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Disk Full / Log Disk Full

Disk Full / Log Disk Full¶

Symptom: Dashboard warns disk is full or near. GUI may degrade. Logs stop saving.

Diagnose¶

# Disk usage:
get system status
diagnose sys logdisk usage

# What's on the log disk:
execute log filter device disk
execute log filter category 0
execute log display

Fixes¶

Trim log retention¶

config log disk setting
    set maximum-log-age 3      # was 7 — drop to 3
    set diskfull overwrite     # overwrite oldest when full
end

Offload to FortiAnalyzer¶

Set up FortiAnalyzer — see Send Logs to FortiAnalyzer. After offloading, drop local log retention to 1 day.

Don't log low-value traffic¶

config firewall policy
edit <id>
    set logtraffic utm    # only security events, not every session
next
end

Clean up reports / snapshots¶

# Old config revisions:
execute config-revision rm <oldest-revision-id>

Manually clear logs (last resort)¶

execute reset logsetting
execute log delete-all

Wipes ALL local logs. Audit/compliance issue if you have retention requirements.

After Fix¶

diagnose sys logdisk usage
# Should show plenty of free space.