summaryrefslogtreecommitdiff
path: root/docs/routing/bgp.rst
blob: 6a2ce581f4d7cc6b60cdfe5b0b61d447051930fc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
.. _bgp:

BGP
---

:abbr:`BGP (Border Gateway Protocol) is one of the Exterior Gateway Protocols
and the de facto standard interdomain routing protocol. The latest BGP version
is 4. BGP-4 is described in :rfc:`1771` and updated by :rfc:`4271`. :rfc:`2858`
adds multiprotocol support to BGP.

IPv4
^^^^

A simple eBGP configuration:

**Node 1:**

.. code-block:: console

  set protocols bgp 65534 neighbor 192.168.0.2 ebgp-multihop '2'
  set protocols bgp 65534 neighbor 192.168.0.2 remote-as '65535'
  set protocols bgp 65534 neighbor 192.168.0.2 update-source '192.168.0.1'
  set protocols bgp 65534 address-family ipv4-unicast network '172.16.0.0/16'
  set protocols bgp 65534 parameters router-id '192.168.0.1'

**Node 2:**

.. code-block:: console

  set protocols bgp 65535 neighbor 192.168.0.1 ebgp-multihop '2'
  set protocols bgp 65535 neighbor 192.168.0.1 remote-as '65534'
  set protocols bgp 65535 neighbor 192.168.0.1 update-source '192.168.0.2'
  set protocols bgp 65535 address-family ipv4-unicast network '172.17.0.0/16'
  set protocols bgp 65535 parameters router-id '192.168.0.2'


Don't forget, the CIDR declared in the network statement MUST **exist in your
routing table (dynamic or static), the best way to make sure that is true is
creating a static route:**

**Node 1:**

.. code-block:: console

  set protocols static route 172.16.0.0/16 blackhole distance '254'

**Node 2:**

.. code-block:: console

  set protocols static route 172.17.0.0/16 blackhole distance '254'


IPv6
^^^^

A simple BGP configuration via IPv6.

**Node 1:**

.. code-block:: console

  set protocols bgp 65534 neighbor 2001:db8::2 ebgp-multihop '2'
  set protocols bgp 65534 neighbor 2001:db8::2 remote-as '65535'
  set protocols bgp 65534 neighbor 2001:db8::2 update-source '2001:db8::1'
  set protocols bgp 65534 neighbor 2001:db8::2 address-family ipv6-unicast
  set protocols bgp 65534 address-family ipv6-unicast network '2001:db8:1::/48'
  set protocols bgp 65534 parameters router-id '10.1.1.1'

**Node 2:**

.. code-block:: console

  set protocols bgp 65535 neighbor 2001:db8::1 ebgp-multihop '2'
  set protocols bgp 65535 neighbor 2001:db8::1 remote-as '65534'
  set protocols bgp 65535 neighbor 2001:db8::1 update-source '2001:db8::2'
  set protocols bgp 65535 neighbor 2001:db8::1 address-family ipv6-unicast
  set protocols bgp 65535 address-family ipv6-unicast network '2001:db8:2::/48'
  set protocols bgp 65535 parameters router-id '10.1.1.2'

Don't forget, the CIDR declared in the network statement **MUST exist in your
routing table (dynamic or static), the best way to make sure that is true is
creating a static route:**

**Node 1:**

.. code-block:: console

  set protocols static route6 2001:db8:1::/48 blackhole distance '254'

**Node 2:**

.. code-block:: console

  set protocols static route6 2001:db8:2::/48 blackhole distance '254'

Route Filter
^^^^^^^^^^^^

Route filter can be applied using a route-map:

**Node1:**

.. code-block:: console

  set policy prefix-list AS65535-IN rule 10 action 'permit'
  set policy prefix-list AS65535-IN rule 10 prefix '172.16.0.0/16'
  set policy prefix-list AS65535-OUT rule 10 action 'deny'
  set policy prefix-list AS65535-OUT rule 10 prefix '172.16.0.0/16'
  set policy prefix-list6 AS65535-IN rule 10 action 'permit'
  set policy prefix-list6 AS65535-IN rule 10 prefix '2001:db8:2::/48'
  set policy prefix-list6 AS65535-OUT rule 10 action 'deny'
  set policy prefix-list6 AS65535-OUT rule 10 prefix '2001:db8:2::/48'
  set policy route-map AS65535-IN rule 10 action 'permit'
  set policy route-map AS65535-IN rule 10 match ip address prefix-list 'AS65535-IN'
  set policy route-map AS65535-IN rule 10 match ipv6 address prefix-list 'AS65535-IN'
  set policy route-map AS65535-IN rule 20 action 'deny'
  set policy route-map AS65535-OUT rule 10 action 'deny'
  set policy route-map AS65535-OUT rule 10 match ip address prefix-list 'AS65535-OUT'
  set policy route-map AS65535-OUT rule 10 match ipv6 address prefix-list 'AS65535-OUT'
  set policy route-map AS65535-OUT rule 20 action 'permit'
  set protocols bgp 65534 neighbor 2001:db8::2 route-map export 'AS65535-OUT'
  set protocols bgp 65534 neighbor 2001:db8::2 route-map import 'AS65535-IN'

**Node2:**

.. code-block:: console

  set policy prefix-list AS65534-IN rule 10 action 'permit'
  set policy prefix-list AS65534-IN rule 10 prefix '172.17.0.0/16'
  set policy prefix-list AS65534-OUT rule 10 action 'deny'
  set policy prefix-list AS65534-OUT rule 10 prefix '172.17.0.0/16'
  set policy prefix-list6 AS65534-IN rule 10 action 'permit'
  set policy prefix-list6 AS65534-IN rule 10 prefix '2001:db8:1::/48'
  set policy prefix-list6 AS65534-OUT rule 10 action 'deny'
  set policy prefix-list6 AS65534-OUT rule 10 prefix '2001:db8:1::/48'
  set policy route-map AS65534-IN rule 10 action 'permit'
  set policy route-map AS65534-IN rule 10 match ip address prefix-list 'AS65534-IN'
  set policy route-map AS65534-IN rule 10 match ipv6 address prefix-list 'AS65534-IN'
  set policy route-map AS65534-IN rule 20 action 'deny'
  set policy route-map AS65534-OUT rule 10 action 'deny'
  set policy route-map AS65534-OUT rule 10 match ip address prefix-list 'AS65534-OUT'
  set policy route-map AS65534-OUT rule 10 match ipv6 address prefix-list 'AS65534-OUT'
  set policy route-map AS65534-OUT rule 20 action 'permit'
  set protocols bgp 65535 neighbor 2001:db8::1 route-map export 'AS65534-OUT'
  set protocols bgp 65535 neighbor 2001:db8::1 route-map import 'AS65534-IN'

We could expand on this and also deny link local and multicast in the rule 20
action deny.