5.7 Using Dialup

[The ttylinux PPP and ISDN structure is being re-organized.]

What to put into /etc/isp.conf to configure the dailup information is outlined above in the customization section (3.3, above). What you will find here is an overview of how to actually use the PPP subsystem for Internet dialup.

Assuming /etc/isp.conf was setup correctly before boot, you only need one command to start up the Internet connection:

	ppp-up

If you use ISDN with autodialing enabled (ISDN_MODE=auto set in /etc/isp.conf), you do not need to run ppp-up. Just run a program that sends packets to an Internet host.

ppp-up triggers the PPP daemon, which will dial the provider and try to login. ppp-up can be run by any user in the ppp group. In the default ttylinux configuration, the ppp group has no members, so only root can start and stop the internet connection. You can watch /var/log/messages (using tail -f) to see when the connection is up and running. After that, the Internet connection is ready for use. For example, the SSH server will be reachable from the outside world.

You can browse the web by using the retawq web browser. Use the g key to enter a URL, then navigate around using the cursor and return keys. You can leave the browser by pressing Shift-Q.

If you use ISDN, you can enable and disable channel bundling by calling the bundle and unbundle scripts while the connection is up. The default for new connections is to always use a single channel, even if channel bundling was enabled before. To check whether channel bundling is currently enabled, use the command:

	service isdn status

If you decide that you want to cut the Internet link, just issue:

	ppp-down

This will take the connection down. Once again, this can be done by root or a user from the ppp group, in this case only the user who started the connection.

If you change any of the settings in /etc/isp.conf, you need to update the PPP configuration files by running the following command:

	ppprestart

Note that if you want to switch from using a modem to using ISDN or vice versa, you need to take down the Internet connection before running ppprestart.

After that, you can again use ppp-up and ppp-down. Note that running ppprestart only works for root, not ordinary users. In previous ttylinux versions (2.5 and older), rebooting also updated the PPP configuration files. This is no longer the case to allow manual modifications of the files. They will only be created on boot if they don't exist.

Users in the ppp group will be able to read the file /etc/isp.conf which contains your dialup password. This may or may not be a good idea, depending on how much you trust your users. If you only wish to use ISDN, you can remove the group read permission with

	chmod g-r /etc/isp.conf