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In a recent installation of a minimal version of CentOS 7 (terminal only, no GUI), typing iwconfig results in the terminal showing a wlp3s0 connection, as follows:

[root@localhost wpa_supplicant_rpm_files]# iwconfig
eno1      no wireless extensions.

wlp3s0    IEEE 802.11abgn  ESSID:off/any  
  Mode:Managed  Access Point: Not-Associated   Tx-Power=0 dBm   
  Retry short limit:7   RTS thr:off   Fragment thr:off
  Encryption key:off
  Power Management:off

lo        no wireless extensions.  

But yet, when I type nmtui, then select Edit a connection, the Edit... option is not selectable. Why not? What specific steps do I have to take to make the wlp3so connection available to nmtui?


ONGOING WORK:


The rest of this posting includes many edits based on ongoing research. I am hoping the following research will enable someone to see how they can help me with this:

The possible approaches I have identified include:

1.) Possibly adding config files to /etc/sysconfig/network-scripts/  
2.) Adding a new connection using nmcli  
3,) Updating certain network management tools   

Here is a summary of what I have tried in each approach:


1.) Adding Config Files:


When I choose to either Edit a connection or Activate a connection from the first screen in nmtui, each of the resulting dialog boxes gives me the option to work with (add, edit, activate, delete) a wired connection that is defined in a file /etc/sysconfig/network-scripts/ifcfg-eno_backup. There are three ifcfg- files in /etc/sysconfig/network-scripts/ named ifcfg-eno, ifcfg-eno_backup, and ifcfg-lo (plus lots of other files with other types of names). Does this mean that there is some relationship between the ifcfg- files in /etc/sysconfig/network-scripts/ and nmtui? If so, how can we leverage this to get nmtui to see the wlp3so connection?


2.) Adding New Connection With nmcli:


Does it have to do with the STATE variable in the output of nmcli d? For example, this tutorial shows devices that are in the disconnected STATE showing up in nmtui, while a device in the unmanaged STATE does not. Similarly, when I type nmcli d in the CentOS 7 development server, the terminal repies with:

DEVICE    TYPE        STATE        CONNECTION
eno1      ethernet    unmanaged    --
lo        loopback    unmanaged    --  
wlp3s0    wifi        unmanaged    --  

So can changing the wlp3so state to something other than unmanaged help resolve this problem? Is this done with config files? Or with a tool like nmcli?

As further research, nmcli radio wifi results in the terminal printing enabled and nmcli device wifi list results in just another command prompt, indicating that wifi is enabled, but no devices are available.

I found instructions for setting up wifi and ethernet connections using nmcli at this link and at this other link. I imagine that setting up such connections might enable nmtui to see the connections, but I hesitate to try this without the guidance of someone on this site who knows about nmcli and nmtui. For example, is nmcli device wifi list failing to return results because some essential library is missing and needs to be installed first?

Typing ifup wlp3s0 in the terminal results in the following output:

/sbin/ifup: configuration for wlp3s0 not found  
Usage: ifup <configuration>  

3.) Updating Certain Network Management Tools:


When I google /sbin/ifup: configuration for wlp3s0 not found, I get this other posting, whose answer argues that the cause might be a driver issue.

This other unix.stackexchange posting reports that a similar problem was caused by incompatibility with a specific wireless card, and that the solution was to run yum install NetworkManager-wifi, but I cannot do that on the development server because it is not connected to the internet. Instead, I would have to download rpm files to another computer, transfer the rpm files to the development server, and then install them.

When I type lspci on the development server, the terminal replies with:

[root@localhost pciutils_rpm_files]# lspci
//lots of unrelated other stuff I am omitting for brevity
00:16.0 Communication controller: Intel Corporation 8 Series/C220 Series Chipset Family MEI Controller #1 (rev 04)
02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 11)
03:00.0 Network controller: Qualcomm Atheros AR9462 Wireless Network Adapter (rev 01)

The wifi card is an Atheros AR9462. When I googled for "Atheros AR9462 CentOS" the gist of the results was that CentOS supports Atheros wireless cards during install, but that some users see the wireless card disappearing from CentOS after install until they make changes. This blog entry states that the user resolved the problem by doing a fresh NetInstall of CentOS 7, but I hesitate to do that without guidance due to the problems the current CentOS installation is having with internet.

Given that one solution was yum install NetworkManager-wifi and another solution was to NetInstall and select the needed libraries during re-install, I downloaded NetworkManager-wifi-1.0.0-14.git20150121.b4ea599c.el7.x86_64.rpm from this link, then copied it into the development server and ran the following commands to install it, which seem to indicate that it installed correctly:

[root@localhost network_manager_wifi_rpm_files]# rpm -Uvh NetworkManager-wifi-1.0.0-14.git20150121.b4ea599c.el7.x86_64.rpm
warning: NetworkManager-wifi-1.0.0-14.git20150121.b4ea599c.el7.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID f4a80eb5: NOKEY
Preparing...                          ################################# [100%]
Updating / installing...
   1:NetworkManager-wifi-1:1.0.0-14.gi################################# [100%]
[root@localhost network_manager_wifi_rpm_files]# 

However, subsequently running nmcli dev wifi list showed no results as above, and typing nmcli device status showed the same unmanaged STATE as shown above.

  • At time of writing, nmtui does not support all types of connections. In particular, you cannot edit VPNs, Wi-Fi connections using WPA Enterprise, or Ethernet connections using 802.1X. Not sure how helpful this really is, thus not an answer but a 'comment'. Link is not public, but: access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/… – 0xSheepdog Sep 17 '15 at 21:46
  • @0xSheepdog Are you saying that nmtui cannot connect to a Comcast Xfinity cable modem? If so, how should I connect the CentOS7 development server through the cable modem? Another computer with windows host OS and CentOS virtualbox vm is able to connect via wifi to the same cable modem. – CodeMed Sep 17 '15 at 22:01
  • No, I'm not saying that, just sharing an interesting tidbit I found while digging around. I'm not a big fan of NM because it doesn't always get everything right. Is the device supported by Enterprise Linux? – 0xSheepdog Sep 17 '15 at 23:19
  • @0xSheepdog The CentOS 7 development server is trying to connect to a Comcast Xfinity cable modem. There are millions of these in North America, so I would hope that Enterprise Linux would know how to connect to them. Note that I continue to add research to my OP, including links. Right now, I am reading this: ask.fedoraproject.org/en/question/64217/… – CodeMed Sep 17 '15 at 23:22
  • I was talking about the local device on the server. I don't think the AP/radio-nic on the other end of the wireless connection really matters so long is it follows the standards or current practices. If the local wifi-nic isn't supported by the open drivers in EL, you may have to install vendor provided linux drivers (usually closed source, if you care.) – 0xSheepdog Sep 18 '15 at 14:11
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I have never had to use wireless until moving into this new home, and having to make due with the 802.11n card that I installed in the box a few years ago, for some reasons that I don't remember. I resolved all my issues with not being able to reliably setup wpa2-psk based ap connections with the installation of NetworkManager-wifi package. (yum install NetworkManager-wifi) This is not installed by default, and is the piece that was missing within my gui interface for wireless controls. (i.e. I couldn't setup wireless security, hence i never had a complete setup.) nmcli didn't seem to help much because the commands always seemed to work, but I ended up without an accurately configured psk, and hence I got the "no secret was provided" returned message when attempting to connect. I hope this assists anyone coming across this in the future.

I was able to setup all of the appropriate features that I just referenced within nmtui however, as I already indicated, it would never really get setup properly. As of 10-APR-2016, I was able to view the appropriate dialog for wpa2-psk, however, it was never fully associated in a way that I was able to seamlessly connect.

  • There was a simple solution. It involved manually setting a raw config. file, though I would have to research which one by digging through my other old postings of that time frame and also my notes. However, there was also a more involved solution that was to simply re-install CentOS 7 from the DVD, making sure to choose appropriate libraries and set enable wifi to true before launching the CentOS installation process. No config file changes were necessary after CentOS was installed with wifi enabled. But the easiest thing is to just connect an ethernet cable from the server to the modem. – CodeMed Apr 11 '16 at 16:38
  • Greet that you were able to resolve your issue during installation, CodeMed, however, if you install a newer (11n+) card in a few years on an old system which requires this config, as I did, you may have a better experience if NetworkManager-wifi is installed. I believe the nmtui was dependent upon NetworkManager-wifi also. – Martes Wigglesworth Apr 15 '16 at 23:43
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Add net.ifnames=0 to your kernel command line (via grub or whatever you use)

The issue involves the non-standard 'standard' names given to network interfaces. The net.ifnames=0 cmdline option reverts the network device names to the older conventional names. (eth0, wlan0, and so forth)

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