Here's an embarrassing one - sorry, I have searched.

I have a working broadband connection via a router/modem, that comes up automatically when booting and works fine. But my pc also has a modem in it, which I keep in case my broadband ever goes down.

For the dial-up, I have done what I think is the hard bit - I've waded through all the modem how-to's, identified my modem chipset, found a driver, installed it and recompiled the kernel; I've set up an account with kppp and connected successfully to my ISP on dial-up, using kppp.

But - how do I make my web browser use the dial-up connection? In Windows my browser and my email client also preferentially use that the broadband connection, so I go to the network bit of the control panel, and 'disable internet connection'.

What's the equivalent for Linux?

Temporarily or permanently?
ifdown eth0
then start your dialup connection.
Disconnect from your dialup, then,
ifup eth0
would be a temporary solution.

Thanks. Yes temporary, for testing purposes. I assume this won't be a problem when I really need it, i.e. when broadband is actually down.

But, ifdown gives me a bash: command not found
No man ifdown.
Can't find 'ifdown' on my system, if it's a script.

I assume from the command that if I could do it, it would disable my NIC, so I wouldn't be connected to my home network either - not necessarily the end of the world by any means, as this is only for extraordinary use - but the Windows equivalent only takes down the broadband connection, and leaves my lan network connection alive.

But I think I am being even stupider than I thought - I can use my router config to take down the broadband connection, of course.

But then I still don't know how to get my browser to use the dial-up connection. It doesn't seem to automatically find it when started up. I've tried with Konqueror and Mozilla.

On IE, I'd use Tools-Internet Options - Connections to pick which one it uses, but I can't find anything similar in my Linux browsers.

How stupid - this really is embarrassing.

I have used the ifup and ifdown command on Debian, Suse, and Mandrake. I am not 100% sure it is available on Slack, would think it is.
You would need to issue the command as root.
Do you know how to use the su command in a terminal?

Yes I do, but did it as root anyway.

Hang on .... OK I've found the equivalent now for Slackware, it's ifconfig, and it takes down and up parameters. Right, you got me in the right direction for taking out my ethernet connection, thanks.

I still don't know how to get my browser to recognise the dial up connection, after I've taken down the broadband and dialled up.

It maybe as simple as removing your existing default gateway for eth0

route del -net default gw 192.168.1.1 (or what ever it is for eth0)

but I don't have the setup your describing to mess about with

ifconfig eth0 down

on slack

Right, well I've kind of cracked it.
1. At prompt, ifconfig eth0 down
2. startx to KDE
3. kppp to dial up
4. Konqueror then will browse
5. Logout and reboot, to get it working on broadband again

If, after closing Konqueror I exit KDE and do ifconfig eth0 up, then I do get my ethernet connection back, but I must have lost more than that when I took it down, because Konqueror is all confused and can't browse. So I have to reboot. Ah well, it'll do in an emergency I suppose, though why it isn't possible to direct the browser to a known connection is completely beyond me.

In the process I thought there may be some configuration of the browser required - I can't find anything like that for Konqueror.

I did find the config stuff for Mozilla. Now Mozilla is totally broken, it just offers me 2 profiles when I try to start it (one of which is the one that previously worked) then hangs as soon as I pick one.

This is all round pretty useless, really.

Well, I searched the forum and found that Mozilla frequently corrupts its profile and the thing to do is just to delete it and let it create a new one next time it gets started.

Which I have. Now I can use a sort of default Mozilla, though I find that it won't submit searches to Google - it browses web pages OK, when entered in the url field, but seems not to know how to submit text in a text box using get or post whatever - Mozilla is a joke.