These are the PLIP interfaces. PLIP transports IP datagrams over parallel lines. The interfaces are allocated by the PLIP driver at system boot time and are mapped onto parallel ports. In the
These are the AX.25 interfaces. AX.25 is the primary protocol used by amateur radio operators. AX.25 interfaces are allocated and mapped in a similar fashion to SLIP devices.
There are many other types of interfaces available for other network drivers. We've listed only the most common ones.
During the next few sections, we will discuss the details of using the drivers described previously. The Networking HOWTO provides details on how to configure most of the others, and the AX25 HOWTO explains how to configure the Amateur Radio network devices.
Ethernet Installation
The current Linux network code supports a large variety of Ethernet cards. Most drivers were written by Donald Becker, who authored a family of drivers for cards based on the National Semiconductor 8390 chip; these have become known as the Becker Series Drivers. Many other developers have contributed drivers, and today there are few common Ethernet cards that aren't supported by Linux. The list of supported Ethernet cards is growing all the time, so if your card isn't supported yet, chances are it will be soon.
Sometime earlier in Linux's history we would have attempted to list all supported Ethernet cards, but that would now take too much time and space. Fortunately, Paul Gortmaker maintains the Ethernet HOWTO, which lists each of the supported cards and provides useful information about getting each of them running under Linux.[20] It is posted monthly to the comp.os.linux.answers newsgroup, and is also available on any of the Linux Documentation Project mirror sites.
Even if you are confident you know how to install a particular type of Ethernet card in your machine, it is often worthwhile taking a look at what the Ethernet HOWTO has to say about it. You will find information that extends beyond simple configuration issues. For example, it could save you a lot of headaches to know the behavior of some DMA-based Ethernet cards that use the same DMA channel as the Adaptec 1542 SCSI controller by default. Unless you move one of them to a different DMA channel, you will wind up with the Ethernet card writing packet data to arbitrary locations on your hard disk.
To use any of the supported Ethernet cards with Linux, you may use a precompiled kernel from one of the major Linux distributions. These generally have modules available for all of the supported drivers, and the installation process usually allows you to select which drivers you want loaded. In the long term, however, it's better to build your own kernel and compile only those drivers you actually need; this saves disk space and memory.
Ethernet Autoprobing
Many of the Linux Ethernet drivers are smart enough to know how to search for the location of your Ethernet card. This saves you having to tell the kernel where it is manually. The Ethernet HOWTO lists whether a particular driver uses autoprobing and in which order it searches the I/O address for the card.
There are three limitations to the autoprobing code. First, it may not recognize all cards properly. This is especially true for some of the cheaper clones of common cards. Second, the kernel won't autoprobe for more than one card unless specifically instructed. This was a conscious design decision, as it is assumed you will want to have control over which card is assigned to which interface. The best way to do this reliably is to manually configure the Ethernet cards in your machine. Third, the driver may not probe at the address that your card is configured for. Generally speaking, the drivers will autoprobe at the addresses that the particular device is capable of being configured for, but sometimes certain addresses are ignored to avoid hardware conflicts with other types of cards that commonly use that same address.
PCI network cards should be reliably detected. But if you are using more than one card, or if the autoprobe should fail to detect your card, you have a way to explicitly tell the kernel about the card's base address and name.
At boot time you can supply arguments and information to the kernel that any of the kernel components may read. This mechanism allows you to pass information to the kernel that Ethernet drivers can use to locate your Ethernet hardware without making the driver probe.
If you use lilo to boot your system, you can pass parameters to the kernel by specifying them through the
ether=
The first four parameters are numeric, while the last is the device name. The
The first parameter sets the IRQ assigned to the device. By default, the kernel will try to autodetect the device's IRQ channel. The 3c503 driver, for example, has a special feature that selects a free IRQ from the list 5, 9, 3, 4 and configures the card to use this line. The
Different drivers use the next two parameters differently. For shared-memory cards, such as the WD80x3, they specify starting and ending addresses of the shared memory area. Other cards commonly use
The first non-numeric argument is interpreted by the kernel as the device name. You must specify a device name for each Ethernet card you describe.
If you have two Ethernet cards, you can have Linux autodetect one card and pass the second card's parameters with lilo, but you'll probably want to manually configure both cards. If you decide to have the kernel probe for one and manually configure the second, you must make sure the kernel doesn't accidentally find the second card first, or else the other one won't be registered at all. You do this by passing lilo a
reserve=0x300,32 ether=0,0x300,eth1
The
reserve=0x340,32 ether=0,0x340,eth0
You can turn off autoprobing altogether. You might do this, for example, to stop a kernel probing for an
