ubuntu hook for channel change

roles/network/tasks/hostapd.yml

@@ -119,7 +119,7 @@
   with_items:
     - { src: 'hostapd/netd-disp', dest: '/etc/networkd-dispatcher/carrier.d/iiab-wifi' }
     - { src: 'hostapd/netd-disp', dest: '/etc/networkd-dispatcher/no-carrier.d/iiab-wifi' }
-    - { src: 'hostapd/netd-disp', dest: '/etc/networkd-dispatcher/routable.d/iiab-wifi' }
+    - { src: 'hostapd/netd-disp2', dest: '/etc/networkd-dispatcher/routable.d/iiab-wifi2' }
   when: systemd_networkd_active and discovered_wireless_iface != "none" and wifi_up_down
 
 - name: Remove networkd-dispatcher hook wifi_up_down False
@@ -130,6 +130,7 @@
     - { dest: '/etc/networkd-dispatcher/carrier.d/iiab-wifi' }
     - { dest: '/etc/networkd-dispatcher/no-carrier.d/iiab-wifi' }
     - { dest: '/etc/networkd-dispatcher/routable.d/iiab-wifi' }
+    - { dest: '/etc/networkd-dispatcher/routable.d/iiab-wifi2' }
   when: systemd_networkd_active and discovered_wireless_iface != "none" and not wifi_up_down
 
 - name: Enable the Access Point 'hostapd' service

roles/network/templates/hostapd/netd-disp

@@ -1,5 +1,4 @@
 #!/bin/bash
-
 if [ "$IFACE" == "{{ discovered_wireless_iface }}" ]; then
     echo "NET-DISP-WiFi $IFACE $STATE"
     /usr/sbin/ip link set ap0 up

roles/network/templates/hostapd/netd-disp2

@@ -0,0 +1,25 @@
+#!/bin/bash
+if [ "$IFACE" == "{{ discovered_wireless_iface }}" ]; then
+    echo "NET-DISP-WiFi $IFACE $STATE"
+    FREQ=`wpa_cli -i $IFACE scan_results | grep $SSID | awk '{print $2}'`
+    for result in $FREQ; do
+        echo "frequency is $result for $SSID"
+        if [ $result -lt 2485 ]; then
+            FREQ2=$result
+        fi
+    done
+    echo "Using $FREQ2 for $SSID"
+    CHAN=$(($FREQ2 - 2407 ))
+    CHAN=$(($CHAN / 5 ))
+    HOSTAPD=`grep channel /etc/hostapd/hostapd.conf | awk -F = '{print $2}'`
+    echo "Hostapd set for $HOSTAPD"
+    if [ $CHAN -ne $HOSTAPD ]; then
+        echo "Editing Hostapd for channel $CHAN"
+        cp /etc/hostapd/hostapd.conf.iiab /etc/hostapd/hostapd.conf
+        sed -i -e "s/^channel.*/channel=$CHAN/" /etc/hostapd/hostapd.conf
+        systemctl stop wpa_supplicant
+        systemctl restart hostapd
+        systemctl start wpa_supplicant
+    fi
+    /usr/sbin/ip link set ap0 up
+fi