Ethernet and wifi together

Question

I am trying to connect a web power switch v7 to rpi through the ethernet jack, and then connect the rpi to the internet through usb wifi.

I looked at several QA, including this well voted one: Setting up WiFi and Ethernet

It works, but only if I first start with only the wifi dongle connected, then manually plug in the ethernet cable.

If I start with both plugged in, and reboot, only the ethernet works. The wifi dongle light turns off. My concern is power failures.

What is happening here?

My settings are pretty much lifted from various posts:

/etc/default/ifplugd

INTERFACES="eth0"
HOTPLUG_INTERFACES="eth0"
ARGS="-q -f -u0 -d10 -w -I"
SUSPEND_ACTION="stop"

Start up:

/etc/rc.local
...
sudo ifplugd eth0 --kill
sudo ifup wlan0

Network interfaces:

/etc/network/interfaces
auto lo
iface lo inet loopback

autho eth0
allow-hotplug eth0
iface eth0 inet static
address 192.168.0.51
netmask 255.255.255.0

auto wlan0
allow-hotplug wlan0
# I tried static vs manual, as per the posts, doesn't make a difference
iface wlan0 inet manual
wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf

iface default inet dhcp

And finally my wpa supplicant:

/etc/wpa_supplicant/wpa_supplicant.conf

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

network={
        ssid="[my network name]"
        psk="[my password]"
        proto=RSN
        key_mgmt=WPA-PSK
        pairwise=CCMP TKIP
        group=CCMP TKIP
}

If it matters, running RASPBERRY PI 2 MODEL B, with raspberian UI.

score 4 · Answer 1 · answered Jul 03 '16 at 04:09

I have read through this post, I don't know how many times, but just today I noticed:

autho eth0
allow-hotplug eth0
iface eth0 inet static
address 192.168.0.51
netmask 255.255.255.0

I know this is an old, "fixed" issue, but did you maybe correct the spelling of "autho eth0" along the way, one day? It's good to get things working, but better to know how you did it.

score 2 · Answer 2 · answered May 24 '15 at 18:06

I don't know what happened, but it is working for me.

I was messing around with wifi static ips and all of a sudden it works.

My only change is the following to /etc/network/interfaces

...
auto wlan0
allow-hotplug wlan0
address [desired ip address]
netmask 255.255.255.0
gateway [router ip]
wpa-essid [SSID of wifi]
wpa-psk [wifi pw]
#wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf <--- commented out
....

Maybe my wpa_supplicant.conf was the problem?

This could all be coincidental, but my setup is working.

Perhaps you configured wlan to switch off when eth0 is active. Here is a link I found for this topic: http://www.aoakley.com/articles/2013-07-31-raspberry-pi-networking.php — Peter Paul Kiefer, May 24 '15 at 20:34

score 1 · Answer 3 · edited Oct 02 '17 at 06:44

With the latest version of Jessie, I left everything as standard and added the following to dhcpcd.conf:

interface wlan0
metric 100

interface eth0
metric 300
static ip_address=192.168.1.69/24
static routers=192.168.1.1
static domain_name_servers=192.168.1.1

I can now access the web management interface on a non-DHCP switch connected to eth0. I can, simultaneously, access the Internet from the Pi, or more specific to my use case, use Teamviewer to remote access the Pi from a PC.

If I reboot the Pi, it all works. If I turn WiFi off then back on, it all works. If I unplug the cable to eth0 then plug back in, it all works.

It took me a while to work through the many posts proffering advice, a lot of time and a lot of Pi rebuilds. I hope this helps someone! :O)

score 0 · Answer 4 · edited Aug 09 '16 at 08:31

This post helped me out tremendously... So what I am doing involved hard line connecting my raspy pi and both ethernet and wifi were running. I needed to set the eth0 static and disable the wifi. I got ran... sudo nano /etc/network/interface and added that # mentioned above and poof problem fixed. Looks like this below...

allow-hotplug wlan0
iface wlan0 inte manual
#wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

Ethernet and wifi together

4 Answers4

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