Configure an AP’s Radios with the CLI
Before you can configure any radio settings, you need to enter radio interface configuration mode. To do this, follow these steps:
TABLE 22: Entering Radio Interface Configuration Mode
| Command | Purpose |
| configure terminal | Enter global configuration mode. |
| interface Dot11Radio <ap-id> <Interface ID> | Enter interface configuration for the specified AP and radio interface. Use show interfaces Dot11Radio to obtain a list of radio interfaces.
For AP800, the second interface provides 802.11ac support. |
| … commands … | Enter the 802.11 configuration commands here. |
| end | Return to privileged EXEC mode. |
| copy running-config startup-config | This is an optional step to save your entries in the configuration file. |
Summary of Radio Interface Configuration Commands
The following is a summary of the commands available in radio interface configuration mode: TABLE 23: Commands available in Radio Interface Configuration Mode
| Command | Purpose |
| admin-mode | Enables or disables a radio interface. |
| antenna-property | Manages external wireless interface antennas. |
| channel | Configures the channel ID. |
| localpower | Configures the AP transmit power level for all APs |
| mode | AP mode configuration. |
| n-only-mode | Supports only 802.11n clients on the radio to improve performance. |
| preamble-short | Enables or disables short preambles. |
| protection-mode | Configures 802.11b/g interoperability mode. This setting defaults to auto and should not be changed without consulting Fortinet Support. |
Configure an AP’s Radios with the CLI
TABLE 23: Commands available in Radio Interface Configuration Mode
| Command | Purpose |
| rf-mode | Configures the Radio Frequency mode (802.11a, b, g, or bg, bgn, or an). Note that All APs on the same channel in a Virtual Cell must have the same setting for rf-mode. |
| scanning channels | Configures the channels for scanning |
| tuning | Tunes the wireless interface |
Set Radio Transmit Power with the CLI
The radio transmit power changes the AP’s coverage area; this setting helps manage contention between neighboring access points. Transmit power for Fortinet APs is defined as the EIRP1 (Effective Isotropic Radiated Power) at the antenna and includes the antenna gain.
(This is important to remember; transmit power is not the power at the connector.) Power level settings are dependent on the country code and the radio band (and for 802.11a, the channel) in use.
For example, if the transmit power, configured with the command localpower, is set to 20 dBm2, and the antenna gain is set 3 to 2 dBm, then the actual transmitted power at the connector is 18 dBm.
If an external antenna with an 8dBi (isotropic) gain is used, then adjust the gain value to the same value, 8. If the desired EIRP after the antenna is the same, then keep the transmit power set to the same value, 20. For higher or lower EIRP values, adjust the transmit power to the desired value.
The maximum power setting is an integer between 4-30dBm for 802.11/bg radios.
The Maximum Transmit Power for the 802.11a band is based on the channel in use, as detailed in the following table, which shows the levels for the United States:
| 802.11a Channel | Maximum Transmit Power (dBm) for United States |
| 36 | 17 |
| 40 | 23 |
| 44 | 23 |
| 48 | 23 |
| 52 | 30 |
| 56 | 30 |
| 60 | 30 |
| 64 | 30 |
| 100 | 30 |
| 104 | 30 |
Configure an AP’s Radios with the CLI
| 802.11a Channel | Maximum Transmit Power (dBm) for United States |
| 108 | 30 |
| 112 | 30 |
| 116 | 30 |
| 120 | 30 |
| 124 | 30 |
| 128 | 30 |
| 132 | 30 |
| 136 | 30 |
| 140 | 30 |
| 149 | 36 |
| 153 | 36 |
| 157 | 36 |
| 161 | 36 |
| 165 | 36 |
Use the localpower command in the Dot11Radio interface configuration mode to configure the maximum power level. localpower max‐level
For example, to set the 802.11a radio maximum power to 15, type
localpower 15
Enable and Disable Short Preambles with the CLI
The radio preamble, also called the header, is a section of data at the head of a packet that contains information that the access point and client devices need when sending and receiving packets. By default, a short preamble is configured, but you can set the radio preamble to long or short:
- A short preamble improves throughput performance.
- A long preamble ensures compatibility between the access point and some older wireless LAN cards. If you do not have any older wireless LAN cards, you should use short preambles.
To disable short preambles and use long preambles, type: no preamble-short
To enable short preambles, type: preamble-short
Configure an AP’s Radios with the CLI
Set a Radio to Scan for Rogue APs with the CLI
To configure radios to constantly scan for rogue APs, use this command from the Dot11Radio interface configuration mode: mode scanning
To set the radio back to servicing clients, use the command: mode normal
Enable or Disable a Radio Interface with the CLI
To temporarily disable a radio interface, use this command from Dot11Radio interface configuration mode: admin‐mode Down
To later enable the off-line interface, use the command: admin‐mode Up
Set a Radio to Support 802.11n Only with the CLI
To set an AP radio interface to support only 802.11n clients, and thus improve throughput, from the Dot11Radio interface configuration mode use the command: n‐only‐mode
To disable the 802.11n-only support, use the command: no n‐only‐mode
Note that All APs on the same channel in a Virtual Cell must have the same setting for n-only mode.