NetworkManager and system updates

After the official release of a distribution, the developers continue to iron out bugs with various patches, and they continue to minimize security vulnerabilities during the entire support period of the operating system. Ubuntu15.04, for example, will be supported for the next 9 months. If you install the distribution a few weeks after its official release, updates are already available.

To look for updates, call up the Software Updater program (Figure 1), which displays a list of installable patches. Clicking Install Now downloads the patches onto your computer (Figure 2). Restart the system to apply the patches. If no updates are available, you will see The software on this computer is up to date (Figure 3).

Figure 1: If Ubuntu updates are out there, you'll find out by invoking the "Software Updater" program.

Figure 2: Ubuntu shows details on what updates are waiting in the queue.

Figure 3: No updates are needed and you are good to go.

Bug fixes help keep your system safe and secure. With a few exceptions, such as Firefox and Thunderbird, newer versions of installed programs are updated with the next Ubuntu version. Within the support cycle of Ubuntu15.04, only Backports and PPAs [1] can be applied to a new version. Backports are special repositories that provide newer versions of some software [2].

Chicken and Egg

To get updates for Ubuntu15.04, you must have access to the Internet. The NetworkManager helps you set up that access during the installation. If you're not cabled in, the installer presents a window listing the neighboring wireless networks and asks you to connect to one, which is when installation begins in earnest.

To bypass this step, install Ubuntu without Internet access, and then later set it up through the NetworkManager, which is represented by a small icon at the top right of the screen. If you're using a wireless card, you will see a wave-shaped icon and, if the system is connected, the icon reflects the quality of the connection. Since Ubuntu 12.10, connecting to the Internet even before signing onto the desktop is possible.

Wireless Problems

Not all wireless cards work flawlessly with Ubuntu. Before you install Ubuntu on your computer, use the Live version to test whether Ubuntu recognizes your wireless chip. Boot into Live mode and try to connect to one of the wireless networks displayed. If connecting fails or no access points are showing, check the hardware switch on the computer itself.

If you run into problems configuring wireless cards, DSL modems, or UMTS sticks because NetworkManager doesn't recognize them, temporarily connecting the computer with a network cable to a switch or router usually works.

Hardware is a frequent source of wireless problems. On many notebooks, a button turns on the wireless card, whereas on others, a special key combination (e.g., Fn+F5) or a single F keystroke works. Test to see whether the WLAN has been deactivated by mistake.

To enable access for DSL, UMTS, and so on, click in the upper right on the NetworkManager icon and choose Edit connections . Through Connection information , you can find out whether the access point provided you an address via DHCP (Figure 4). DHCP (Dynamic Host Configuration Protocol) is the service that automatically assigns you an IP address in the local net. Most routers provide DHCP addresses by default.

Figure 4: Connection Information provides some helpful connectivity facts.