cloud products. Combine it with the per-product ISO Images toggle in Product Settings to hide ISO mounting entirely for specific products.

Page sections

Refresh bar

Control Behavior
Refresh from Hetzner API Loads the ISO list from the API and updates the last-refreshed timestamp
Last refreshed Display only — does not change the whitelist

x86 ISO images

Table of ISOs returned for architecture x86 (includes architecture-tagged x86 ISOs).

Column Description
Checkbox Include this ISO in the whitelist
ISO Name
Architecture x86, arm, or custom (no architecture field)
Description Hetzner's description

Include custom ISOs (no architecture) — when checked, user-uploaded ISOs without an architecture field are allowed for x86 servers.

ARM ISO images

Same layout for ARM (cax* servers), with a separate Include custom ISOs (no architecture) toggle.

Save as default

Saves the whitelist to cloud.iso_catalog.enabled as JSON:

json
{
  "enabled_x86": ["12345", "67890"],
  "enabled_arm": null,
  "include_custom_x86": true,
  "include_custom_arm": false
}
enabled_* value Meaning
null All architecture-compatible ISOs allowed (all boxes checked)
[] None allowed
["id", ...] Only the listed ISO IDs are allowed

How filtering works in the client area

  1. Server architecture is derived from the server type (x86 vs arm).
  2. The API's ISO list is filtered by architecture (plus optional custom ISOs).
  3. The admin whitelist from this page is applied.
  4. The per-product ISO Images toggle may block the page entirely.

Customers see the resulting filtered list when mounting an ISO in the client area.

ISO images available to clients

Workflow

  1. Click Refresh from Hetzner API after uploading new ISOs in Hetzner Console.
  2. Uncheck any ISOs you do not want customers to mount.
  3. Adjust the custom-ISO toggles if you use private ISO uploads.
  4. Click Save as default.

Settings reference

Friendly name System name Type Default
Enabled x86 ISO whitelist cloud.iso_catalog.enabled.enabled_x86 array or null null (all allowed)
Enabled ARM ISO whitelist cloud.iso_catalog.enabled.enabled_arm array or null null (all allowed)
Include custom x86 ISOs cloud.iso_catalog.enabled.include_custom_x86 yes/no No
Include custom ARM ISOs cloud.iso_catalog.enabled.include_custom_arm yes/no No

Troubleshooting

Problem Fix
Empty tables Configure the Cloud API Token
Customer does not see an ISO that should be available Refresh the catalog; check the whitelist and architecture filter
ISO is hidden from the list but mounting still works elsewhere Disable the ISO Images toggle in Product Settings for that product