Hello!  I've been running Shorewall for a few years now, and it's
performed well.

I have a non-trivial setup, though, and it is rough around the edges
when trying to deal with it.  In particular, I have a dual WAN.  One is
cable modem (DHCP), and another is DSL modem (PPPoE).

What's more, the cable modem is a single IP address that often changes,
while the DSL modem is a static IP address *range*.  There is a "main"
address that the PPP connection sets up, but it also accepts several
other nearby addresses.  I have this running right now with aliases for
the ppp0 device.

I've studied this document:

http://shorewall.net/MultiISP.html

There are 3 main problems I have:

1) If the router is rebooted while either the cable or the DSL is down,
Shorewall won't come up  It requires *both* interfaces to be fully 
active before Shorewall will start.  If either is down, my firewall is 
DOA, requiring manual intervention.

I was hoping to set up a dual WAN setup for redundancy and safety, and 
unfortunately instead, this makes it *more* brittle.

2) Shorewall is a one-shot deal: it exists just to configure the
kernel's firewall settings.  There's no active monitor that can stay
around and take care of things if either the cable or the DSL goes down.
  I've written a script that repeatedly pings both the cable and DSL
connection, and attempts to give the command "ip route replace", with
appropriate arguments, as needed.

I'm wondering if there's a more Shorewall-friendly way to do this?  I've 
ran into trouble before, when I mess with the routing table and 
Shorewall doesn't expect this.

3) If the PPP modem goes down, the ppp0 device disappears entirely.
That's unfortunate.  Is there a way to make it behave like the eth* 
devices, where they are allowed be in "down" state and still exist as an
active device within the kernel?

The reason this is a requirement, is that the kernel will drop all 
routing and firewall rules associated with a device, when it disappears! 
  So, if ppp0 disappears, it will later come back up... completely bare, 
as it will have no more firewall or router rules!  I need to manually 
restart Shorewall whenever this happens.

It's really unfortunate that the developers of PPP in Linux chose to
make the device disappear, instead of just keeping it around in a "down"
state.  Because I have a *range* of IP addresses coming to me via PPP, I
can't activate the built-in PPPoE protocol termination feature of the
modem.  If I do this, then the modem takes over the IP addresses, and
only gives me a single IP address from it.

I'm running Shorewall 4.2.10 on Debian.  Is it worth upgrading to 4.4?

What Shorewall output should I provide here, that might assist in asking
for help?

Thanks!

Josh


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