FortiManager Policy Package Installation Failure: Verification Syntax Conflict
During policy package installation from FortiManager to multi-VDOM FortiGate clusters, obsolete CLI attributes in compiled scripts trigger Phase 2 syntax verification errors, aborting the transactional commit and causing auto-rollback.
Technical Root Cause Analysis
When FortiManager pushes a policy package to a FortiGate, it compiles policy objects, address tables, and interface definitions from the Administrative Domain (ADOM) database into a staged batch CLI configuration script. This execution operates in a strict two-phase commit: Phase 1 copies and stages the script across the FGFM tunnel; Phase 2 tests syntax verification against the FortiGate's local CMDB parser.
Due to schema version divergence between FortiManager ADOM definitions and target FortiOS minor builds, obsolete CLI attributes (such as set match-vip enable in proxy inspection policies, deprecated tcp-mss-sender directives, or renamed SSL profile options) remain in the generated copy script. When the FortiGate CLI parser executes verification, it flags an invalid command error (command parse error before '...'). Because FortiOS mandates strict atomic commits during central management pushes, any verification syntax error halts the transaction, triggering an immediate auto-rollback to the pre-install snapshot and leaving FortiManager in a persistent "Config Out-of-Sync" state.
Affected Firmware & Blast Radius Matrix
| FortiOS Branch | Vulnerable Builds | Confirmed Clean Build | Status & Workaround |
|---|---|---|---|
| FortiOS 7.2 | 7.2.4 – 7.2.7 | 7.2.8+ | Scrub deprecated policy attributes in ADOM |
| FortiOS 7.4 | 7.4.0 – 7.4.2 | 7.4.3+ | Align ADOM schema version in FortiManager |
| FortiOS 7.0 | 7.0.12 – 7.0.14 | 7.0.15+ | Re-import device policy settings to FMG |
Platform Impact: Predominantly impacts multi-VDOM FortiGate 100F to 1000F enterprise clusters managed by FortiManager 7.0, 7.2, and 7.4 during bulk policy rollout windows.
Step 01: Free Verification CLI (Safe Read-Only)
Execute these diagnostic commands on the target FortiGate to isolate the exact rejected CLI line, verify configuration checksums, and extract transaction error records:
Diagnostic Commands
# 1. Read FortiOS CLI configuration error log to capture rejected syntax
diagnose debug config-error-log read
# 2. Check global and per-VDOM configuration checksums
diagnose sys checkum fgt
# 3. Inspect specific VDOM configuration checksum divergence against FortiManager
diagnose sys checkum cfg-system root
# 4. Dump recent FGFM installation transaction error history
diagnose test application fgfmd 9Remediation & Workaround Steps (Teaser Preview)
Review the automated step-by-step remediation procedures available inside the Ferrite interactive platform:
Frequently Asked Questions
The FortiManager policy compiler incorporates obsolete CLI attributes into the copy script. During Phase 2 validation, the FortiGate CLI parser rejects the command, aborting the installation and reverting candidate changes.
No. The automatic rollback safely reverts to the pre-install snapshot without interrupting active user traffic or tearing down established firewall sessions.
FortiManager 7.2.8 and 7.4.3+ introduce updated ADOM parser rules and automatic syntax deprecation filters.