Working around UAC

Posted on By Mark Wilson

There’s been a lot written about Windows Vista’s user account control (UAC) and personally I can’t see what the criticsm is about (Mac OS X and Linux both have similar mechanisms, although the implementation is slightly different); however it was interesting to hear Steve Lamb mention at a recent event that commands launched from a command shell (cmd.exe) running as administrator will not invoke UAC.

Of course it goes without saying that, just as when running a root shell in Linux, the use of such sessions should be limited and I’ve written previously about how the shortcut to run cmd.exe as an administrator can be modified to make it very obvious that elevated permissions are in use.

Steve also pointed out that, if developers wrote less code that requires privileged execution, then UAC would not appear so frequently. Although UAC behaviour can be modified in group policy, it is not recommended.

Configuring wireless Ethernet with Red Hat Enterprise Linux 5

Posted on By Mark Wilson

Even Linux advocates admit that Linux is not as user-friendly as it should be when it comes to mobile networking:

“Networking on Linux right now is painful for the mobile desktop user, especially in comparison to other operating systems. A laptop user should never need to use the command line or configuration files to manage their network; it should ‘Just Work’ as automatically as possible and intrude as little as possible into the user’s workflow.”

GNOME NetworkManager project website

Oh how true!

A couple of nights back, I was staying at a hotel which only offered Wi-Fi connectivity for guest Internet access. That’s all very well if you have Wi-Fi configured on your laptop but, since rebuilding on Red Hat Enterprise Linux (RHEL) 5 last week, I haven’t got around to setting up the Intel PRO Wireless 2200BG adapter in my notebook. It turns out that it is pretty straightforward, once you have worked out what to do.

I recently wrote about configuring wireless Ethernet with Fedora Core 5 (using the same computer). After a long-winded effort, installing updated drivers, kernel modules and firmware, I finally got it working but only on one network and not with the NetworkManager applet. Then, I found out that the drivers are included in the kernel by default – all that is required is the correct firmware.

As it happens, the same is true for RHEL (lsmod | grep ipw2200 told me that ipw2200 and ieee80211 were both present in the kernel) and Jeff at nethub.org suggests (for CentOS, which is basically a rebadged version of RHEL):

“…download the firmware from the Intel Pro/Wireless 2200GB SourceForge project

[…]

After downloading the file, type in the following commands as root:

tar -zxf ipw2200-fw-2.0.tgz
mv *.fw /lib/firmware/
rmmod ipw2200

Then, wait a few seconds, and type:

modprobe ipw2200“

It’s actually even easier than that – the RHEL supplementary CD includes an RPM for the appropriate firmware (so why it’s not installed by default I don’t know) and, after installing the package and running modprobe ipw2200, eth1 became visible in my computer. Running service NetworkManager start and service NetworkManagerDispatcher start launched the NetworkManager applet too; although to make the change permenant, I used chkconfig NetworkManager on and chkconfig NetworkManagerDispatcher on. I also found that a reboot was required before all the wireless network components got themselves in order.

Following this, it was a case of selecting the appropriate SSID from the NetworkManager icon, and supplying the appropriate security details when prompted.

Network Manager - security

Following that, a connection was established (and NetworkManager even activates/deactivates the wired network connection as appropriate).

Network Manager - connected

It seems that getting wireless in Linux is becoming easier but it’s still not as simple as it should be. NetworkManager helps (a lot) but if the leading Linux distribution had automatically detected my industry-standard hardware (as Novell SUSE Linux Enterprise did… and as Windows did), it would have been a whole lot easier.