Firefox failing to recognise Rockwell IQ148 modem connection

Q I cannot get Firefox to 'see' the modem connection that I've painstakingly set up. I'm fairly sure that it's working correctly, as running pon from the command line causes the modem to dial out, and poff makes it hang up. However, activating Firefox from the desktop is the problem. The Ethernet connection to broadband works fine, but disabling it and making the modem the default connection brings up the 'server not found' screen. The modem is a Rockwell IQ148 and I'm using Ubuntu Dapper 6.06. I'm trying to set up the computer for my partner, who doesn't have broadband but has been gradually converted from XP by using my machine.

A This is almost certainly a general problem with your internet connection and not specifically related to Firefox. It sounds like your system is still trying to use the Ethernet connection. Type this in a terminal:

route -n

The line we're interested in is the last one beginning '0.0.0.0' as this is the default route for all non-local connections. I suspect it looks something like this:

'0.0.0.0     192.168.0.1 0.0.0.0         UG 0
0      0 eth0'

The last two numbers in the second string will probably be different, but if it ends in 'eth0' (or anything but 'ppp0') this is the cause of your troubles. You need to make sure the eth0 settings are purged from your system, especially if you'll no longer be using Ethernet with your broadband provider, by selecting it in the Network Settings window and pressing the Delete button (the middle of the three obscure-looking buttons at the top-right of the window). Another possibility is that your modem connection hasn't completed. The fact that the modem dials out doesn't guarantee that a connection is made. Try running

sudo plog

after an apparently successful modem connection. This will show you the last few lines of the connection log: it should be obvious if anything has gone awry here. You can also check the status of your network connections with

/sbin/ifconfig -a

If the eth0 interface appears, it shouldn't be marked 'UP' nor have an 'inet addr' entry. Equally, ppp0 should be marked 'UP' and have a valid address. It's also possible that you're connected to your ISP but not able to look up internet domain names. Run these two commands in a terminal:

ping -c 5 www.google.com
ping -c 5 216.239.59.104

The first attempts to contact Google by name, the second bypasses the DNS lookup and goes directly to its IP address. If only the latter works, your DNS information hasn't been correctly set up. You'll need to contact your dial-up ISP and get the addresses of the DNS servers, then put them into the file /etc/resolv.conf. It should look something like:

nameserver 1.2.3.4
nameserver 1.2.4.5

You can either edit the file directly or use the DNS tab of the Network Settings tool. It's possible you still have your broadband ISP's name servers in here. These should be removed.

Follow us on Identi.ca or Twitter

Username:   Password:
Create Account | About TuxRadar