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Wireless networking not working after resume in Ubuntu 14.04

[Update]:
The same problem exists in Kubuntu and is solved in the same manner.
[Solved]:
By applying the following command nmcli nm I got the following:

Before suspend

RUNNING         STATE           WIFI-HARDWARE   WIFI       WWAN-HARDWARE   WWAN      
running         connected       enabled         enabled    enabled         enabled  

as can you see the state is connected and the rest are enabled and running

After suspend

RUNNING         STATE           WIFI-HARDWARE   WIFI       WWAN-HARDWARE   WWAN      
running         asleep          enabled         enabled    enabled         disabled

as can you see the state is asleep meaning our dear network manager is still napping, so to solve use the fallowing command line:
sudo nmcli nm sleep false
this tells the network manager to wake the hell up. to make this permenant :
create a script in /etc/pm/sleep.d containg the following (and don't forget to mark the script as executable):

#!/bin/sh

case "${1}" in
        resume|thaw)
        nmcli nm sleep false
                ;;
esac

Thanks to this

The original problem:

I just downloaded Ubuntu 14.04 and installed on my laptop: ASUS X61SL with Intel P8400 Core2Duo x64 processor.
When I close the lid, the system is suspended, but when I open the lid again and resume, the wireless networking is not activited (networking as a whole is disabled), and when I select "Enable Networking" nothing happens.
This is the information about my wireless adapter:

$ lspci | grep -i wireless
02:00.0 Network controller: Qualcomm Atheros AR928X Wireless Network Adapter (PCI-Express) (rev 01)  

This problem wasn't present in Ubuntu 13.04, Linux Mint Debian Edition or Debian 7 wheezy (GNOME or KDE).

Edit: few test with the following results :
The problem effects my wireless and wired networking.
Note: I need to add the pci=nomsi line to grub in order to boot.
When logging out manually then suspend then resume then log in every thing works just fine.
When suspending directly while logged in the problem happens.
Locking and suspending causes the same problem as suspending directly.
Also this problem appearnlty affects log out function: if you chose log out from the user menu in unity panel then you wan't log out, but if you use the command line gnome-session-quit --logout then you can log out.
Now with lshw -C network output:
Normal (fully functional networking):

  *-network               
       description: Ethernet interface
       product: 191 Gigabit Ethernet Adapter
       vendor: Silicon Integrated Systems [SiS]
       physical id: 4
       bus info: pci@0000:00:04.0
       logical name: eth0
       version: 02
       serial: 00:24:8c:1e:f8:53
       size: 10Mbit/s
       capacity: 100Mbit/s
       width: 32 bits
       clock: 33MHz
       capabilities: pm bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=sis190 driverversion=1.4 duplex=half latency=0 link=no multicast=yes port=MII speed=10Mbit/s
       resources: irq:19 memory:fddfcc00-fddfcc7f ioport:cc00(size=128)
  *-network
       description: Wireless interface
       product: AR928X Wireless Network Adapter (PCI-Express)
       vendor: Qualcomm Atheros
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: wlan0
       version: 01
       serial: 00:15:af:e2:13:db
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=ath9k driverversion=3.13.0-24-generic firmware=N/A ip=6.6.6.8 latency=0 link=yes multicast=yes wireless=IEEE 802.11bgn
       resources: irq:16 memory:fdff0000-fdffffff

After resume ("/etc/pm/config.d" does not contains "unload_modules"):

 *-network DISABLED      
       description: Ethernet interface
       product: 191 Gigabit Ethernet Adapter
       vendor: Silicon Integrated Systems [SiS]
       physical id: 4
       bus info: pci@0000:00:04.0
       logical name: eth0
       version: 02
       serial: 00:24:8c:1e:f8:53
       size: 10Mbit/s
       capacity: 100Mbit/s
       width: 32 bits
       clock: 33MHz
       capabilities: pm bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=sis190 driverversion=1.4 duplex=half latency=0 link=no multicast=yes port=MII speed=10Mbit/s
       resources: irq:19 memory:fddfcc00-fddfcc7f ioport:cc00(size=128)
  *-network DISABLED
       description: Wireless interface
       product: AR928X Wireless Network Adapter (PCI-Express)
       vendor: Qualcomm Atheros
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: wlan0
       version: 01
       serial: 00:15:af:e2:13:db
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=ath9k driverversion=3.13.0-24-generic firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11bgn
       resources: irq:16 memory:fdff0000-fdffffff

When I added the file unload_modules to directory "/etc/pm/config.d" as suggested by here, after logging out, suspend ,resume then log in the networking works but I cannot connect to my wireless network.
Again the result of lshw -C network After resume ( "/etc/pm/config.d" contains "unload_modules"):

 *-network DISABLED      
       description: Ethernet interface
       product: 191 Gigabit Ethernet Adapter
       vendor: Silicon Integrated Systems [SiS]
       physical id: 4
       bus info: pci@0000:00:04.0
       logical name: eth0
       version: 02
       serial: 00:24:8c:1e:f8:53
       size: 10Mbit/s
       capacity: 100Mbit/s
       width: 32 bits
       clock: 33MHz
       capabilities: pm bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=sis190 driverversion=1.4 duplex=half latency=0 link=no multicast=yes port=MII speed=10Mbit/s
       resources: irq:19 memory:fddfcc00-fddfcc7f ioport:cc00(size=128)
  *-network DISABLED
       description: Wireless interface
       product: AR928X Wireless Network Adapter (PCI-Express)
       vendor: Qualcomm Atheros
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: wlan0
       version: 01
       serial: 00:15:af:e2:13:db
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=ath9k driverversion=3.13.0-24-generic firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11bgn
       resources: irq:16 memory:fdff0000-fdffffff

The contents of 'unload_modules" where:

SUSPEND_MODULES="$SUSPEND_MODULES ath9k"
SUSPEND_MODULES="$SUSPEND_MODULES sis190"

Where 'ath9k' is my wireless module and 'sis190' is my Ethernet module.


Source: (StackOverflow)

How to connect and disconnect to a network manually in terminal?

Since the network manager is troubling me so much I want to replace it (possibly wicd orNM from ppa:volanin).

I do not know how to connect and disconnect to the network through the terminal without using network manager.

I would like a command-line way of managing the network.


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When I clicked on additional drivers on Ubuntu 12.04, I could not see any drivers.. How can I check what drivers are installed for WiFi on Ubuntu environment.


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Can someone please help me with a complete step by step guide to share my internet connection (which is through a USB modem by ZTE) with my iphone 3G?


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Every time I restore my computer from sleep or turn it on a window pops up asking for my wireless password. Once I enter it it connects successfully, but this happens every time. I'm using Ubuntu 11.10 with all updates installed. Shouldn't the password be remembered so you don't have to enter it every time I get on?

Anyone know why this is happening and how to fix it?


Source: (StackOverflow)

Create WiFi hotspot on ubuntu

Although many questions have already been asked regarding WiFi hotspot, I didn't get any of the solutions working for me.

I connect to the Internet using a 3G Dongle of Huawei 3772 (Vodafone). The connection type is Mobile Broadband connection. I have to share this Internet connection with my other devices like mobile phones and laptops.

How can I create a WiFi hotspot connection for this connection.

I am using Ubuntu 12.04 LTS.

I would like to note that I have already tried some help links from Ubuntu but, they are so confusing that I could not understand them.


Source: (StackOverflow)

How do I connect to a WPA wifi network using the command line?

So basically, I'd like to use iwconfig to connect to my wifi network when I'm not inside X. But I just don't see a way to do it in the man page. Any idea?


Source: (StackOverflow)

Network service discovery disabled: What does this mean for me?

Every time at boot I get a message “Network service discovery disabled. Your current network has a .local domain, which is not recommended and incompatible with the Avahi network service discovery. The service has been disabled.”

Network service discovery disabled

What does this mean for me?

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Source: (StackOverflow)

How to share a wired Internet connection with an Android phone (reverse-tethering)?

I have been trying to share my wired Internet connection with my Android phone. However I could not succeed in doing this. Has anyone of you ever succeeded? Operating systems that I use are as follows:

  • Ubuntu 10.10
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Source: (StackOverflow)

How to set up Ubuntu as wireless accesspoint?

How can I set up my WiFi to be used as wireless access point on Ubuntu Server?

I have a local Ubuntu Server, it has a wireless card in it (802.11a/b/g/n) and I really want to set it up as an 802.11n access point since my normal access point does not support N.

It needs to work as a switch as well so I can connect and get DHPC through.

Edit: I don't see Network Manager as a good solution since it depends on a lot of X11 packages, and i don't want that on a server.


Source: (StackOverflow)

"Starting Wireless Hotspot..." but nothing happens

I was trying to create an WiFi hotspot for my android device. I used ap-hotspot to do so.

I configured the ap-hotspot using

sudo ap-hotspot configure

Then I started ap-hotspot using

sudo ap-hotspot start

Then it shows this

Starting Wireless Hotspot...

And then nothing happens, no further message is displayed, hotspot is not created.

What is Wrong? How to fix it?


Source: (StackOverflow)

A tool to measure signal strength of wireless

I want to know if there exists any command line option or GUI tool (Ubuntu 11.10) so that I can measure the strength of wireless signal at a given location. I have a house where the wireless is not easily accessible at all corners I want to know at which corners or rooms the signal is weak.


Source: (StackOverflow)

How can I adjust the preferred WiFi order? [duplicate]

This question already has an answer here:

I am using 13.04 Ubuntu. I want to make order on multiple wireless access.

Is there any way to do this?


Source: (StackOverflow)

My WiFi adapter is not working at all, how to troubleshoot?

On this site I see hundreds if not a thousand questions being asked about issues with a Wireless LAN adapter not being detected/recognized by Ubuntu. Some mainstream adapters appear to be utterly broken in Linux support, while others just require some simple steps to get it to work.

The options to get it to work appear to be infinitely huge and I have no clue where to get started!

What is considered 'best practice'? What order of things to try is most efficient in terms of time, effort and imposes minimal risk to my Ubuntu installation? Please help me save time and guide me what to do, step by step.


Source: (StackOverflow)

How to set wifi driver settings to prefer 5 GHz channel above 2.4 GHz

Currently I'm in a new building of my university. In this building my wifi often breaks down and then restores connection again. This is really irritating since it happens a lot.

Now as a coincidence there were some tech guys running around here and where asking everyone if the wifi was doing fine. I told them that my wifi tears down all the time and then reconnects. They figured out that my wifi is switching all the time between the 2.4 GHz channel and 5 GHz channel. They asked me if I could acces the driver settings of my wireless card. Unfortunately I don't know how to do this is in either Linux or Windows. And unfortunately again they only knew the windows solution xD.

So I hope somebody can tell me how I tell my wifi that it should stay on the 5 GHz network and not disconnect and switch to the 2.4 GHz channel?

-edit-

@arhimed, firstly thank you for your help.

I just tried what you said. It is some what different for me. I can't seem to save the settings when I change the setting and choose to use only the 5 GHz band.

"Network connections"->"Select the appropriate wireless network and click edit"->"In the wireless tab"->"Change the mode from infrastructure to ad-hoc"->"Choose 5 GHz band"

Wireless connection settings panel

However when I want to change the mode from infrastructure to ad-hoc the "save" button tells me that I have to authenticate myself. However I get no pop-up asking me for a password. Using sudo gnome-control-center didn't help either. I could still not save it. Also a error occured then in the terminal:

** (nm-connection-editor:5577): WARNING **: Invalid setting Wireless Security: Security not compatible with Ad-Hoc mode

Hopefully this is some usefull info for you to help me further.

--edit 2012/09/07-- Still no answer... Anyone?


Source: (StackOverflow)