It may seem like cheating, but instead of doing it all in squid maybe:
Set the parent you want to use whenever available to pick up all
traffic transparently.
Set the one you want to switch to have no parents or peers.
Simply moniter the line with a script and ping (or something more
classy that opens a http request to the proxy) and when it fails, swap the
default route over. When it comes back, swap the route back over. With
ping you could conceivably have a resolution of 3 or so seconds before
failing over.
Or instead of a script, you could run a routing protocol and set the
priority to the link you would prefer to use.
Just a thought,
David Nillesen
Northnet Internet Services
+612 67749300
Type Bits/KeyID Date User ID
pub 2048/BBCA4E3D 1998/01/03 David A Nillesen <dave@northnet.com.au>
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Received on Fri Dec 03 1999 - 05:59:26 MST
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