I've been trying to address ticket 3053 and want to step back and 
discuss the requirements for the scripts.   The discussion actually 
crosses into blfs as well as lfs due to dhcp and bridge issues, but I 
want to discuss all of them here at a relatively high level.

Networking starts off with the network script.  It basically calls 
/sbin/ifup (or ifdown) for each file in /etc/sysconfig/ifconfig.*

The ifup script does:
   if not inhibited, 'ip link set ${IFACE} up'
   if MTU is requested, 'ip link set dev ${IFACE} mtu $MTU'
   for S in ${SERVICE}; do run the script

   SERVICE can be ipv4-static, ipv4-static-route, (and in blfs) bridge,
   dhclient, or dhcpcd.

Where it gets complicated is in bridge where it is a compound interface 
that can contain (an)other interface(s), most likely eth0.  The only 
reason I introduced the bridge script was to support a virtual computer 
such as KVM.  I'm not aware of any other common uses for a bridge 
interface. (Normally a bridge is used to convert between different 
protocols at the link layer, but we use it to connect multiple ethx 
interfaces more like a switch than a bridge.)

The host that creates the bridge would normally have a single physical 
interface, eth0, and I'd think that would normally be configured with a 
static IP address.  Virtual hosts then connect to the bridge 
dynamically.  If a dhcp address is used, then the connections could only 
be outgoing unless you rube-goldberg something that dynamically sets up 
a dns server.

The question here is whether we need to support automatic setup of a 
bridge with an arbitrary number of interfaces, eth0, eth1, ... ethn.
Making the boot scripts handle a bridge with a single ethx interface is 
not too bad, but it gets fairly complicated when multiple interfaces are 
specified.

My feeling is that we should not try to provide every possible option 
like a commercial distro, but instead provide relatively simple and 
readable scripts that are usable for the majority of LFS users and let 
those few users that want/need something more complex use custom scripts 
that address their requirements.

Discussion?

   -- Bruce
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