Check fortios-network-io


This plugin checks network I/O and link states on all interfaces found on a Forti Appliance like FortiGate running FortiOS, using the FortiOS REST API. Warns on link up/down, speed or duplex change as well as bandwidth saturation. The authentication is done via a single API token (Token-based authentication), not via Session-based authentication, which is stated as „legacy“.


  • --count=5 (the default) while checking every minute means that the check reports a warning if any interface was above a threshold in the last 5 minutes.

  • Check needs count runs to warm up its caches.

  • The check inventorizes your appliance. If you change any of Forti’s interfaces, and you want to reset the check’s warnings about this, simply delete the $TEMP/linuxfabrik-monitoring-plugins-fortios-network-io.db inventory file.

Fact Sheet

Check Plugin Download

Check Interval Recommendation

Once a minute

Can be called without parameters


Compiled for

Linux, Windows

Handles Periods


Uses SQLite DBs



usage: fortios-network-io [-h] [-V] [--always-ok] [--count COUNT] [-c CRIT]
                          -H HOSTNAME [--insecure] [--no-proxy] --password
                          PASSWORD [--timeout TIMEOUT] [-w WARN]

optional arguments:
  -h, --help            show this help message and exit
  -V, --version         show program's version number and exit
  --always-ok           Always returns OK.
  --count COUNT         Number of times the value has to be above the given
                        thresholds. Default: 5
  -c CRIT, --critical CRIT
                        Set the critical threshold for link saturation for
                        <count> checks, in bps. Default: 900000000
  -H HOSTNAME, --hostname HOSTNAME
                        FortiOS-based Appliance address, optional including
                        port ("").
  --insecure            This option explicitly allows to perform "insecure"
                        SSL connections. Default: False
  --no-proxy            Do not use a proxy. Default: False
  --password PASSWORD   FortiOS REST API Single Access Token.
  --timeout TIMEOUT     Network timeout in seconds. Default: 3 (seconds)
  -w WARN, --warning WARN
                        Set the warning threshold for link saturation for
                        <count> checks, in bps. Default: 800000000

Usage Examples

./fortios-network-io --hostname --password mypass --count 5 --warning 800000000 --critical 900000000


port8: 338.9KiB/33.4KiB bps (rx/tx, current).
interface   ! rx1bps   ! tx1bps  ! rx5bps   ! tx5bps
mgmt1       ! 2.6KiB   ! 2.5KiB  ! 2.6KiB   ! 2.5KiB
modem       ! 0.0B     ! 0.0B    ! 0.0B     ! 0.0B
npu0_vlink0 ! 0.0B     ! 0.0B    ! 0.0B     ! 0.0B
npu1_vlink0 ! 0.0B     ! 0.0B    ! 0.0B     ! 0.0B
npu1_vlink1 ! 0.0B     ! 0.0B    ! 0.0B     ! 0.0B
port8       ! 338.9KiB ! 33.4KiB ! 334.0KiB ! 33.3KiB


  • WARN or CRIT, if network I/O (bps) is greater or equal a given threshold

  • WARN, if link state, speed rate or duplex mode for an interface changes

Perfdata / Metrics

Depends on your hardware. Example:

  • modem_rx1: Received bytes on this interface since the last check

  • modem_tx1: Sent bytes since the last check

  • modem_rxn: Received bytes since the last n checks (default: 5)

  • modem_txn: Sent bytes since the last n checks

Credits, License