wireless interview questions
Top wireless frequently asked interview questions
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.”
What does this mean for me?
Wi-Fi is disabled.
Source: (StackOverflow)
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)
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?
Source: (StackOverflow)
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.
Source: (StackOverflow)
[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)
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.
Source: (StackOverflow)
I'm having serious problems installing the Broadcom drivers for Ubuntu. It worked perfectly on my previous version, but now, it is impossible.
What are the steps to install Broadcom wireless drivers for a BCM43xx card?
I'm a user with no advance knowledge in Linux, so I would need clear explanations on how to make, compile, etc.
lspci -vnn | grep Network showed:
Broadcom Corporation BCM4322 802.11a/b/g/n Wireless LAN Controller [14e4:432b]
iwconfig showed:
lo no wireless extensions.
eth0 no wireless extensions.
NOTE: Answer below is updated every time new information is added and confirmed working.
Source: (StackOverflow)
How to setup an Access Point mode Wi-Fi Hotspot?
Point to be noted: Wireless hotspots aren't the same as ad hoc networks. There is significant difference between the two. In short, ad hoc networks aren't supported on newer devices and most Android, Windows Phone and Blackberry devices (and maybe iOS devices too) whereas AP mode Wi-Fi hotspots are. To get an idea about AP mode hotspots, ad hoc networks and their difference, refer to this Wikipedia page and this article on Connectify website.
Source: (StackOverflow)
Your situation
- You have successfully installed Ubuntu.
You have just downloaded and booted Ubuntu live media.
The latest LTS (see also HWE) or latest non-LTS release are preferred. See the list of Ubuntu releases that are currently supported.)
You upgraded your Ubuntu installation to the latest release that the software updater offered you. WiFi worked before, but not now on the new release.
- You migrated your existing Ubuntu installation to new hardware.
Your problem
- The wireless of your laptop or dekstop is not working. You tried switching the wireless switch off and on and you tried rebooting several times, but you don't see any WiFi access points.
- You can see your wireless access point, but you cannot establish a connection.
- You want to analyze the problem, but you don't know where to start or what information you can provide.
This question and answer was written to give people the wireless script that will provide the information needed in most cases to diagnose their wireless issue's.
Related questions
Source: (StackOverflow)
I know how to create a hotspot when connected to a wired network, but when I am using internet from a WiFi connection, this disconnects the wireless connection the moment I activate the hotspot.
In Windows I can use Connectify Hotspot, which enables me to share the internet connection from the same wireless adapter as I am creating an access point on. As you can read on the technology overview page:
Access Point mode allows you to create a hotspot using the same Wi-Fi card that you are using to access the Internet.
How do I do this on Ubuntu?
Source: (StackOverflow)
I just updated to Ubuntu 12.04 from 11.10 but soon after updating I was disappointed to see that
Wireless is disabled by hardware switch.
I can not click the button 'Enable wireless' which is greyed out. Without wireless my computer is useless as I have to connect by wire which is not practical. I have a Acer TravelMate 4500
Source: (StackOverflow)
Other posts seems to be addressing more complicated network connection issues from the command line.
The Unity panel Network indicator/button doesn't respond too well sometimes - it keeps trying to connect to a network even when i click on "disconnect", stuff like that.
So I want to go command line for the control. I don't like GUIs anyway.
Is there not some simple command line tool which can do something like the following?
wifi connect MyNetworkNameA
wifi disconnect
wifi connect MyNetworkNameB
Source: (StackOverflow)
I want to share the wireless Internet connection on my desktop with my old laptop, through ethernet.
I have ticked the option "Make available to others" on both connections, on my desktop, but my laptop doesn't connect. Am I doing something wrong or is it a bug?
Source: (StackOverflow)
That's pretty much it. If I connect to the Internet on wlan0, how can I share this connection with a device plugged into my wired Ethernet port eth0?
Source: (StackOverflow)
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)