The properties for GDM are defined in the distribution-specific gconf settings in /etc/gconf/gconf.xml.vendor/%gconf-tree.xml.

To change the background image, look for:

<dir entry=”background”>

…

<entry name=”picture_filename” mtime=”1241629069″ type=”string”>

<stringvalue>/usr/share/backgrounds/glass/glass.xml</stringvalue>

</entry>

…

</dir>

Change the string value to the location of the background image you want to use.  This can be either a JPG file or an XML file in the Gnome background slideshow XML format (which does not seem to be documented).

The icon theme and Gtk theme can be similarly modified by editing the properties “icon_theme” and “gtk_theme” respectively.

It takes just 5 minutes to set up your OpenSUSE box up to synchronize its clock with internet time servers, ensuring that you never have to manually adjust the time again. Internet time servers use a protocol aptly named Network Time Protocol (NTP). In a default installation of OpenSUSE you should already have the software needed to communicate with NTP servers. You can check this by issuing the following command as root in a console:
rpm -q xntp
If installed, you should see the version number printed. If not, install the package using YAST2 or use this command (on OpenSUSE 10.2):
zypper install xntp

Step 1 – finding appropriate time servers

You ISP may provide a time server for you to use. This should give you the most accurate synchronization, as the time server should be close to you in terms of network distance. If your ISP does not provide a time server, you can use the pool of servers offered by the pool.ntp.org project. They maintain a list of public time servers and use DNS to distribute the load among the servers. To find the time servers appropriate for you, go to their main page og select the region you are in from the list on the right. Next, see if you can find your own country listed. You should end up with a list of servers something like this:
server 1.dk.pool.ntp.org
server 1.europe.pool.ntp.org
server 2.europe.pool.ntp.org

Step 2 – setting up the NTP daemon

As root, open /etc/ntp.conf in your favourite editor and paste the server list found above into the file under the section labelled “Outside source of time synchronization”. Save the file.

Step 3 – restarting NTP

Next, still as root, run the command:
service ntp restart

If your clock was out of sync, you should see it change. From now on, the NTP daemon will periodically contact the time servers and adjust your system clock so it is always accurate.

The problem is that when the router is started, it takes about 30-60 seconds before it initializes the connection and starts servicing DHCP requests. In the meantime the computer has already tried to get an IP address from DHCP. More importantly, it gives up trying before the router is up. In order to get a configuration for the network, I then have to manually force an renewal of the IP address.

I did not find a way to make the default DHCP client, dhcpcd, wait longer before giving up, without also causing the boot process to hang. Instead, I opted to use the dhclient, which is also installed by default but not enabled. This is done in /etc/sysconfig/network/dhcp where:

DHCLIENT_BIN=”"

is changed to:

DHCLIENT_BIN=”dhclient”

I also tweaked the options for dhclient a bit in /etc/dhclient.conf:

send dhcp-lease-time 3600;
request subnet-mask, broadcast-address, time-offset, routers, domain-name, domain-name-servers,
host-name, nis-domain, nis-servers;
require subnet-mask, domain-name-servers;
timeout 120;
retry 10;
reboot 10;
select-timeout 5;
initial-interval 2;
script “/sbin/dhclient-script”;

Now the DHCP client will run as a background process, waiting for the router to come up, but without slowing the boot process down.