You'll learn to explain what an ADOM contains, decide how many you need, and enable and create ADOMs safely.
Technical definition
ADOM (administrative domain) is a separate management space inside FortiManager. Each ADOM has its own devices, policy packages, objects and templates, tied to one FortiOS version.
One FortiManager, several groups of firewalls
A managed service provider looks after three customers. A company has HQ firewalls on FortiOS 7.6 and a lab on 7.4. Without separation, every administrator sees every device and a single object list grows into a mess. ADOMs give each group its own space.
One space and several ADOMs
On small screens, swipe sideways or focus the diagram and use the arrow keys.
Use ADOMs to separate customers or firmware versions.
Each ADOM is its own management space
On small screens, swipe sideways or focus the diagram and use the arrow keys.
An ADOM holds devices, policy packages, objects and templates. Objects in one ADOM are not visible in another.
What an ADOM contains
The devices assigned to it
Its policy packages and the objects they use
Its templates and scripts
A FortiOS version that matches its devices
Administrators can be restricted to specific ADOMs, so a team sees only the firewalls it runs.
What an ADOM contains
On small screens, swipe sideways or focus the diagram and use the arrow keys.
Changes in one ADOM do not affect another.
Enable and create ADOMs
config system global
set adom-status enable
end
Enabling ADOMs reconfigures how FortiManager is organised and signs administrators out. Existing devices go to the root ADOM. Choose this on a new system rather than a busy one.
Plan the ADOM layout first
Moving devices between ADOMs later takes work and can change policy and object names. Decide the split by customer, region or firmware version before adding many devices.
Create further ADOMs in System Settings, choosing a name and the FortiOS version. Put each FortiGate in the ADOM whose version matches it.
Enable ADOMs
On small screens, swipe sideways or focus the diagram and use the arrow keys.
Pick the right version for the devices inside.
How many ADOMs?
Few or many ADOMs
On small screens, swipe sideways or focus the diagram and use the arrow keys.
Use as few as meet your needs.
How many ADOMs?
On small screens, swipe sideways or focus the diagram and use the arrow keys.
Each item on the left, with what it means on the right.
Check your understanding
Predict · scenario 1
A company has FortiGates on 7.6 and 7.4. How does FortiManager keep their settings straight?
Predict · scenario 2
Which command enables ADOMs?
Predict · scenario 3
Where do existing devices go when ADOMs are enabled?
Further reading in Fortinet's documentation
Links open the named page in Fortinet's documentation (checked 19 October 2026). RouteLearn is an independent educational resource, not affiliated with or endorsed by Fortinet. Fortinet, FortiGate, FortiOS, FortiManager and FortiGuard are trademarks of Fortinet, Inc. Example output on this page is illustrative.
FAQ
Why does an ADOM have a version?
Different FortiOS releases have different options and defaults. An ADOM written for 7.6 offers 7.6 settings, so devices in it should run a compatible release.
Can I share an object between ADOMs?
Not directly. Each ADOM has its own objects. Use a global database where available, or recreate and import what you need.
Can ADOMs be turned off again?
Moving to a single ADOM later is hard, so decide before you enable them. Check the documentation for your release before changing it.