Ubuntu 12.04 - no internet after wakeup, wifi/lan connected, but reaching only local network

Question

I have a strange problem on Toshiba Satellite NB and Ubuntu 12.04 on it. This system is working flawlessly a couple of months now already, but since last week I am getting a strange problem.

I put my NB to sleep/hibernate > Wake up > Wifi/LAN connects to network again > IP is assigned > no internet. After wakeup I can ping only local IPs like the gateway IP 192.168.1.1 or other PCs in my local network, but I can't ping servers like 8.8.8.8 or other public IPs. The only solution is to reboot the system. Afterwards internet works. With the same IP assigned.

One week ago it worked, I am sure. I suspect some latest updates which I did install on wednesday 16.7. I didn't do any dramatic software changes in the recent days. How can I list all the recent updates I have installed? Can I roll back to test the "last working state"?

As for the investigation I have done a bit x-testing with following results:

1. disabled networking before putting to sleep and enabling after wakeup > same thing
2. connecting to either a WiFi or LAN cable > same on both
3. just disabling networking without sleep > enabling networking > same thing
4. sudo service networking restart > same as No. 3
5. made custom script in /etc/pm/sleep.d/ with different commands to stop networking on sleep|hibernate and start upon wakeup > same as 3.
6. sudo modprobe -r iwlwifi > then modprobe iwlwifi > same
7. boot into windows 7 on 2nd partition > connect to wifi > sleep > wake > internet works
8. compared ifconfig before and after sleep > same

It is ridiculous, that local lan works. If a networking kernel module would be "dead" i wouldn't ping anything, or I wouldn't connect to a network at all, or not? On Windows I would try to do something like

ipconfig -release / -renew / -flushdns

Is there any similar function in Ubuntu ?

There is definitely something to restart to get it working, because a complete system restart helps, but I wasn't able to identify what. Maybe somebody could help?

I fount another thread on askubuntu with exact the same questions, but nobody answered.. What's weird, it's a Satellite there as well. https://askubuntu.com/questions/454370/12-04-wireless-is-connected-but-is-not-functional-after-suspend

Answer 1

I should feel bad..

After digging into another similar threads I found an advise to try traceroute. This is where I found my problem. After a fresh reboot i did traceroute google.com and I clearly recognized the first IP after my GW as that of my home's ISP (i am abroad now) and I quickly found out, that I am "auto"connected to my VPN, which I have set up a week ago. whatsmyip.org proved it.

As for the fact, that OpenVPN autoconnects every entry found in /etc/openvpn/xyz.conf I was very supprised, because I have configured it via network-manager and the checkbox "Autoconnect" there is UN-CHECKED! But /etc/default/openvpn says different.

# Start only these VPNs automatically via init script.
# Allowed values are "all", "none" or space separated list of
# names of the VPNs. If empty, "all" is assumed.
# The VPN name refers to the VPN configutation file name.
# i.e. "home" would be /etc/openvpn/home.conf
#
#AUTOSTART="all"
#AUTOSTART="none"
#AUTOSTART="home office"

..argh.. There is definitely a possible point of confusion for other Ubuntu users in this config file vs. network-manager setting.

OK. SOLUTION.

uncomment

AUTOSTART="none"

and reboot

I assume that when a system is connected to vpn and put to sleep/hibernate it won't disconnect correctly and reconnect after resume. Instead the connection turns into an dead end. That is what caused "no internet" probably. Now SUSPEND and RESUME > internet works!

Answer 2

You can try with this

sudo systemctl restart network-manager.service

If works, you can add the script in

/etc/systemd/system/wifi-resume.service

as

#/etc/systemd/system/wifi-resume.service
#sudo systemctl enable wifi-resume.service
[Unit]
Description=Restart networkmanager at resume
After=suspend.target
After=hibernate.target
After=hybrid-sleep.target

[Service]
Type=oneshot
ExecStart=/bin/systemctl restart network-manager.service

[Install]
WantedBy=suspend.target
WantedBy=hibernate.target
WantedBy=hybrid-sleep.target

This works for me after update update ubuntu 16.04 LTS on March 17