Why does 18.04 not detect WiFi devices that 16.04 detects

[Mike Marchywka]

On Tue, Jul 09, 2019 at 12:31:39PM +0200, Liam Proven wrote:
> On Mon, 8 Jul 2019 at 13:58, Bret Busby <bret.busby at gmail.com> wrote:
> 
> > Personal denigrations help no-one.
> 
> It's an observation not a denigration. However, thank you for replying
> and falsifying it!
> 
> > As it happens, today, after coming back to the computer, after being
> > away (with my cellphone, that I use as a wifi hotspot for the
> > computers that have wifi, to access the Internet) for a couple of
> > hours, the network manager (I assume that it is the network manager),
> > or, otherwise, the icon in the panel, that shows the signal strength
> > for  wifi connections, and, the ethernet/wifi connection status, upon
> > being clicked, displayed the available wifi connection devices.
> >
> > Then, a few minutes later, it did not, again, showing just my cellphone.
> >
> > Then, a few minutes later, it again displayed all the available wifi
> > connection devices.

I have been through Ubuntu 11 ( on laptop with internal wifi) and Debian
on e-machine with wifi card or 'Beaver and now on new Precision with external
wifi antenna running Ubuntu 16.04. Somewhere in all of that I thought
I saw a huge delay in finding access points but never investigated.

I guess you could run iwlist a few times and see what it finds
with more frequenct scans. I guess it is also possible your phone
interferes and that varies with exact location or some quirk of the
driver. Maybe you could check frequencies in iwlist.   

 sudo iwlist wlo1 scanning  | grep Freq
                    Frequency:2.437 GHz (Channel 6)
                    Frequency:2.412 GHz (Channel 1)
                    Frequency:2.412 GHz (Channel 1)
                    Frequency:2.412 GHz (Channel 1)
                    Frequency:2.437 GHz (Channel 6)
                    Frequency:2.442 GHz (Channel 7)
                    Frequency:2.462 GHz (Channel 11)
                    Frequency:2.437 GHz (Channel 6)
                    Frequency:2.437 GHz (Channel 6)
                    Frequency:2.442 GHz (Channel 7)
                    Frequency:2.462 GHz (Channel 11)


> 
> So, it's an intermittent problem.
> 
> What you describe sounds a little to me like a poorly or
> intermittently connected wifi antenna. When the connection fails, it
> can pick up a very close signal -- the phone -- but not distant ones.
> 
> If this is the case, then trying other distro versions -- not
> installing, just booting -- will help to verify it.
> 
> > Oh, and, the reason that I had not gone into the BIOS/UEFI, or, booted
> > using a 16.04 iso image (all Ubuntu iso image discs, are LIVE, are
> > they not?), is due to having wanted to preserve the system state (open
> > web browser windows, etc), unless I absolutely needed to reboot (like
> > for a security update involving kernel upgrades).
> 
> Bookmark your tabs. Maybe use a browser-sync tool to make sure you can
> access them on another machine. You can even hibernate Ubuntu, if you
> have that enabled, to reboot and get into the BIOS.
> 
> (If it's not enabled, then enable it.)
> 
> However, booting a live medium will access your swap partition where
> the hibernated image is stored, so don't boot a live image on a
> hibernated system unless you don't mind losing the saved state. It
> shouldn't harm the install at all.
> 
> -- 
> Liam Proven - Profile: https://about.me/liamproven
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-- 

mike marchywka
306 charles cox
canton GA 30115
USA, Earth 
marchywka at hotmail.com
404-788-1216
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