Merge pull request #418 from craterman/patch-4

Update ospf.rst
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@ -19,20 +19,90 @@ OSPF is a widely used IGP in large enterprise networks.
OSPFv2 (IPv4) OSPFv2 (IPv4)
############# #############
In order to have a VyOS system exchanging routes with OSPF neighbors, you will .. cfgcmd:: set protocols ospf area <number>
at least need to configure an OSPF area and some network.
.. code-block:: none This command is udes to enable the OSPF process. The area number can be
specified in decimal notation in the range from 0 to 4294967295. Or it
can be specified in dotted decimal notation similar to ip address.
set protocols ospf area 0 network 192.168.0.0/24 .. cfgcmd:: set protocols ospf area <number> network <A.B.C.D/M>
That is the minimum configuration you will need. This command specifies the OSPF enabled interface(s). If the interface has
It is a good practice to define the router ID too. an address from defined range then the command enables OSPF on this
interface so router can provide network information to the other ospf
routers via this interface.
.. code-block:: none .. cfgcmd:: set protocols ospf auto-cost reference-bandwidth <number>
set protocols ospf parameters router-id 10.1.1.1 This command sets the reference bandwidth for cost calculations, where
bandwidth can be in range from 1 to 4294967, specified in Mbits/s. The
default is 100Mbit/s (i.e. a link of bandwidth 100Mbit/s or higher will
have a cost of 1. Cost of lower bandwidth links will be scaled with
reference to this cost).
.. cfgcmd:: set protocols ospf default-information originate [always] [metric <number>] [metric-type <1|2>] [route-map <name>]
Originate an AS-External (type-5) LSA describing a default route into all
external-routing capable areas, of the specified metric and metric type.
If the :cfgcmd:`always` keyword is given then the default is always advertised,
even when there is no default present in the routing table. The argument
:cfgcmd:`route-map` specifies to advertise the default route if the route map
is satisfied.
.. cfgcmd:: set protocols ospf default-metric <number>
This command specifies the default metric value of redistributed routes.
The metric range is 0 to 16777214.
.. cfgcmd:: set protocols ospf distance global <distance>
This command change distance value of OSPF. The distance range is 1 to 255.
.. cfgcmd:: set protocols ospf distance ospf <external|inter-area|intra-area> <distance>
This command change distance value of OSPF. The arguments are the distance
values for external routes, inter-area routes and intra-area routes
respectively. The distance range is 1 to 255.
.. note:: Routes with a distance of 255 are effectively disabled and not
installed into the kernel.
.. cfgcmd:: set protocols ospf parameters router-id <rid>
This command sets the router-ID of the OSPF process. The router-ID may be an
IP address of the router, but need not be - it can be any arbitrary 32bit number.
However it MUST be unique within the entire OSPF domain to the OSPF speaker bad
things will happen if multiple OSPF speakers are configured with the same router-ID!
.. cfgcmd:: set protocols ospf parameters rfc1583-compatibility
:rfc:`2328`, the successor to :rfc:`1583`, suggests according to section G.2 (changes)
in section 16.4.1 a change to the path preference algorithm that prevents possible
routing loops that were possible in the old version of OSPFv2. More specifically it
demands that inter-area paths and intra-area backbone path are now of equal preference
but still both preferred to external paths.
This command should NOT be set normally.
.. cfgcmd:: set protocols ospf passive-interface <interface>
This command specifies interface as passive. Passive interface advertises its address,
but does not run the OSPF protocol (adjacencies are not formed and hello packets are
not generated).
.. cfgcmd:: set protocols ospf passive-interface default
This command specifies all interfaces as passive by default. Because this command changes
the configuration logic to a default passive; therefore, interfaces where router adjacencies
are expected need to be configured with the :cfgcmd:`passive-interface-exclude` command.
.. cfgcmd:: set protocols ospf passive-interface-exclude <interface>
This command allows exclude interface from passive state. This command is used if the
command :cfgcmd:`passive-interface default` was configured.
Configuration example
---------------------
Below you can see a typical configuration using 2 nodes, redistribute loopback Below you can see a typical configuration using 2 nodes, redistribute loopback
address and the node 1 sending the default route: address and the node 1 sending the default route: