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Install Regarding the Hardware you first have to check if your network card is really supported by the Linux-based Sun Java Desktop System. Please consider the following categories: PCMCIA kernel or external, PCI, WLAN-NG, and USB. Not all of these are currently supported under Linux. So you may want to check the following website for an overview of running projects: http://www.hpl.hp.com/personal/Jean_Tourrilhes/Linux/Wireles s.html (Another Linux Wireless LAN Howto can be found there as well) Most wireless LAN PCI and PCMCIA cards are supported by the Sun Java Desktop System. The most four common big manufacturers of wireless LAN chipsets are Lucent Cisco Intersil and Atmel. The first three cards work mostly with the "orinoco" (http://sourceforge.net/projects/orinoco/) module. This module is available for cards based on PCI and PCMCIA (both systems kernel/external). PCI-based cards should operate with "orinoco", PCMCIA-based cards with "orinoco_cs". Atmel manufactures chips for USB cards. Introduction - Wireless Extensions Before the 'ordinary' network setup of the card, there has to be a set up of the wireless extensions. All modules can be controlled with the tool iwconfig (except WLAN-NG). Please enter "man iwconfig" (w/o qoutes) in a terminal window for more details. Also the Java Desktop System Configurator enables you to change the wireless network card configuration comfortably. This can be done through [Launch] - "Preferences" - "System". In the appearing dialog, please double-click on "Hardware" and then again on "Network Card". Your card may not be automatically detected. In this case select the entry "Other (not detected)" and proceed with [Configure...]. If you check on the "Wireless device", the [Wireless settings] button is active. Once pressed, you can define various parameters: Wireless LANs can be situated in different operating modes: - Ad-hoc - The wireless LAN may consist of several computers with wireless network cards that directly communicate with each other. From the single computers point of view, the network is composed of only one cell without an access point. - Managed - The network is composed of many cells with an access point (independent hardware component) or with roaming. All wireless LAN clients are connected through this access point, not directly with each other (managed). Access points could also offer the possibility to connect the wireless LAN to a conventional wired network. An integrated DSL router could be also included. - Repeater - The node forward packets on the air. - Secondary - The node acts as a backup master or repeater. - Automatic - Automatic decision between one of the previous modes. Thereafter additional parameters have to be defined. Please read the detailed explanation of them on the left description bar inside the dialog, if you can not wait any longer. Otherwise more details will follow later on in this document. After pressing the [OK] button you are back on the previous dialog. If the "Wireless device is still checked, the button under "Kernel module" named [Select from list] offers you some already included wireless kernel modules, if you are not using USB or PCMCIA. Before you try to configure the network based on wireless extensions, the wireless extensions must have been configured and run! Apart from this, the wireless network does not differ from a wired network. Network cards can be addressed like eth0, eth1 with ifconfig or ip. Setting up PCMCIA or USB The Sun Java Desktop System should virtually detect all wireless LAN cards or cards connected through USB. The corresponding module will be automatically loaded. You can follow the action by observing the file /var/log/messages through a terminal window: tail -f /var/log/messages If this the automatic detection does not happen, please contact Support and send them the messages file additionally to detailed information about the card and your system. Alternatively you can also use the command lsmod to see all the loaded modules, when the card has been inserted. If the module loads successfully, the cards are visible with the commands "ifconfig" and "iwconfig". Then you can easily set them up via the on top introduced menu call ([Launch] - "Preferences" - "System" - "Hardware" - "Network Card" - [Configure...]). You can now enter the corresponding module and configure all options relevant to wireless. After confirming your settings, there will be an entry in the file /etc/modules.conf created, defining which module is responsible for the first network device and announces this to the kernel (depmod -a). The command alias eth0 pcimodule is all you need to fix the hardware settings for PCMCIA cards permanently (assuming this is your only network card). Setting up PCI You can use the command "modprobe" in a terminal window, if you know the right module for your card. Type something like the following, to test if the module can be loaded: modprobe pcimodule If the module loads successfully, the cards are visible with the commands "ifconfig" and "iwconfig". Then you can easily set them up via the on top introduced menu call ([Launch] - "Preferences" - "System" - "Hardware" - "Network Card" - [Configure...]). You can now enter the corresponding module and configure all options relevant to wireless. After confirming your settings, there will be an entry in the file /etc/modules.conf created, defining which module is responsible for the first network device and announces this to the kernel (depmod -a). The command alias eth0 pcimodule is all you need to fix the hardware settings for PCI cards permanently (assuming this is your only network card). Setting up WLAN-NG The interfaces of the kernel modules for Intersil cards are completely different and would therefore not work together with the Java Desktop System Configurator. Also the tools for "normal" kernel modules like iwconfig do not work in this case. Please lookup the WLAN-NG project homepage (http://www.linux-wlan.org) for own tools like "wlancfg" or "wlanctl-ng". The Java Desktop System Configurator is designed for the use of "iwconfig" for a simple reason: All cards with a Prism(2) chipset also work with the "orinoco" module. If you want to operate a card with the WLAN-NG modules, you must perform the configuration manually. For this purpose, please refer to the WLAN-NG-README available at ftp://ftp.linux-wlan.org/pub/linux-wlan-ng/README. Wireless Parameters The ESSID is absolutely needed for a wireless LAN, since there are only a few radio frequencies available. Multiple existing networks are separated from each other through the ESSID (which resembles the name of a network). So logging into a existing wireless network requires the knowledge of its ESSID. If you start the network, the ESSID must be carefully selected. Sometimes the effect of easy applying to a wireless network is wanted. In these cases, it is enough to set the ESSID as "any" and the card will use the first ESSID which is found. To verify parameters are set correctly you can look up the output of the command "iwconfig". You should see the ESSID followed by your specification as well as a defined Mode with e.g. the state "managed". More parameters are: Nickname - The Nickname of the card/computer. Please do not mix up with the host name. Frequency - The broadcast frequency of the network Access Point - The Ethernet hardware address of the access point currently in use. Bit Rate - The Speed of the existing wireless LAN. Encryption key - The encryption key in use. Link Quality - The connection quality to the access point. Noise Level - The amount of interference in the radio transmission. The settings done in the "Wireless network card configuration" of the Java Desktop System Configurator are written to the file /etc/sysconfig/network/ifcfg-{hardware}-{number}. There are some more additional variables which cannot be set using the Java Desktop System Configurator. A complete overview of possible parameters is available in the file /etc/sysconfig/network/wireless. Network Setup Now it is time to continue with the 'real' network setup. You should still be in the Java Desktop System Configurator at the "Manual network card configuration" dialog. Now press the [Next] button. If you simply want to connect two wireless LAN computers in ad-hoc mode, it is enough to set the wireless extensions of both machines to the same values. If they are different types of cards, this should be considered, of course. You can use the "Static address setup" and assign different IP addresses from the same subnet preferably "192.168.x.x" to the cards. For example "192.168.0.1" for one computer and "192.168.0.2" for the other. The subnet mask default value of "255.255.255.0" is correct for both. Defaults for the computer name and the routing can remain unchanged. After having also checked that the radio connection between the computers works, both machines should be able ping each other. For managed wireless networks with access points the procedure could be the same except for the mode, which must be changed in the wireless settings. Also you may want to use the "Automatic address setup (via DHCP)" feature. After you have set all this options the Java Desktop System Configurator writes the network configuration including the wireless configuration in the corresponding ifcfg file. Open the file /etc/sysconfig/network/ifcfg-{hardware}-{number} in your favorite editor to see the contents. The file can be edited for custom changes to set parameters which are not handled through Java Desktop System Configurator. Thereafter the card can be restarted with the commands "ifdown" and "ifup". Please refer with the command "man ifup" to its man page and please also lookup the file /etc/sysconfig/network/ifcfg.template. Troubleshooting - General Additionally to the 'normal' network problems, which also may arise in a wired network (please consider reading a Linux Networking HOWTO available for example at http://www.tldp.org/HOWTO/Net-HOWTO/index.html), there is also the radio transmission problem-factor (microwaves, mobile phones, TV's), next to false wireless settings including WEP encryption. We recommend for troubleshooting, always to check the noise level and the link quality first, before looking into your hardware or network settings. Troubleshooting - Hardware All known cards with Prism(2) chipsets were removed from the WLAN-NG system. But there might be still an unknown card for which a WLAN-NG module is loaded by the PCMCIA system. This could be one of the following modules: "prism2_cs", "prism2_pci", "prism2_plx". Additionally the network device is called "wlan0" instead of "eth0". To avoid this wrong setup, the PCMCIA system can be informed that the "orinoco" module must be loaded for this card instead. You first need to find out the card ID with the following command (assuming that you have the "PCMCIA support for Linux" RPM installed): cardctl ident The output of the command might be also interesting for our support staff. An example output could look like this: Socket 0: product info: "D-Link DRC-650 11Mbps WLAN Card", "Version 01.02", "" manfid: 0x028a, 0x0002 function: 7 (wlan-ng) Now open in your favorite editor the file "/etc/pcmcia/wlan-ng.conf" and search for "manfid", the card code. Disable everything related to the output of the "cardctl ident" comand by using the hash mark comment sign and save the file. After that, create a new entry for your card in the file "/etc/pcmcia/config". Please search for other entries related to "orinoco" modules and append the new entry to them. In our example it is: card "D-Link DRC-650" manfid 0x028a, 0x0002 bind "orinoco_cs" Finally you can restart the PCMCIA system with the command "rcpcmcia restart" from a terminal window. The correct module will be loaded and can be set up with the Java Desktop System Configurator. |