MJPye.org.uk Logo

Home Page
Networking Home Page

Setting up Acorn TCP/IP networking

Before we attack any software, it's best to write down a basic map of what we want to achieve. We need to sort out the physical cabling and to assign IP addresses and names to each machine. Here's a diagram of a simple typical home network, using 10base2 cabling.

[Image 1]

We have a RiscPC in Room1, with a modem, giving Internet access. This machine is at one end of the 10base2 network, so has a terminator. Room2 has an A310. Room3 has an A440 with a Deskjet printer. The A440 is at the other end of the 10base2 network, so has the other terminator. Note how at the A310 we "see" two cables going to the machine. It may be tempting to shorten the cables from the RiscPC and A440 and put a T piece with a long spur cable going to the A310. This is not allowed. The cable must be one long run, going right to the back of each machine. We'll now assign some names and IP numbers to these machines:

[Image 2]

I always find it useful to give an alphabetic progression of names, so that the ".1" machine has a name with an 'a', ".2" is "b" and so on. That way, it's easier to remember what IP matches what name. You may choose to name your machines depending on who uses them, where they're located etc. Here's the list for our example:

192.168.1.1    aardvark
192.168.1.2    bear
192.168.1.3    cheetah

It's also handy to name your network. We need to be mildly careful about this, if we're contemplating any sort of Internet connection from any of the machines -- you don't want to end up with a name that is the same as a real host on the Internet! Anything ending in .com, .org, .net, .co.uk, etc is a bad idea. One of the most common names I've seen used for a private home network are those ending with ".home". That seems sensible so we'll call this network "my.home". We can write out the full machine names now:

192.168.1.1    aardvark.my.home    aardvark
192.168.1.2    bear.my.home        bear
192.168.1.3    cheetah.my.home     cheetah

You'll notice that I've laid out this list in a careful way. IP address first, then the full name, then an abbreviated name. What you have there is the "Hosts" file that should be used when setting up the software on each of the machines. We also need to add one last item to this "Hosts" file -- a loopback host -- this is the same for all machines so we can add it to the hosts file:

127.0.0.1      localhost

192.168.1.1    aardvark.my.home    aardvark
192.168.1.2    bear.my.home        bear
192.168.1.3    cheetah.my.home     cheetah

Now we can configure the software! As I said earlier, I'll presume everyone has the New !Boot application installed, so either run !InetSetup from ResourceFS (the 'Apps' icon) or run !Boot and choose "Network". Either way, you should end up with a window looking something like this:

[Image 3]

For file sharing, we need to enable Acorn Access, so click on "Access" then tick the box labelled "Enable Access" and click "Set":

[Image 4]

Next comes the main IP set up. Click on "Internet" and this window should appear...

[Image 5]

You should ensure that "Enable TCP/IP Protocol Suite" is ticked. The next thing to do is set up the hardware interfaces. For now, we shall ignore any dialup facilities you may require, and concentrate on Ethernet. Click on "Interfaces" and the following window is displayed:

[Image 6]

The "PPP" (Point to Point Protocol) will always be seen, as all computers have serial ports which could potentially have modems connected. Any ethernet cards found in your machine will also be listed. In this example, our RiscPC, aardvark, has an ANT Ether3 podule in slot 0. Tick this box, then click on the "Configure..." button to the right and you will see the device configuration window:

[Image 7]

Ensure that this dialogue box is set up as above. The Netmask should be 255.255.255.0 for our network, which is "default" anyway. Ensure that the IP address is obtained by name (we will set the name later on). Click on "Set". Now we will set up the routing. Click on the "Routing" icon and you will see the routing setup window:

[Image 8]

For our small network, we don't really want any routing, but for future use, it's best to set the "Gateway" to be the IP of the machine with the modem. For our network, this is 192.168.1.1 -- all machines should be set to have the same Gateway IP. We don't need to do any other routing just now, so ensure "Act as an IP router" and "Run RouteD" are not ticked, then click on "Set". Next we will set up the host names. Click on "Host names" to see the configuration window:

[Image 9]

In the "Host name" field, enter the name for this computer. The image above was taken from the machine to be set up as aardvark. For local networking, we don't need (or want) to use a NameServer, so click the "Use hosts file only" box. Finally we need to set up that "Hosts file", so either drop a copy of the "Hosts" file you created earlier while designing the network where the window shows, or, click on "Hosts file..." and edit the textfile. Make sure that the files on all the machines are the same! Finally, click "Set"

That's it! Click on "Close" on the "Internet configuration" window, then on "Set" on the "Network configuration" window. Reboot your machine, and you're done!

Follow the steps above for all your machines -- all the details should be the same, apart from the "Host name" you give each one (in our case, aardvark, bear, cheetah).

Once all machines are set up and have been rebooted, you can check everything is working by pushing F12 and typing * FwShow. This should produce a list similar to this:

No remote nets

Type 5: (Hosts)
   *Name=aardvark   Holder=192.168.1.1
    Name=bear       Holder=192.168.1.2
    Name=cheetah    Holder=192.168.1.3

Type 1: (Discs)

Now what we want to do is get those discs shared! Some Ethernet cards will provide a new version of "ADFSFiler" for you, which gives a new option on the icon-bar filer icon for each disc, "Share ->" You can use this to share a disc (usually unprotected). If you've not got this facility then you can use the * Share command to share a disc, or a directory. It's commonplace to share a disc giving it the same name as the disc. Alternatively, you could use the machine's name, or some other useful identifier. Here's how we share the disc in aardvark as 'Aardvark':

*Share ADFS::4.$ Aardvark
You can put these commands somewhere useful in your !Boot sequence, but bear in mind that the Internet suite is not initialised until the !Boot.Choices.Boot.PreDesk.SetUpNet file is run, so it's best to create an Obey file of *share commands and put that in !Boot.Choices.Boot.Tasks

After sharing discs, they should show up via the * FwShow command:

Type 1: (Discs)
   *Name=Aardvark   Holder=192.168.1.1
   *Name=Work       Holder=192.168.1.1
    Name=Bear       Holder=192.168.1.2
    Name=Cheetah    Holder=192.168.1.3

Note here that we've got two 'discs' shared from the same machine -- aardvark shares it's whole disc, and also a subdirectory somewhere in the heirarchy called "Work". This is so that other machines can quickly locate the "Work" directory on Aardvark, rather than going from the top level every time. What shares you make depends on what you want to do with your network, how much you trust other users, and what you don't want folks on other machines being able to access!

Now you can use the shared discs as if they were real harddrives on the machines. You should have a "Discs" icon on the iconbar now, click on it to display the shared discs on your network:

[Image 10]

Double-click on any of the available discs to connect to it -- the "Discs" icon should change to show whatever you selected. Click on the iconbar icon again, and a filer window for that disc will open. To connect to more discs, just double-click on the icons in the disc display window. (If the window has closed, click 'Menu' on the iconbar icon, and choose "Show discs"). Once you're done with a shared disc, dismount it from the iconbar menu, just as you would with a floppy disc.

That concludes the very basic tutorial. Next we will move on to Access+ with restricted control, and on to sharing Printers.


ian@eh.org

This page was written by Ian Jeffray and hosted on his website until 2002, it is now available here with permission
MJPye.org.uk site design and layout Copyright 2003
Matthew Pye. All Rights Reserved.