Final documentation cleanup for updated bridge code.

Specifically document how to handle the case of explicitly starting a
bridge and then dynamically adding interfaces to it.

brctl_br0=''
bridge_add_eth0='br0'

2 files changed, 14 insertions, 9 deletions

diff --git a/doc/net.example.Linux.in b/doc/net.example.Linux.in
index 7955fe3..42e5477 100644
--- a/doc/net.example.Linux.in
+++ b/doc/net.example.Linux.in
@@ -787,11 +787,18 @@
 #bridge_add_eth0="br0"
 #bridge_add_eth1="br0"
 
+# NOTE: If you want to manually start an empty bridge, and then dynamically add
+# ports to it you must set at least one of the following variables based on the
+# interface name, so that we can pick it up from your configuration. Even an
+# empty value variable is fine, but at least one of them must be set:
+# brctl_IFVAR
+
 # You need to configure the ports to null values so dhcp does not get started 
 #config_eth0="null"
 #config_eth1="null"
 
-# Finally give the bridge an address - dhcp or a static IP
+# Finally give the bridge an address - dhcp or a static IP, this is assigned to
+# the bridge when the bridge is explicitly started.
 #config_br0="dhcp" # may not work when adding ports dynamically
 #config_br0="192.168.0.1/24"
 
@@ -812,11 +819,6 @@
 #forward_delay_br0="10"
 #hairpin_mode_eth0="1"
 
-# If you want to start an empty bridge, and then dynmically add ports to it you
-# MUST set the following variables (with the correct interface name).
-# If you get the error "Misconfigured static bridge detected", this means you.
-#bridge_br0=''
-
 #-----------------------------------------------------------------------------
 # RFC 2684 Bridge Support 
 # For RFC 2684 bridge support emerge net-misc/br2684ctl
diff --git a/net/bridge.sh b/net/bridge.sh
index 2f6711e..c0172ed 100644
--- a/net/bridge.sh
+++ b/net/bridge.sh
@@ -32,16 +32,19 @@ _bridge_ports()
 bridge_pre_start()
 {
 	local brif= oiface="${IFACE}" e= x=
+	# ports is for static add
 	local ports="$(_get_array "bridge_${IFVAR}")"
+	# old config options
 	local opts="$(_get_array "brctl_${IFVAR}")"
-	
 	# brif is used for dynamic add
 	eval brif=\$bridge_add_${IFVAR}
-	# ports is for static add
+	
+	# we need a way to if the bridge exists in a variable name, not just the
+	# contents of a variable. Eg if somebody has only bridge_add_eth0='br0',
+	# with no other lines mentioning br0.
 	eval bridge_unset=\${bridge_${IFVAR}-y\}
 	eval brctl_unset=\${brctl_${IFVAR}-y\}
 	
-	# If we are not doing dynamic add on $IFACE, check for static ports.
 	if [ -z "${brif}" -a "${brctl_unset}" == 'y' ]; then
 		if [ -z "${ports}" -a "${bridge_unset}" == "y" ]; then
 			#eerror "Misconfigured static bridge detected (see net.example)"