AP setup for channel 100 and above

Nagaraj Subas Chandrabose Nagaraj.SubasChandrabose at lumenfreedom.com.au
Thu Aug 12 20:34:13 PDT 2021

Hi All,

I tried to set up a Linux based Variscite DART-6UL board WIFI as an access point using the hostapd.conf file and the hostapd(Ver: 2.9-rc0) application. In the hostapd.conf file, I made the following modifications:
hw_mode=a #(5Ghz)

The above settings worked fine and the DART-6UL board was successfully setup as an AP and broadcasted the given ssid.

The messages logged by the HOSTAPD application are as follows: "showing that the HOSTAPD application is advancing with AP/channel configuration and finally logging the AP-ENABLED message."

hostapd_handle_dfs_offload: freq 5180 MHz does not require DFS. Continue channel/AP setup Proceed with AP/channel setup "
wlan0: interface state COUNTRY_UPDATE->ENABLED
wlan0: Setup of interface done.

However, the hostapd application seems to be not working if I attempt to set the channel to 100 and higher. 

The messages logged by the hostapd application are

DFS support is enabled
Completing interface initialization
Mode: IEEE 802.11a  Channel: 100  Frequency: 5500 MHz
hostapd_handle_dfs_offload: iface->cac_started: 0
hostapd_handle_dfs_offload: freq 5500 MHz requires DFS "
hostapd_setup_interface_complete_sync: Wait for CAC to complete "

Because the DFS-CAC is not yet up and running, the HOSTAPD application is unable to complete the AP/channel setup configuration. The system is unable to start/complete the DFS-CAC functionality despite having the DFS-CAC option enabled in the conf file. As a result, the hostapd programme is always waiting for the system to complete DFS-CAC configuration. Is there a problem with the hospad programme, or do I need to enable any other settings?

Thank you for your support.


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