Connecting to Optus@Home with dhcpcd and linux

Before we start..
If you're starting out with linux and just want a connection running A.S.A.P. then this page will do the deed.
However if your feeling adventurous then a floppy based router is an alternative.

October 23rd 2001: This page has been updated to reflect the new connection process
Optus have migrated the athome service to their existing optusnet network, this has involved server changes and most importantly for us, changed the connection methodology.
The co-30XXXXXX-a Client ID string is now redundant. The scripts that were referenced here have also been removed,

• Where is Optus?
• Introduction
• Security
• Before you start
• First step .. Manually connecting <=-- for the impatient ;-) -- this will be what you've come for....
• Automating
• Trouble shooting

Dhclient

It's worth noting that RedHat8.0 does not ship with dhcpcd anymore, it installs the dhclient program instead. You could install dhcpcd as follows or just use the dhclient rpm as it's more than adequate for the task. Most of the trouble shooting hints that follow apply no matter which program you decide to use. The usage for dhclient and optus can be found at the Metrak site (Basically it's /sbin/dhclient eth1 No "client id" should be needed)

The dhcpcd package is available here but it also comes packaged with RedHat and Mandrake as an rpm . Visit AARNet's local FTP archive for a list of available packages, whatever your Linux flavour.
The links for 6.x have dropped off the aarnet server so try the RedHat site or dig out your CD - it may be quicker!   The 6.2 rpm has been used with success for the 6.1 release. Don't worry, it works for the later versions too :-)

Before going much further it's worth mentioning that there is debate as to how well the Optus supplied NIC works. It appears that they've been supplying a different card since June 2000 that will fire up and talk to the servers. Mine wouldn't so I used a Dec204 (Etherworks3). Try the supplied NIC, and if you get it working let us know and I'll add it to the list. ( As of jan 2002 this issue seems to have died out, but be aware of the possibility )

The following procedure *should* work for most Linux flavour's.
Try it - I can't see anything getting fouled up from the command line - at least nothing that a kill command won't fix :-)

Manfred Bartz has some excellent material relating to firewalling and when your connection is working his site should be your next port of call.   There are many others, LSGA, the HowTo at Trinity or visit Linux Firewall and Security Site which has a wealth of information. The comp.os.linux.security FAQ is also worth bookmarking.

You can however treat Manfred's site as your "one stop shop" as it has many security related links besides a quick start firewall to get you up and running.

If that link came up with an error then the "www" needs to be substituted with your domain name. See the section on the next page. If you're outside the optushome network (using your old dial up account or viewing from elsewhere) then it will never work - it's an internal link.

These instructions should work for any Linux flavour

(1). Run which dhcpcd to find if it exists on your install. If it does then dhcpcd -v will give the version details (check with the above snippet to see if you're in the ballpark) otherwise visit one of the above sites.

(2). Read the man page man dhcpcd on the command line.

(3). From the command line enter.

/sbin/dhcpcd -d eth0

and you should get back a message similar to this ...

dhcpcd: your IP address = 203.164.18.133

which means that you are connected.
Where (pre october 2001) we once supplied a HOSTNAME, we will now be assigned one, so forget about inserting any client string or I.D.

The above is the procedure I used to connect a fresh install of RedHat 7.2 to the internet and is all that is needed since Optus changed servers and simplified the process.

If that didn't work then your in for a long read. On the troubleshooting page most of the problems you'll encounter get a mention, the most common is needing to reset the modem, it may pay to skim down a bit and view a brief summary as well. If the answer isn't there be sure to scroll to the top and review it all :-)

It also appears that the IP allocation will be purely dynamic now, when you reboot you will be allocated a new address, so no more static or extra long leases.

Once the manual method works and you're connected then you can automate the process.

=======8<=========

DEVICE="eth0"
BOOTPROTO="dhcp"
ONBOOT="yes"

This will enable the machine to connect and obtain a lease on system boot-up ( providing networking is enabled on start-up )
Other linux flavours should be the same, the file location may be different

Use YaST (at the command line) to configure the cards and associated system files and set the external card for bootp protocol (Network base configuration).
If you connected successfully with the manual method then /var/state/dhcp/dhcpcd-eth0.info is the dhcpcd generated file with dns server details etc.

Unlike RedHat there is no ifup or ifdown command for the interface. ifconfig with the appropriate options appears to do the trick; so ifconfig eth0 up will have the desired effect as will ifconfig eth0 down .