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FortiManager interview questions with evidence

Change window. A junior in ADOM PROD-IN clicks Install on policy package pkg_prod_in without Install Preview. FGT-IN-02 loses a VIP that was never in the ticket. The weak answer is “FortiManager pushed policy.” The strong answer names ADOM → policy package → device database → Install Preview → ADOM revision, quotes the preview diff, then restores from revision — not from a FortiGate reboot.

20 min read · L2 primary · 8 scenarios · 6-question quiz

Quick Answer

FortiManager interview questions and answers (2026) that also teach: ADOMs isolate devices and objects; a policy package is not the device database; Install copies ADOM objects into the device DB then diffs the live FortiGate; Install Preview and Policy Package Diff are the change-control evidence; ADOM revisions restore packages/objects/VPN console — not interfaces; shared objects blast every package in the ADOM that references them.

After this page you can

Say this out loud

I am in ADOM PROD-IN on FortiManager 192.0.2.10. Policy lives in package pkg_prod_in. Device-specific config lives in the device database for FGT-IN-01. Install copies ADOM objects into that device DB, diffs the live FortiGate, and pushes the delta. I do not click Install until Install Preview and Policy Package Diff match the ticket, and I create an ADOM revision first. FortiManager does not forward the user’s packet.

1. Ticket hook — Install without preview

Night shift. Checkout VIP on FGT-IN-02 (192.0.2.22) is gone. Last Task Monitor row is Install Policy Package & Device Settings for pkg_prod_in, ADOM PROD-IN. A junior “only added one firewall policy” on FGT-IN-01. They skipped Install Preview. The package is assigned to both firewalls. A shared address addr_hq_web was edited in the ADOM object database. No ADOM revision was created.

That is the interview. FortiManager is the writer, not the forwarder. A package install is a fleet change. Preview is the evidence. Revision is the rollback. Editing a shared object without Where Used is how one site’s fix becomes two sites’ outage.

Hero · who talks to whom
Admin workstation to a central FortiManager that fans policy into two ADOMs, each managing its own FortiGate
Notice: the admin never SSHs every FortiGate for policy. FortiManager writes. Each ADOM is a fence. The FortiGate still forwards the user packet after a successful install.
Hard words, once

ADOM — administrative domain; devices, packages, and objects are scoped here. Lab: PROD-IN vs PROD-US. Policy package — firewall / NAT / security-profile policy set assigned to installation targets; lab pkg_prod_in. Device database — full per-FortiGate config on FortiManager (interfaces, routing, system). Install — copy ADOM objects into the device DB, diff the live FortiGate, push the delta. Install Preview — CLI-style diff you read before Install. Policy Package Diff — package vs what is on the device. ADOM revision — snapshot of packages, objects, VPN console in that ADOM. Retrieve — FortiGate config → device DB. Import — device-DB policies → ADOM package. Auto-Update — FortiGate sends a local change into the device DB (default on). Workspace / Workflow — lock (or approve) so two admins do not collide.

2. Mental model: two databases, one ADOM

Interviewers mix FortiManager with “the firewall.” A FortiGate permits or denies the session. FortiManager stores two different configs and only the FortiGate enforces after Install succeeds. Empty Task Monitor plus a drop is a FortiGate / FortiAnalyzer ticket, not an ADOM ticket.

What FortiManager owns

ADOM membership, policy packages, shared objects, provisioning templates, the device database copy, Install Wizard, ADOM revisions, workspace locks. Central policy is a draft until Install finishes.

What the engineer owns

Which ADOM they are in, which package is assigned to which device, whether Preview matched the ticket, whether a shared object is referenced elsewhere, and which revision they can restore — before anyone clicks Install.

Path · ADOM → package → device DB → preview → install
Five-stage pipeline from ADOM through policy package, device database, preview, and install
Mood of the pipeline. Exact gates: correct ADOM, package assigned, Preview + Diff reviewed, Create ADOM Revision ticked, then Install. Artwork labels are not GUI strings.

Lab tree you should be able to draw cold:

3. Install order on FortiManager

Flowchart first. Recite this order; do not skip Preview.

Flow 1 · Install Policy Package & Device Settings
ADOM PROD-IN correct ADOM? pkg_prod_in ADOM database Copy → device DB FGT-IN-01 file Diff live FortiGate then push delta 1 Preview Install Preview CLI diff 2 Package Diff package vs device 3 ADOM revision Create ADOM Revision 4 Install or Schedule Install A push needs four ANDs — miss one and FGT-IN-02 still eats the change Correct ADOM · package assigned to that device · Preview/Diff match the ticket · revision created. Install copies ADOM objects into the device database first, then diffs the running FortiGate, then pushes the delta. Editor ≠ data path. Task Monitor is the install evidence. diagnose dvm device list is the sync evidence. FortiGate policy hit / FAZ is the packet evidence. Device Manager → Device & Groups → Install Wizard → Install Policy Package & Device Settings.

ADOM first. Package is a draft in the ADOM database until Install copies it into the device DB and the live FortiGate accepts the delta. Preview is not optional.

Flow 2 · Status ladder before you touch Install
Modified (yellow) changed on FortiManager Out of Sync (red) changed on the FortiGate Auto-Update device DB only Preview + Install FMG is source of truth Decide SoT first Install overwrites FGT · Import keeps it Not an Import package still stale Four operations — do not mix the arrows Retrieve: FortiGate → device DB. Import: device DB policies → ADOM package. Install: FortiManager → FortiGate. Auto-Update: unsolicited FortiGate → device DB. If FortiManager is source of truth, do not Import a rogue VIP — Preview, then Install. If the local change was approved, Retrieve then Import, then Install to clear flags. Device Manager → Device & Groups table: Config Status + Policy Package Status. CLI: diagnose dvm device list.

Modified is your uncommitted work. Out of Sync is theirs. Auto-Update updates the device database and leaves the policy package behind until you Import or overwrite with Install.

4. How to choose status, operation, revision

Three tables. Interviewers mix them. Keep the arrows separate: FMG→FGT, FGT→device DB, device DB→package.

Policy package status vs config status

ModifiedOut of SyncSynchronized / Imported
Where the change happened Policies or objects edited on FortiManager Policies or objects edited on the managed FortiGate Package and device agree (Imported = pulled in, not yet the same as installed forever)
Next move if FMG is SoT Install Preview → Create ADOM Revision → Install Preview, then Install to overwrite the local FortiGate change Nothing to push. Prove with diagnose dvm device list
Next move if FGT change was intended Do not Install yet — you will clobber your own ADOM edit Retrieve (if needed) → Import Policy → then Install to clear flags
Interview trap “Yellow means the FortiGate is down” “Out of Sync means retrieve and we are done” — package can still be stale “Green means the last ticket is in the running policy” — check revision + Task Monitor

Retrieve vs Import vs Install vs Auto-Update

OperationArrowChoose when
Install / Re-install ADOM objects → device DB → live FortiGate FortiManager is source of truth. Always Preview first.
Retrieve Live FortiGate → device database You need the running config in Device Manager (interfaces, routing, local edits).
Import Policy Device DB policies → ADOM policy package You want those FortiGate policies as the package. After first import, keep editing in Policy & Objects.
Auto-Update Unsolicited FortiGate → device DB (default enabled) Local GUI change lands in device DB. It is not Import. Package status can still be Out of Sync / Unknown.

ADOM revision vs device revision history

ADOM revisionDevice revision history
Where Policy & Objects → ADOM Revisions (also a checkbox on Install Wizard) Device Manager → device database → configuration revision history
What it stores Policy packages, objects, VPN console in that ADOM That FortiGate’s device-database config file
Restore puts back Packages / objects / VPN console — not interfaces, routes, HA Device settings for that unit — not the ADOM object database
Interview trap “Restore ADOM revision and the VIP interface comes back” “Device revision rewinds every package in the ADOM”

5. Do: preview, revision, then Install

Side A is scope. Side B is the Install Wizard. Side C is proof. One primary source per block.

  1. Side A — lock the ADOM and the blast radius

    Confirm the GUI ADOM is PROD-IN, not root and not PROD-US. List installation targets on pkg_prod_in. Run Where Used on any object you touched (addr_hq_web). If two admins might edit, lock the ADOM or the package (Workspace) or open a Workflow session. Source: FortiManager Admin Guide — ADOMs / Workspace.

  2. Side B — Install Wizard, Preview, revision, Install

    Device Manager → Device & Groups → Install Wizard → Install Policy Package & Device Settings. Select pkg_prod_in. Tick Create ADOM Revision and name it from the change ticket. Open Install Preview (download the text) and Policy Package Diff. If the diff shows a VIP/interface you did not ticket, stop. Then Install or Schedule Install. Source: Admin Guide — Installing policy packages and device settings.

  3. Side C — prove sync, then prove the packet

    Task Monitor must finish without validation errors. Device Manager: Config Status Synchronized, Policy Package Status Synchronized. CLI: diagnose dvm device listconf: in sync, pkg:[installed]pkg_prod_in. Then the original business test on the FortiGate (policy hit / FortiAnalyzer), not a green FMG icon. Source: Admin Guide — Checking device configuration status; Viewing policy package status.

https://192.0.2.10/ — Device Manager · Install Wizard
Training mock · not live

ADOM: PROD-IN · Device & Groups · Install Wizard

Install Policy Package & Device Settings

pkg_prod_in
FGT-IN-01, FGT-IN-02
Yes · CR-2026-0905-checkout
Off — after Preview

Field names from the 7.6/8.0 Install Wizard. Preview and Diff are optional in the GUI and mandatory in production. Create ADOM Revision is a checkbox on this same page — use it.

Lab proof — FortiManager CLI
diagnose dvm device list
# expect FGT-IN-01 / ADOM PROD-IN
# STATUS: dev-db: not modified; conf: in sync; cond: OK; dm: installed; conn: up
# vdom: root  pkg:[installed]pkg_prod_in

6. Runtime path after go-live

After Install, the FortiGate is the data path. FortiManager watches sync flags. A local FortiGate GUI edit triggers Auto-Update into the device database by default — the policy package can still show Out of Sync until you Import or overwrite with Install. Workspace lock is how two L2s do not silently merge objects. Global Database header/footer packages are the only intended leak across ADOMs.

Proof · cockpit
Operator reviewing an install-preview style diff and revision timeline on a NOC desk
Mood of the desk. Real proof is Install Preview text, Policy Package Diff, Task Monitor, ADOM revision ID, and diagnose dvm device list — not a green dashboard tile.

7. Eight interview scenarios

Q1 · Architecture — name the objects in order

Whiteboard. “Walk FortiManager from an admin click to a FortiGate that actually has the new firewall policy.” A junior draws User → FortiManager → App. What do you draw instead, and where is the decision enforced?

Direct answer
Draw ADOM → policy package → device database → Install Preview → ADOM revision / Install, then the FortiGate. The admin edits in ADOM PROD-IN. Package pkg_prod_in is ADOM-database policy. Install copies it into the device DB for FGT-IN-01, diffs the live box, pushes the delta. The FortiGate forwards or drops the user packet. FortiManager does not sit on the SYN.
Why production cares
If you cannot point at the object that is wrong, you will retrieve when you should install, or restore an ADOM revision hoping an interface comes back.
Weak answer / trap
“FortiManager is the firewall” or a feature list (FortiGuard, scripts, Fabric). A weak whiteboard is boxes with no Preview and no enforcement point.

Strong framing (say this)

ADOM scopes it. Package holds the policy. Device DB holds the box. Preview proves the delta. The FortiGate enforces. I quote Task Monitor and diagnose dvm device list, not the chassis LED.

Evidence to name

GUI ADOM selector; Policy & Objects → Policy Packages; Device Manager device DB; Install Preview; Task Monitor; diagnose dvm device list pkg:[installed]pkg_prod_in.

Q2 · Compare — policy package vs device database

You add a static route on FGT-IN-01 in Device Manager. A colleague adds a firewall policy in pkg_prod_in. Both click Install. Are those the same database, and what does FortiManager copy first?

Direct answer
Two databases. ADOM database: policy packages, objects, provisioning templates. Device database: complete per-FortiGate config. Install of Policy Package & Device Settings copies related ADOM objects into that device’s DB (VDOM copy), diffs the running FortiGate, then pushes the delta. A route lives in the device DB. A firewall policy lives in the package until that copy.
Why production cares
Restoring an ADOM revision rewinds the package and objects, not the static route. Installing device settings only will not publish the new firewall policy.
Weak answer / trap
“Everything is in the policy package.” Also: treating Retrieve (FGT→device DB) as Install (FMG→FGT).

Strong framing (say this)

Package is the ADOM’s policy. Device DB is the box file. Install merges ADOM objects into that file, then diffs the wire.

Evidence to name

Admin Guide — Sequence of operations for installation (ADOM Database vs Device Database); Install Wizard choice “Policy Package & Device Settings” vs “Device Settings only.”

Q3 · Scenario — Install without preview, second firewall dies

Ticket is “add one policy on FGT-IN-01.” Package pkg_prod_in is assigned to FGT-IN-01 and FGT-IN-02. Junior skips Install Preview and clicks Install. Checkout VIP on FGT-IN-02 disappears. First action — not a reboot, not “disable FortiManager.”

Direct answer
Stop further installs. Open Task Monitor for the install that just ran. Download what Preview would have shown if they had clicked it — Policy Package Diff vs both devices. If an ADOM revision exists, restore it, Preview, Install. If not, fix the package (unassign FGT-IN-02 or revert the object), Preview per device, Install only the intended target. Then re-test checkout on .22.
Why production cares
Installation targets are the blast radius. A shared package is a fleet change even when the ticket named one serial number.
Weak answer / trap
SSH the FortiGate and delete the policy FortiManager will just re-push. Or unmanage the device “so it works.” That splits SoT.

Strong framing (say this)

I will not Install a package until Preview lists only the ticketed devices and lines. Shared assignment is a design choice I name out loud.

Evidence to name

Policy package installation targets; Install Preview download; Policy Package Diff; Task Monitor; ADOM revision ID from the wizard checkbox.

Q4 · Evidence — Modified is not Out of Sync

Device Manager table: FGT-IN-01 policy package status is a yellow triangle, Config Status Synchronized. A junior says the FortiGate changed locally and wants Import Policy. Are they reading the right column?

Direct answer
No. Modified = policies or objects changed on FortiManager, not yet installed. Out of Sync = changed on the managed device. Config Status Synchronized means the device-DB revision matches what FortiManager last confirmed on the box — it does not mean the ADOM package was installed. Next: Preview + Install, not Import.
Why production cares
Importing now copies the old FortiGate policy over the ADOM work you have not installed. You just deleted the change ticket.
Weak answer / trap
“Yellow means down.” “Unknown after a FortiOS upgrade means retrieve and we are healthy” — Unknown after retrieve is documented; you still need a clean install to resync pkg flags.

Strong framing (say this)

I read Policy Package Status and Config Status as two questions: who edited policy, and does the device file match. I name both before I pick Import or Install.

Evidence to name

Device Manager → Device & Groups table (Policy Package Status); Dashboard → Configuration and Installation widget (Config Status: Synchronized / Out_of_sync / Unknown / Auto-update); diagnose dvm device list.

Q5 · Troubleshoot — local FortiGate VIP, Auto-Update lied

Night-shift added a VIP on the FortiGate GUI. FortiManager Config Status shows Auto-Update. Policy package is Out of Sync. Management wants FortiManager to remain source of truth. First check, then the operation that does not keep the VIP.

Direct answer
Auto-Update copied the local change into the device database only. It is not Import. If FMG is SoT: review Install Preview (you will see the VIP disappear if the package never had it), Create ADOM Revision, Install — that overwrites the FortiGate. If the VIP was approved, Retrieve if needed, Import Policy, then Install to clear Out of Sync. Do not disable Auto-Update as step one (config system admin settings / set auto-update disable is a process choice, not an incident fix).
Why production cares
Helpdesk “it is already on FortiManager” after Auto-Update is how a shadow VIP survives the next package install — or how an unapproved VIP gets blessed by a blind Import.
Weak answer / trap
Import immediately “to sync.” That makes the local VIP the ADOM package. Also: Retrieve and stop — package still stale.

Strong framing (say this)

Auto-Update is device DB. Import is the package. Install is the wire. I pick the arrow from who is allowed to win.

Evidence to name

Config Status Auto-update; Policy Package Status Out of Sync; Install Preview lines for config firewall vip; Admin Guide Operations (Install / Import / Retrieve / Auto-Update / Auto-Retrieve).

Q6 · Compare — ADOM revision vs device revision

After a bad object edit you restore yesterday’s ADOM revision. Policy package looks right. FGT-IN-01 still has the wrong static default route and a missing VLAN. Why did restore “not work,” and which store actually holds those lines?

Direct answer
ADOM revision history stores policy packages, objects, and VPN console settings for that ADOM. Restore rewinds those. Interfaces, routing, HA, and other device settings live in the device database / device configuration revision history. You still need Preview + Install after an ADOM restore to put packages back on the FortiGate. Wrong route → Device Manager revision for that device, not Policy & Objects → ADOM Revisions.
Why production cares
Change-control questions are “what can I roll back in five minutes?” If you only snapshot ADOM revisions, you cannot rewind a fat-fingered default route.
Weak answer / trap
“Revision history” as one pile. FortiAnalyzer is a third pile (logs). Rebooting FortiManager does not restore either database.

Strong framing (say this)

ADOM revision = policy/objects/VPN console. Device revision = that box’s file. I create the ADOM revision on the Install Wizard checkbox so the restore exists before I need it.

Evidence to name

Policy & Objects → ADOM Revisions (ID, Name, Restore, CLI Diff vs current database); Install Wizard “Create ADOM Revision”; Device Manager configuration revision history.

Q7 · Unsafe shortcut — shared object without Where Used

Junior changes addr_hq_web from a host to a /24 “so checkout works on FGT-IN-01.” The object is used in pkg_prod_in and in a second package in ADOM PROD-IN. They Install only FGT-IN-01. What still breaks, and what does not leak to PROD-US?

Direct answer
ADOM objects are shared across policy packages in that ADOM. Every package in PROD-IN that references addr_hq_web now has the /24 — including the package you did not open. The next Install to any assigned device publishes it. PROD-US does not see the object unless it lives in the Global Database (or someone cloned it). Fix: Where Used, clone a package-specific object, revert the shared one, Preview, Install.
Why production cares
This is the classic FortiManager outage: the control looks enabled while a second application path is now too wide or too narrow. Old page said it as “object reused across policy packages or ADOM scope without impact review.” That sentence is still the L3 answer.
Weak answer / trap
“I only installed one device so only one device changed” — the ADOM object already changed. Also: putting tenant objects in Global “so we do not duplicate.”

Strong framing (say this)

Where Used first. Clone if the exception is local. I do not edit a shared address to fix one VIP.

Evidence to name

Policy & Objects object Where Used; package assignment list; Global Database vs ADOM objects; Install Preview showing the /24 on the second package’s device.

Q8 · Scenario — “FortiManager is blocking checkout”

Helpdesk: users cannot reach checkout. “FortiManager is blocking us.” A junior wants to disable central management so the FortiGate is standalone. Another wants to restore the last ADOM revision immediately. First framing, then the first evidence.

Direct answer
FortiManager does not forward packets. If checkout dies, the FortiGate policy (or routing, or VIP, or a just-installed package) is on the path. First: last successful Task Monitor install to FGT-IN-01, Preview/Diff of that job, current Policy Package Status. Then FortiGate policy lookup / FortiAnalyzer hit for the client. Unmanaging the device is an SoT split, not a fix. Restore only if Preview of the last install shows the bad delta and a revision exists.
Why production cares
The panel is testing whether you treat FortiManager as a manager plane. Disabling it mid-incident guarantees the next Install is a surprise.
Weak answer / trap
Start by changing the broadest production package, or by Workspace-unlocking everything. Workspace lock does not drop user sessions; it stops a second admin committing over you.

Strong framing (say this)

Manager plane vs data plane. I name the last install, the package, the device, then the FortiGate hit. I do not unmanage a firewall to restore checkout.

Evidence to name

Task Monitor; Install Preview archive; diagnose dvm device list; FortiGate policy hit / FAZ log; Architecture lesson: FGT forwards, FMG writes, FAZ remembers.

8. Traps and proof checklist

TrapWhat you seeSafer next step
Wrong ADOM Package name looks right; device is not in the list GUI ADOM selector → PROD-IN before any edit
Install without Preview Second firewall loses a VIP that was never in the ticket Install Preview + Policy Package Diff + per-device assignment
Modified read as Out of Sync Junior Imports and wipes uncommitted ADOM work Modified → Preview + Install. Out of Sync → decide SoT
Auto-Update treated as Import Device DB has the VIP; package does not Next Install clobbers it, or Import blesses it — pick on purpose
Shared object edit One site’s /24 lands in every package in the ADOM Where Used → clone → revert shared object
ADOM restore for a route Package looks old; VLAN/default route still wrong Device revision history, then Install device settings
No ADOM revision on Install Bad push, nothing to Restore Create ADOM Revision checkbox on the wizard, every time
“FMG is blocking me” Helpdesk wants central management disabled Last install + FortiGate/FAZ hit. FMG does not forward
Two admins, no Workspace Silent object merge, Preview surprises Lock ADOM / package (Workspace) or Workflow approval
Missing normalized interface map Install validation fails after Import Per-device or per-platform mapping before Install
Proof checklist (pilot / interview close)

Knowledge check

Six judgment items. Each maps to a promise bullet. Check answers, then reset and re-read the traps table if you miss any.

Q1

Policy package status on FGT-IN-01 is Modified (yellow). Config Status is Synchronized. What is true?

Correct: c. Modified is uncommitted ADOM work. Re-read Q4 + Flow 2.
Q2

You are in ADOM PROD-IN. Install Wizard is open for pkg_prod_in → FGT-IN-01 and FGT-IN-02. Safest next click?

Correct: b. Preview is the evidence; revision is the rollback. Re-read Q3 + the runbook.
Q3

Night-shift added a VIP on the FortiGate GUI. Config Status is Auto-Update; package is Out of Sync. FortiManager must stay source of truth. What do you do?

Correct: d. Auto-Update is device DB only. FMG-as-SoT means Install, not Import. Re-read Q5.
Q4

addr_hq_web is used in pkg_prod_in and another package in ADOM PROD-IN. A junior edits it to a /24 to fix one site. What is true?

Correct: c. Shared inside the ADOM; isolated across ADOMs unless Global. Re-read Q7.
Q5

You restored an ADOM revision after a bad policy edit. Interfaces and the static default route on FGT-IN-01 are still wrong. Why?

Correct: a. Two stores. Re-read Q6 + the revision table.
Q6

Helpdesk: “FortiManager is blocking checkout.” First framing?

Correct: b. Manager plane vs data plane. Re-read Q8 + Q1.

Sources

Related: FortiManager policy package workflow · FortiGate / FortiManager / FortiAnalyzer · FortiGate policy first match · FortiGate interview · Interview hub