Janou's ADSL EASY-HOWTO for Linux Systems
v0.1, September 4th 1999.

ADSL - Asymmetric Digital Subscriber Loop (ADSL), is a fairly new, high-speed digital access line technology available from Telcos. ADSL is one of a family of digital subscriber line (DSL) technologies available to residential and business customers using existing copper lines, providing speeds from 256kbps upstream to 1.5Mbps downstream. After spending hours of surfing the web and getting information on ADSL and Cable, I decided to go wit hthe ADSL (but really because broadband isn't in my area).

Though both are copper, technically, Coaxial cable is a much better conductor with less resistance than normal copper wire such as telephone lines. What makes Coax even better is that it is sheilded. In my opionion, cable will get faster speeds than adsl, but one thing you have to keep in mind ... cable service is a shared connection and the more the group in that shared grid grows, the slower the data rate will become, up and down. For ADSL, it is somewhat of a single direct conection to the ISP station over copper loops. It has much less fluctuation than cable. So, in the long run, the more and more people subscribe to cable, the slower it will become. Well, enough of that (I don't want to be biased).

When you subscribe for ADSL service, all you need to do is wait for the installers to come and reak havoc to your system. What they will generally do is install a "line splitter" onto the phone line junction, either outside of the house or in a crawlspace. Tell them that you want a "Home Run" line ran to a new modular. What they will try to do to make their job easier by "tapping in" to an existing drop and run it from there. THIS IS NOT GOOD. If the wires that they are jumping off of is old, there can be a lot of resistance in them. It is your money and your choice. Don't be afraid to tell them that you want a new line ran.

Once they complete the wiring, they will access your system, and install the LAN card. This is included in most installations along with the ADSL modem box. Once they are out of your way and out of the house you can finally get started on the good stuff.

INSTALLING IN THE LINUX BOX
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If they installed the NIC card on a windows machine and you have a separate Linux box, you need to take out the NIC card and put it in Linux. First remove the drivers from the control panel networking section. After you place the new card in, do the following:

As root user, type linuxconf

Goto Networking --> Basic host Information. If you already have a network card in the system and you just put the second one in for ADSL, then you will need to make eth0 the ADSL and eth1 the LAN. You DO NOT have to take out the cards for this.

Simply type what you see in eth0 into eth1's section. Then in eth0, choose;

Config mode = DHCP (I will be surprised if it's a static IP)

Primary name + domain = This can stay blank

Alias (opt) = leave Blank

IP Address = Leave blank (It's dynamic ... or in most cases, it is)

netmask = 255.255.255.0

Net device = eth0

Kernel Module = (this is the driver for your ethernet card. If you're not in x, press ctrl+x. You will get a menu to choose from. This way, you won't key in the driver name wrong)

Leave everything else blank.

Accept the changes and leave the Basic host information section.

Next modify your /etc/resolv.conf file. This can be done right in linuxconf by going into the Name server specification (DNS) section. You may remember this from your ppp setup. What you need to do is change the existing DNS servers to the new ISP's DNS. (If you have the same ISP as you did when you had dial-up service, still check because sometimes, the dialup can be different. Most cases, it isn't).

In nameserver 1, place the primary DNS IP address that was given by your ISP (e.g. 192.0.0.1)

If there is a secondary DNS, place that in nameserver 2

For search domain 1, you can type in the name of your ISP host, (e.g. bellsouth.net, mci.com, etc). This section is usually resolved automatically, but it doesn't hurt to put it in.

The DNS information will be written to the /etc/resolv.conf. If you wish to bypass linuxconf, you can edit the file directly using "pico".

You do not have to set up routing and gateways unless you're routing to another LAN or remote.

Now, it's time for the test ...

Once you accept the changes in linuxconf and exited, type:

/sbin/ifconfig

This should show eth0, eth1 and lo

Take a close look at eth0. You should see something similar to this:

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eth0      Link encap:Ethernet  HWaddr 00:50:DA:06:CB:35
          inet addr:216.78.110.103  Bcast:216.78.110.255  Mask:255.255.252.0
          UP BROADCAST RUNNING  MTU:1500  Metric:1
          RX packets:17258 errors:0 dropped:0 overruns:0 frame:0
          TX packets:11104 errors:0 dropped:0 overruns:0 carrier:1
          collisions:1 txqueuelen:100
          Interrupt:11 Base address:0xec80

eth1      Link encap:Ethernet  HWaddr 00:60:8C:E8:3F:DE
          inet addr:200.200.200.21  Bcast:200.200.200.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:12401 errors:2 dropped:0 overruns:2 frame:2
          TX packets:12108 errors:0 dropped:0 overruns:0 carrier:0
          collisions:1 txqueuelen:100
          Interrupt:5 Base address:0x300

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:3924  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0

This means that your ADSL connection is receiving a signal. You can see your assigned IP address in the inet addr. You can also get your ip address by using the "dhcpcd" command. (e.g. /sbin/dhcpcd -h bellsouth.net). Replace the "bellsouth.net" with your host or isp domain name.

Now, you can do the ultimate test and go onto netscape and pull up a website. Or you can ping a few domains and see the response.

That is really all to it. If you are masquerading across the network, and if eth1 was the NIC card gateway to the other machines, all you have to do is change the DNS and host on those systems. The gateway IP stays the same.

Happy ADSL'ing !!!

SirPlaya

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