[CentOS] Reliable way of having both LAN and WIFI on headless box

Fri Jan 13 11:33:51 UTC 2017
Gary Stainburn <gary at ringways.co.uk>

On Monday 09 January 2017 16:05:16 Gary Stainburn wrote:
> Once again I am building a headless Centos 7 box that needs to reliably be
> on both the LAN and WIFI network at all times.  Amongst other things it's
> going to be an AirPrint bridge enabling IPads to print to printers on a
> different VLAN.
>
> I have asked about this before and got a solution working using nmtui to
> set up both the LAN and WIFI interface, and activate them.  However, the
> WIFI link is unreliable. Sometimes it doesn't activate, or after a while
> de-activates.  Sometimes it doesn't even appear in nmtui to enable me to
> activate it.
>
> Can anyone help me with how I can set up a more reliable server.
>
> Thanks
>
> Gary

The server I was using was an old workstation PC that I re-used for this 
purpose.  I have now purchased brand new kit and done a clean install.

This box has now been running fine for a few days until this morning, when the 
WIFI dropped off again.  To investigate this I have had a look 
in /var/log/messages and I have found lots of entries.

At the bottom is where I re-activated the interface. 
Above that there are lots of entries where it toggles between inactive and 
disabled.
Above that at 09:33 there is an incident, and before that all looks normal.

I have posted the log here:

http://www1.ringways.co.uk/var_log_messages_WIFI.log

Can someone give me a clue how to fix this.

Also, it was suggested that I use nmcli in a cronjob to re-activate it if it 
drops.  I can check to see if it's still active by 'grep'ing the IP address, 
but I don't know the nmcli to re-activate an existing WIFI connection.

Can anyone help here too, just in case I can't fix the real problem