{"id":16524,"date":"2017-01-27T10:42:16","date_gmt":"2017-01-27T16:42:16","guid":{"rendered":"http:\/\/www.multitech.net\/developer\/?page_id=16524"},"modified":"2023-01-04T16:22:34","modified_gmt":"2023-01-04T22:22:34","slug":"wifi-access-point","status":"publish","type":"page","link":"https:\/\/www.multitech.net\/developer\/software\/mlinux\/using-mlinux\/wifi-access-point\/","title":{"rendered":"Wi-Fi Access Point"},"content":{"rendered":"

This feature is only available on certain products and models (not available with all devices).<\/p>\n

If you are using Coexistence mode 3<\/strong> (Station + Access Point)<\/strong>, they must both be at the same channel.\u00a0 To determine the channel used by the Wi-Fi Station<\/a>, do the following (from the <\/span>Wi-Fi Station page<\/a>):<\/span><\/span><\/p>\n

mtcdt: iw dev wifi0\u00a0 link\n\nConnected to 9c:4e:20:c8:ee:9e (on wifi0)\nSSID: Mtech_guest\nfreq: 5785<\/pre>\n
The frequency can be used to determine the channel. This channel corresponds to channel 157. This must be used in the Wi-Fi Access Point configuration file.<\/p>\n
Configuring the cfg80211 Driver on the Device<\/span><\/strong><\/p>\n
1. Add the file to the device:<\/p>\n
\/etc\/modprobe.d\/cfg80211.conf<\/pre>\n
The file should contain the country code for the country where the device resides or is used:<\/p>\n
options cfg80211 ieee80211_regdom=US<\/pre>\n
2. After doing this, cfg80211 must be reloaded. Enter the following:<\/p>\n
mtcdt: \/etc\/init.d\/rs9113 stop<\/pre>\n
The following results display:<\/p>\n
rs9113: Unloading rs9113 modules\nkillall: wpa_supplicant: no process killed\nkillall: hostapd: no process killed\nOK<\/pre>\n
Then enter the following commands:<\/p>\n
mtcdt: modprobe -r mac80211\nmtcdt: modprobe -r cfg80211\nmtcdt: lsmod | grep cfg80211\nmtcdt: modprobe cfg80211\nmtcdt: cat \/sys\/module\/cfg80211\/parameters\/ieee80211_regdom\nUS<\/pre>\n
Reloading the Redpine\/RS9113 Driver After a Frequency Change<\/b><\/p>\n
If you change the frequency from 2.4GHz to 5GHz or vice versa, you must reload the rs9113 driver. It is not possible to use 2.4GHz and 5GHz simultaneously.<\/p>\n
For Wi-Fi Access Point, use 2, 3 , 6 or 14 for the COEX_MODE (or coexistence parameter) in \/etc\/default\/rs9113. Always check the COEX_MODE value before loading the driver.<\/p>\n
To reload the driver:<\/p>\n
1. Enter the command:<\/p>\n
mtcdt: \/etc\/init.d\/rs9113 restart<\/pre>\n
2. \u00a0Also, dnsmasq may already be running. The first command looks for the DNS mask. The second command kills the process(es). Include the PID of the process(es). Enter the following two commands:<\/p>\n
mtcdt: ps -ef | grep [d]nsmasq\nmtcdt: kill [pid1] [pid2]<\/pre>\n
Example kill command (one process):<\/p>\n
mtcdt: kill 27565<\/pre>\n
\u00a03. If you have UDHCP running. Enter:<\/p>\n
mtcdt: ps -ef | grep [u]dhcpc\nadmin\u00a0\u00a0\u00a0 27565\u00a0\u00a0\u00a0\u00a0 1\u00a0 0 19:34\u00a0?\u00a0 00:00:00 udhcpc -R -n -p \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\/var\/run\/udhcpc.wifi0.pid -i wifi0<\/pre>\n
Since this is running on wifi0, it is OK. If it is running on wifi1, it should be killed.<\/p>\n
Configuring the Hostapd File<\/b><\/span><\/p>\n
To get an example of the hostapd file, copy one of the following examples listed below:<\/p>\n
1. On the device, find the example hostapd.conf files:<\/p>\n
mtctdt:~ $ cd \/opt\/rs9113\nmtctdt:~ $ ls hostapd* hostapd.conf\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \nhostapd_ccmp.conf\u00a0\u00a0\u00a0 hostapd_eap.conf\u00a0\u00a0\u00a0\u00a0 hostapd_open.conf\u00a0\u00a0\u00a0 hostapd_server.conf\u00a0 hostapd_tkip.conf\u00a0\u00a0\u00a0 hostapd_wep.conf\u00a0\u00a0\u00a0\u00a0 hostapd_wps.conf\npan:\/opt\/rs9113$<\/pre>\n
2. Start with the file,\u00a0 hostapd_open.conf. So the device can use the hostapd daemon on boot, rename the\u00a0example file and copy it to this new location:<\/p>\n
\/var\/config\/hostapd.conf<\/pre>\n
The simplest example of the hostapd file is \/opt\/rs9113\/hostapd_open.conf. In this case, we are using wifi1 as the device.<\/p>\n
\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 hostapd*.conf will have commentary in the file explaining the various parameters.<\/p>\n
You can also find an example online of a hostapd file from the hostapd project:<\/p>\n
https:\/\/w1.fi\/cgit\/hostap\/plain\/hostapd\/hostapd.conf<\/a><\/p>\n
In the following sequence, a minus<\/i> means remove, next to a line of the original \/opt\/rs9113\/hostapd_open.conf<\/strong>. A plus<\/i> means add, next to the replacement line in the new file,\u00a0\/var\/config\/hostapd.conf<\/strong>.<\/p>\n
3. Open your example file and find the interface line. Set it to wifi1:<\/p>\n
-interface=wifi0\nCHANGE TO:\n+interface=wifi1<\/pre>\n
4. Find the file’s hw_mode and set it to the desired frequency band (g<\/b> is 2.4GHz<\/b> and a<\/b> is 5GHz<\/b>). The original file is set to g<\/b> or 2.4GHz<\/b>. Once this is set by the hostapd daemon, you cannot change the frequency without reloading the driver.<\/p>\n
Here are the parameters for each mode:<\/p>\n
-hw_mode=g\nOR\n+hw_mode=a<\/pre>\n
5. Set the file’s channel number. The channel number is restricted by country or region. Here are some example parameters for setting the channel number:<\/p>\n
-channel=1\nOR\n+channel=36<\/pre>\n
The channel number must be consistent with the hardware mode. Channels 1 – 14 are 2.4GHz<\/b> or hardware mode g<\/b>, and channels above 14 are 5GHz<\/b> or mode a<\/b>.<\/p>\n
Adding the Wi-Fi Access Point Driver Node on the Device<\/b><\/span><\/p>\n
Add the Wi-Fi Acccess Point driver node on the device. This strarts the wifi driver on \/dev\/wifi1:<\/p>\n
1. To intialize the driver and create the Virtual Access Point (VAP), enter the following command (note: the name of the driver is wifi1):<\/p>\n
mtcdt: \/opt\/rs9113\/onebox_util rpine0 create_vap wifi1 ap\nDriver initialization is done\nCreating VAP in AP mode\nVAP created Successfully<\/pre>\n
2. Now activate the access point, start the daemon and give it an IP address using these commands:\u00a0<\/span><\/p>\n
mtcdt: hostapd -B -d  \/var\/config\/hostapd.conf\nmtcdt: ip -4 addr flush dev wifi1\nmtcdt: ip addr add 10.0.0.1\/8 dev wifi1\nmtcdt: ip addr show wifi1<\/pre>\n
The following results display:\u00a0<\/span><\/p>\n
11: wifi1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000\n\u00a0 \u00a0 \u00a0link\/ether 00:23:a7:43:9e:e9 brd ff:ff:ff:ff:ff:ff\n\u00a0 \u00a0 \u00a0inet 10.0.0.1\/8 scope global wifi1\n\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0valid_lft forever preferred_lft forever\n\u00a0 \u00a0 \u00a0inet6 fe80::223:a7ff:fe43:9ee9\/64 scope link\n  \u00a0 \u00a0 \u00a0 \u00a0 \u00a0valid_lft forever preferred_lft forev<\/pre>\n
If hostapd produces errors, the COEX_MODE is incorrect.<\/p>\n
Running dnsmasq<\/b><\/span><\/p>\n
1. Kill off any existing DHCP or DNS server.<\/p>\n
2. Edit the file \/etc\/default\/dnsmasq<\/strong> making Enabled=”yes”, if it’s not already set this way.<\/p>\n
3. Stop dnsmasq<\/b>\u00a0using the command:\u00a0<\/span><\/p>\n
mtcdt: \/etc\/init.d\/dnsmasq stop<\/pre>\n
4. Place the configuration file in \/etc\/dnsmasq.d\/dhcp.conf\u00a0<\/strong>on the device.\u00a0<\/span><\/p>\n
interface=wifi1\ndhcp-range=10.0.0.100,10.0.0.250,12h\ndhcp-lease-max=200\ndhcp-leasefile=\/var\/config\/dnsmasq_dhcp_wifi1.leases\ndhcp-option=option:netmask,255.255.255.0\ndhcp-option=option:router,10.0.0.1\ndhcp-option=option:dns-server,10.0.0.1\ndhcp-authoritative<\/pre>\n
5. Copy this DNS file with contents below into \/etc\/dnsmasq.d\/dns.conf<\/strong>.<\/p>\n
no-hosts\naddn-hosts=\/var\/config\/hosts<\/pre>\n
6. Start the daemon:\u00a0<\/span><\/p>\n
mtcdt: \/etc\/init.d\/dnsmasq start\nmtcdt: ps -ef | grep [d]nsmasq\nnobody\u00a0\u00a0 1632\u00a0\u00a0\u00a0\u00a0 1\u00a0 0 18:41\u00a0?\u00a0    00:00:00 \/usr\/bin\/dnsmasq -7 \/etc\/dnsmasq.d<\/code><\/pre>\n
Enabling Wi-Fi Routing<\/b><\/span><\/p>\n
Before doing these steps, you must setup the Ethernet connection on the device and configure the COEX_MODE = 3 (Wi-Fi Station and Wi-Fi Access Point).<\/p>\n
To enable Wi-Fi Routing:<\/p>\n
1. For the access point to work (access the device from your computer), you need to lower the firewall settings to allow access. Enter the following commands:<\/p>\n
mtcdt: iptables -P INPUT ACCEPT\nmtcdt: iptables -P FORWARD ACCEPT\nmtcdt: iptables -P OUTPUT ACCEPT\nmtcdt: iptables -t nat -F\nmtcdt: iptables -t mangle -F\nmtcdt: iptables -F\nmtcdt: iptables -X\nmtcdt: iptables -L<\/pre>\n
Chain INPUT (policy ACCEPT)<\n target\u00a0\u00a0\u00a0\u00a0 prot opt source\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 destination\nChain FORWARD (policy ACCEPT)\n target\u00a0\u00a0\u00a0\u00a0 prot opt source\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 destination\nChain OUTPUT (policy ACCEPT)\n target\u00a0\u00a0\u00a0\u00a0 prot opt source\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 destination<\/pre>\n
2. Connect Wi-Fi through your PC running Linux . Then, verify the device Wi-Fi connection to your computer. Enter this command:\u00a0<\/span><\/p>\n
pc: ip addr show wlan0<\/pre>\n
The following results should display:\u00a0<\/span><\/p>\n
4: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000\nlink\/ether b0:7f:b9:f8:3f:b3 brd ff:ff:ff:ff:ff:ff\ninet 10.0.0.182\/24 brd 10.0.0.255 scope global wlan0\n\u00a0 \u00a0 \u00a0valid_lft forever preferred_lft forever\ninet6 fe80::b27f:b9ff:fef8:3fb3\/64 scope link\n\u00a0 \u00a0 \u00a0valid_lft forever preferred_lft forever<\/pre>\n
3. In order to access the internet through the device from your computer, you must enable minimal forwarding of DHCP.\u00a0 NOTE:<\/b> this step forwards DHCP and does not work with DHCP set up prior to this step. Do the forwarding step after the IP address is acquired via DHCP.<\/p>\n
\u00a0a.\u00a0Enable IP forwarding using this command:<\/p>\n
mtcdt: echo 1 > \/proc\/sys\/net\/ipv4\/ip_forward<\/pre>\n
b. Then change the ip tables to forward from wifi1 (the wifi access point) to wifi0 (the Wi-Fi station VAP).<\/p>\n
mtcdt: iptables -t nat -A POSTROUTING -o wifi0 -j MASQUERADE\nmtcdt: iptables -A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT\nmtcdt: iptables\u00a0 -A FORWARD -i wifi1 -o wifi0 -j ACCEPT\nmtcdt: iptables -L<\/pre>\n
Chain INPUT (policy ACCEPT)\ntarget\u00a0\u00a0\u00a0\u00a0 prot opt source\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 destination\nChain FORWARD (policy ACCEPT)\ntarget\u00a0\u00a0\u00a0\u00a0 prot opt source\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 destination\nACCEPT\u00a0\u00a0\u00a0\u00a0 all\u00a0 --\u00a0 anywhere\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 anywhere\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 ctstate RELATED,ESTABLISHED\nACCEPT\u00a0\u00a0\u00a0\u00a0 all\u00a0 --\u00a0 anywhere\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 anywhere\nChain OUTPUT (policy ACCEPT)\ntarget\u00a0\u00a0\u00a0\u00a0 prot opt source\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 destination<\/pre>\n
Setting Up Wi-Fi Access Point at Boot<\/span><\/h3>\n
1. First add the IP address of the station to the \/etc\/network\/interfaces<\/strong> file:<\/p>\n
auto wifi1\niface wifi1 inet static\naddress 10.0.0.1\nnetmask 255.0.0.0<\/pre>\n
2. Delete and copy the dnsmasq configuration files to the directory \/etc\/dnsmasq.d<\/strong>\u00a0<\/span><\/p>\n
mtcdt: rm \/etc\/dnsmasq.d\/*\nmtcdt: cp dnsmasq_dhcp.conf dnsmasq_dns.conf \/etc\/dnsmasq.d<\/pre>\n
3. Now restart the interface, and restart dnsmasq<\/strong> using the following commands:\u00a0<\/span><\/p>\n
mtcdt: ifup wifi1\nmtcdt: ifdown wifi1\nmtcdt: ifup wifi1<\/pre>\n
The resulting output displays:\u00a0<\/span><\/p>\n
10: wifi1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000\n    link\/ether 00:23:a7:43:4e:b1 brd ff:ff:ff:ff:ff:ff\n    inet 10.0.0.1\/8 brd 10.255.255.255 scope global wifi1\n       valid_lft forever preferred_lft forever\n    inet6 fe80::223:a7ff:fe43:4eb1\/64 scope link \n       valid_lft forever preferred_lft forever<\/pre>\n
4.\u00a0 Modify configuration for \/etc\/default\/hostapd file:<\/p>\n
#Set to \"yes\" to start hostapd on boot (default is no, change to yes)\nSTART_ON_BOOT=\"yes\"\n#Lines to create the device if needed. \nDEV=wifi1 \nPREUP=\"[[ -d \/sys\/class\/net\/${DEV} ]] || \/opt\/rs9113\/onebox_util rpine0 create_vap ${DEV} ap\" \nPOSTUP=\"ifup wifi1\"<\/pre>\n
5. Modify configuration for\u00a0\/etc\/default\/dnsmasq file:<\/p>\n
# See \/etc\/init.d\/dnsmasq (default is no, change to yes)\nENABLED=\"yes\" \n# Ignore the resolve.conf from the resolvconf package. \nIGNORE_RESOLVCONF=\"yes\"<\/pre>\n
6. Start dnsmasq DHCP using command:<\/p>\n
mtcdt: \/etc\/init.d\/dnsmasq restart<\/pre>\n
To confirm it has started:<\/p>\n
mtcdt:ps -ef | grep [d]nsmasq<\/pre>\n
7. Start hostapd<\/b> using command:<\/p>\n
mtcdt:\u00a0\/etc\/init.d\/hostapd\u00a0restart<\/pre>\n
To confirm it has started:<\/p>\n
mtcdt:ps -ef | grep [h]ostapd<\/pre>\n","protected":false},"excerpt":{"rendered":"
This feature is only available on certain products and models (not available with all devices). If you are using Coexistence mode 3 (Station + Access Point), they must both be at the same channel.\u00a0 To determine the channel used by the Wi-Fi Station, do the following (from the Wi-Fi Station page): mtcdt: iw dev wifi0\u00a0 […]<\/p>\n","protected":false},"author":1478,"featured_media":0,"parent":9184,"menu_order":11,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"footnotes":""},"class_list":["post-16524","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.multitech.net\/developer\/wp-json\/wp\/v2\/pages\/16524","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.multitech.net\/developer\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.multitech.net\/developer\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.multitech.net\/developer\/wp-json\/wp\/v2\/users\/1478"}],"replies":[{"embeddable":true,"href":"https:\/\/www.multitech.net\/developer\/wp-json\/wp\/v2\/comments?post=16524"}],"version-history":[{"count":86,"href":"https:\/\/www.multitech.net\/developer\/wp-json\/wp\/v2\/pages\/16524\/revisions"}],"predecessor-version":[{"id":33265,"href":"https:\/\/www.multitech.net\/developer\/wp-json\/wp\/v2\/pages\/16524\/revisions\/33265"}],"up":[{"embeddable":true,"href":"https:\/\/www.multitech.net\/developer\/wp-json\/wp\/v2\/pages\/9184"}],"wp:attachment":[{"href":"https:\/\/www.multitech.net\/developer\/wp-json\/wp\/v2\/media?parent=16524"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}