Yes I use NetworkManager. nm-tool showed the interface but marked as
disconnected. It also showed the usual set of wireless networks in
range including my own router. ifconfig, iwconfig and iwlist showed
what I expected (including 'iwlist wlan0 scan').
I did try to remedy the situation with iwconfig
(aiming to follow it with dhclient) but could not make a successful
connection. It may be I needed some additional argments to iwconfig:
I did use the correct essid, key and access point.

Now I'm back in business I can readily check that wpa-supplicant
is running, but I did not check it while stuck in single user mode.

----- Original Message -----
From: "zxq9" <[log in to unmask]>
To: [log in to unmask]
Sent: Wednesday, 18 July, 2012 1:45:05 PM
Subject: Re: X11 server won't start after yum upgrade

On 07/18/2012 07:28 PM, Malcolm MacCallum wrote:
> I knew about and used ifup (the device is wlan0). It did not solve the problem.

Wireless can be a bit different.

Are you using NetworkManager? If so, what is the output of nm-tool?
If not, is wpa_supplicant running on boot?
In any case, what is the output of ifconfig and iwconfig?
If everything seems in order, does "iwlist wlan0 scan" show you the 
wireless routers you expect to see?