Added description of Static, Device and Direct protocols.

This commit is contained in:
Martin Mares 2000-05-29 11:30:25 +00:00
parent 98627595fb
commit 79a2b697e3

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@ -402,8 +402,75 @@ if 1234 = i then printn "."; else { print "*** FAIL: if 1 else"; }
<sect1>Device <sect1>Device
<sect2>Introduction
<p>The Device protocol is not a real routing protocol as it doesn't generate
any routes and only serves as a module for getting information about network
interfaces from the kernel.
<p>Except for very unusual circumstances, you probably should always include
this protocol in the configuration since almost all other protocol don't
do anything if they are not provided with network interfaces.
<sect2>Configuration
<p><descrip>
<tag>scan time <m/number/</tag> Time in seconds between two scans
of the network interface list. On systems where we are notified about
interface status changes asynchronously (such as newer versions of
Linux), we need to scan the list only to avoid confusion by lost
notifications, so the default time is set to a large value.
</descrip>
<sect2>Attributes
<p>As the Device protocol doesn't generate any routes, it cannot have
any attributes.
<sect2>Example
<p><code>
protocol device {
scan time 10; # Scan the interfaces often
}
</code>
<sect1>Direct <sect1>Direct
<sect2>Introduction
<p>The Direct protocol is a simple generator of device routes for all the
directly connected networks according to the list of interfaces provided
by the kernel via the Device protocol.
<p>It's highly recommended to include this protocol in your configuration
unless you want to use BIRD as a route server or a route reflector, that is
on a machine which doesn't forward packets and only participates in
distribution of routing information.
<sect2>Configuration
<p><descrip>
<tag>interface <m/pattern/, <m/.../</tag> By default, the Direct
protocol will generate device routes for all the interfaces
available. If you want to restrict it to some subset of interfaces
(for example if you're using multiple routing tables for policy
routing and some of the policy domains don't contain all interfaces),
just use this clause.
</descrip>
<sect2>Attributes
<p>Direct device routes don't contain any specific attributes.
<sect2>Example
<p><code>
protocol direct {
interface "-arc*", "*"; # Exclude the ARCnets
}
</code>
<sect1>Kernel <sect1>Kernel
<sect1>OSPF <sect1>OSPF
@ -506,6 +573,58 @@ protocol rip MyRIP_test {
<sect1>Static <sect1>Static
<sect2>Introduction
<p>The static protocol doesn't communicate with other routers in the network,
but instead it allows you to define routes manually which is often used for
specifying how to forward packets to parts of the network which don't use
dynamic routing at all and also for defining sink routes (i.e., those
telling to return packets as undeliverable if they are in your IP block,
you don't have any specific destination for them and you don't want to send
them out through the default route to prevent routing loops).
<p>There are three types of static routes: `classical' routes telling to
forward packets to a neighboring router, device routes specifying forwarding
to hosts on a directly connected network and special routes (sink, blackhole
etc.) which specify a special action to be done instead of forwarding the
packet.
<p>When the particular destination is not available (the interface is down or
the next hop of the route is not a neighbor at the moment), Static just
uninstalls the route from the table its connected to and adds it again as soon
as the destinations becomes adjacent again.
<sect2>Configuration
<p>The Static protocol has no configuration options. Instead, the
definition of the protocol contains a list of static routes which
can contain:
<descrip>
<tag>route <m/prefix/ via <m/ip/</tag> Static route through
a neighboring router.
<tag>route <m/prefix/ via <m/"interface"/</tag> Static device
route through an interface to hosts on a directly connected network.
<tag>route <m/prefix/ drop|reject|prohibit</tag> Special routes
specifying to drop the packet, return it as unreachable or return
it as administratively prohibited.
</descrip>
<sect2>Attributes
<p>Static routes have no specific attributes.
<sect2>Example
<p><code>
protocol static {
table testable; # Connect to non-default routing table
route 0.0.0.0/0 via 62.168.0.13; # Default route
route 62.168.0.0/25 reject; # Sink route
route 10.2.0.0/24 via "arc0"; # Secondary network
}
</code>
<sect>Getting more help <sect>Getting more help
<p>This is really last section of this file, should give pointers to <p>This is really last section of this file, should give pointers to