On Fri, 8 Oct 2004 16:39:21 +0200 (CEST), Peter Funk <[EMAIL PROTECTED]> wrote: > > So, I'd really be interested in hearing if there is a good solution. > > I'm convinced that it can be done! > > The trick is to have two routes with different Metric. If for example > ippp0 is your ISDN-device and ppp0 is your DSL connection, you could > have two default routes: one with metric == 0 on ppp0 and another one > with metric == 1 on ippp0. If both pppd-Demons are configured to > "dial" on demand, the ISDN connection will be established automatically, > if the pppoed dies for some reason.
OK, sounds reasonable. Can this scheme be adapted to a scenario where 1 NIC (no pppd) and 1 ISDN-card are involved? Putting up-/down-statements into the NIC-setup won't do much good, as the NIC-link doesn't go down, even when the connection on the WAN-side is lost. > Since my setup is little bit different (ISDN goes directly to a computer > in our company network and is a fallback for the VPN) I can't provide > a working configuration file. > Just a guess: you have to insert or modify some 'up' and 'down' commands > in your /etc/network/interfaces file. Like so > ... > iface ppp0 inet ... # DSL (pppoed) > ... > up route add default gw XXX.XXX.XXX.XXX metric 0 > down route del default gw XXX.XXX.XXX.XXX > ... > iface ippp0 inet ... # ISDN > ... > up route add default gw XXX.XXX.XXX.XXX metric 1 > down route del default gw XXX.XXX.XXX.XXX > > Read /usr/share/doc/ifupdown/examples/network-interfaces.gz > for more information. Is there a way to alter the metric of an interface based on RTT of the ISP-router on the other side of the link? I guess this would solve part of the problem.... Best regards, Albert.
