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61 lines
2.1 KiB
ReStructuredText
61 lines
2.1 KiB
ReStructuredText
.. include:: ../_include/need_improvement.txt
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Routing-policy
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--------------
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Routing Policies could be used to tell the router (self or neighbors) what routes and their attributes needs to be put into the routing table.
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There could be a wide range of routing policies. Some examples are below:
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* Set some metric to routes learned from a particular neighbor
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* Set some attributes (like AS PATH or Community value) to advertised routes to neighbors
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* Prefer a specific routing protocol routes over another routing protocol running on the same router
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Routing Policy Example
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~~~~~~~~~~~~~~~~~~~~~~
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**Policy definition:**
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.. code-block:: none
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#Create policy
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set policy route-map setmet rule 2 action 'permit'
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set policy route-map setmet rule 2 set as-path-prepend '2 2 2'
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#Apply policy to BGP
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set protocols bgp 1 neighbor 203.0.113.2 address-family ipv4-unicast route-map import 'setmet'
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set protocols bgp 1 neighbor 203.0.113.2 address-family ipv4-unicast soft-reconfiguration 'inbound' <<<< ***
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*** get policy update without bouncing the neighbor
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**Routes learned before routing policy applied:**
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.. code-block:: none
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vyos@vos1:~$ show ip bgp
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BGP table version is 0, local router ID is 192.168.56.101
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Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
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r RIB-failure, S Stale, R Removed
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Origin codes: i - IGP, e - EGP, ? - incomplete
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Network Next Hop Metric LocPrf Weight Path
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*> 198.51.100.3/32 203.0.113.2 1 0 2 i < Path
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Total number of prefixes 1
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**Routes learned after routing policy applied:**
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.. code-block:: none
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vyos@vos1:~$ sho ip b
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BGP table version is 0, local router ID is 192.168.56.101
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Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
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r RIB-failure, S Stale, R Removed
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Origin codes: i - IGP, e - EGP, ? - incomplete
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Network Next Hop Metric LocPrf Weight Path
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*> 198.51.100.3/32 203.0.113.2 1 0 2 2 2 2 i < longer AS_path length
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Total number of prefixes 1
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vyos@vos1:~$
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