[Sussex] Persistent routes

[Steve Dobson]

Hi Simon

On 15/05/12 12:33, Simon Story wrote:
> On 15/05/12 11:43, Paul Howard wrote:
> You can't specify 'gateway' twice in an debian/ubuntu interfaces file,
> that is shorthand for setting the default route. You can only have one
> default route.

Why can you have only one default route?

As far as I am aware the default route is nothing special (in routing
terms) other than it matches all addresses so it needs to be the last
route tried by the routing software.  Therefore, a site with two ISP
links would have two default routes and a packet could be routed via
either to get off the site.  Useful if one of the links should go down
or (more likely) become very busy.

True, most sites (esp homes) only have one ISP link.  In this case then
there can be only one default route.  But while this may be the most
common configuration I don't think it is a requirement.

> Remove the gateway line one eth1:0 and see what happens.

The problem is not the gateway line, I believe it to be the fact that
the host and the gateway do not share a common network address and thus
the routing tables can't figure out how to route packets to the other
network.

Steve
-- 
Steve "Dobbo" Dobson