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			60 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			ReStructuredText
		
	
	
	
	
	
| 
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| Routing-policy
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| --------------
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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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| 
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| There could be a wide range of routing policies. Some examples are below:
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| 
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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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| 
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| Routing Policy Example
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| ~~~~~~~~~~~~~~~~~~~~~~
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| 
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| **Policy definition:**
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| 
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| .. code-block:: sh
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| 
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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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|   
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|   #Apply policy to BGP
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|   set protocols bgp 1 neighbor 1.1.1.2 address-family ipv4-unicast route-map import 'setmet'
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|   set protocols bgp 1 neighbor 1.1.1.2 address-family ipv4-unicast soft-reconfiguration 'inbound' <<<< *** 
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|   
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|   *** get policy update without bouncing the neighbor
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| 
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| **Routes learned before routing policy applied:**
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| 
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| .. code-block:: sh
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| 
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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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|   
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|      Network          Next Hop            Metric LocPrf Weight Path
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|   *> 22.22.22.22/32   1.1.1.2                  1             0 2 i  < Path 
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|   
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|   Total number of prefixes 1
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| 
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| **Routes learned after routing policy applied:**
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| 
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| .. code-block:: sh
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| 
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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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|   
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|      Network          Next Hop            Metric LocPrf Weight Path
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|   *> 22.22.22.22/32   1.1.1.2                  1             0 2 2 2 2 i < longer AS_path length
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|   
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|   Total number of prefixes 1
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|   vyos@vos1:~$ 
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