babeld: Update example configuration file

More example filters are provided, and new options such as "type" or
"pref_src" are given as example.

Signed-off-by: Baptiste Jonglez <git@bitsofnetworks.org>

diff --git a/babeld/files/babeld.config b/babeld/files/babeld.config
index 0073f73f5667a49137a49fb48eb7f0edcde94a38..a02f2023bdd0a12ac82507696dbcf157fe3a6750 100644 (file)
--- a/babeld/files/babeld.config
+++ b/babeld/files/babeld.config
@@ -1,5 +1,7 @@
 package babeld
 
+# Detailed documentation: https://openwrt.org/docs/guide-user/services/babeld
+
 # Babeld reads options from the following files (the last one takes precedence
 # if an option is defined in several places):
 # - the file defined by the option conf_file (default: /etc/babeld.conf),
@@ -39,7 +41,10 @@ config interface
        option 'ignore' 'true'
        ## Physical interface name
        option 'ifname' 'tun-example'
-       # option 'max_rtt_penalty' '90'
+        ## Specify the type of interface: tunnels use the RTT-based metric.
+       option 'type' 'tunnel'
+       ## Other options that can be overriden.
+       # option 'max_rtt_penalty' '96'
 
 # A config interface without "option ifname" will set default options
 # for all interfaces.  Interface-specific configuration always overrides
@@ -49,27 +54,49 @@ config interface
        # option 'update_interval' '30'
 
 
-# A filter consists of a type ('in', 'out' or 'redistribute'), an action
-# ('allow', 'deny' or 'metric xxx') and a set of selectors ('ip', 'eq',
-# etc.).  See babeld man page ("Filtering rules") for more details.
-# Here is a sample filter wich redistributes the default route if its
-# protocol number is "boot", e.g. when it installed by dhcp.  It is
-# disabled by default.
+# A filter consists of a type ('in', 'out', 'redistribute' or 'install'),
+# a set of selectors ('ip', 'eq', etc.) and a set of actions to perform
+# ('allow', 'deny', 'metric xxx', 'src-prefix xxx', 'table xxx', 'pref-src xxx').
+# See babeld man page ("Filtering rules") for more details.
+
+# Below is a sample filter that redistributes the default route if its
+# protocol number is "boot", e.g. when it is installed by dhcp (see
+# /etc/iproute2/rt_protos).  This filter is disabled thanks to the 'ignore'
+# setting.
 config filter
        option 'ignore' 'true'
-       # Type
+       # Type of filter
        option 'type'   'redistribute'
        # Selectors: ip, eq, le, ge, src_ip, src_eq, src_le, src_ge, neigh, id,
        # proto, local, if.
        option 'ip'     '0.0.0.0/0'
        option 'eq'     '0'
        option 'proto'  '3'
-       # Action (one of: allow, deny, metric XXX, src-prefix XXX).
+       # Action, which can be any of: allow, deny, metric <NUMBER>, src-prefix <PREFIX>,
+       # table <ID>, pref-src <IP>.
+       # The action defaults to "allow" if not specified.  Here, we specify a higher
+       # redistribution metric than the default (0).
        option 'action' 'metric 128'
 
-# Notice that the 'local' selector is a boolean.
+# Another example filter: don't redistribute local addresses in a certain IP prefix.
+# By default, babeld redistributes *all* local addresses.
 config filter
        option 'ignore' 'true'
        option 'type'   'redistribute'
+       # Only apply to routes/addresses within this prefix.
+       option 'ip'     '198.51.100.0/24'
+       # Notice that the 'local' selector is a boolean.
        option 'local'  'true'
-       # No action means "allow"
+       # Don't redistribute.
+       option 'action' 'deny'
+
+# Example install filter, to change or filter routes before they are inserted
+# into the kernel.
+config filter
+       option 'ignore'         'true'
+       option 'type'           'install'
+       # Optional: only apply to routes within 2001:db8:cafe::/48
+       option 'ip'             '2001:db8:cafe::/48'
+       # We specify the kernel routing table and the preferred source address to use for these routes.
+       # "Allow" is implicit.
+       option 'action'         'table 200  pref-src 2001:db8:ba:be1::42'