Border Gateway Protocol- FAQ (Broadcom SoNiC)

Border Gateway Protocol- FAQ (Broadcom SoNiC)

 

1. How do I configure BGP hold and keepalive timers? 
Use timers <keepalive> <hold>. 

 

2. How do I enable BGP in SONiC? 

Use router bgp <AS_number> to enter BGP configuration mode. 

 

3. What does neighbor mean in BGP configuration? 
neighbor defines the IP address of the remote peer with whom BGP will establish a connection. 

 

4.How do I specify a remote AS for a BGP neighbor? 
Use neighbor <IP> and then remote-as <AS_number> to configure the remote AS. 

 

5.What is the purpose of update-source in BGP? 
update-source <ip> sets the source IP address for BGP updates to the neighbor. 

 

6. How do I create a BGP peer group? 
Use peer-group <name> in BGP configuration mode. 
 

7. How can I view BGP sessions in SONiC? 
 use show bgp ipv4 unicast summary to display BGP session information. 
 

 

8. How do I enable logging of BGP adjacency changes? 
Use log-neighbor-changes to log BGP neighbor events. 
 

 

9.What command advertises only the best path to each AS? 
Use addpath-tx-bestpath-per-as to advertise the best path per AS. 

 

10.How do I set a description for a BGP neighbor? 
Use neighbor <IP>  and then description <text> to set a description for the neighbor. 
 

11. What is maximum-paths in BGP? 
maximum-paths <paths> sets the number of paths for load balancing. 
 

 

12. How do I configure a route reflector in BGP? 
Use route-reflector-client for a route reflector client configuration. 

             

              13. How do I activate a specific address family for a BGP peer? 
               Use address-family <type> (e.g., ipv4 unicast) in neighbor configuration mode. 
 

 

14. What is as-path filtering in BGP? 
as-path filtering allows specific AS paths to be permitted or denied. 

 

15. How do I reset BGP connections for a neighbor? 
Use clear bgp <IP> to reset a specific BGP session. 

 

16. How do I advertise a network in BGP? 
Use network <IP_address> / <subnet_mask> to advertise a network. 
 

17. What does aggregate-address do in BGP? 
It summarizes routes, reducing the number of advertised routes. 

 

18. How do I configure a BGP community list? 
Use bgp community-list followed by permit or deny rules. 

 

19. What is next-hop-self used for in BGP? 
next-hop-self sets the local router's IP as the next hop for the neighbor. 

 

20. which command enables enforcement first as number for bgp neighbour? 
Use enforce-first-as. 
 

               21. How do I limit the number of prefixes that BGP can learn? 
               Use neighbor <IP> and then maximum-prefix <number>. 

 

22.  What does  allowas-in do? 
It allows BGP to accept updates from its own AS. 

 

23.How do I configure BGP route dampening? 
Use dampening to suppress frequently flapping routes. 

 

24. How do I enable BGP graceful restart? 
Use graceful-restart enable 

 

25. How is a policy map applied to incoming BGP routes? 
Use route-map <name> in. 

 

26. How do I prevent BGP from advertising default routes? 
Use no default-originate. 
 

 

27.  What does soft-reconfiguration inbound do? 
It enables BGP to store received routes for updates without resetting sessions. 
 

 

28.  How do I set a local preference for BGP routes? 
Use set local-preference <value> in a route map. 
 

 

29.How do I enable IPv6 for a BGP neighbor? 
Use address-family ipv6 unicast. 
 

 

30. How can I change the BGP keepalive interval? 
Use timers keepalive <interval>. 

 
 

31.  What does  remove-private-as do? 
This removes private AS numbers from outbound updates to external peers. 
 

 

               32. How can I set a Route-map to selectively unsuppress suppressed routes? 
               Use unsuppress-map. 
                

 

33. How do I set the BGP router ID? 
Use bgp router-id <ID>. 
 

 

34. How can I redistribute static routes into BGP? 
Use redistribute static in BGP configuration. 
 

 

35. How do I configure BGP graceful shutdown? 
Use graceful-shutdown. 
 

 

36. What does activate do in BGP? 
It activates a BGP neighbor under an address family. 
 

 

37. How do I control BGP route advertisements with a route map? 
Use  route-map <map_name> out. 
 

 

38. How do I ignore MED in BGP best path selection? 
Use bestpath med. 
 

 

39. How do I enable all BGP paths to be advertised? 
Use addpath-tx-all-paths. 
 

 

40. How can I view detailed ipv4 BGP information? 
Run show bgp ipv4 unicast neighbors. 
 

 

41. What is local-as in BGP? 
This command specifies an alternate AS for this BGP process when interacting with the specified peers in a peer-group. 
 

 

42. How do I enable BGP dampening ? 
Use dampening parameters in BGP configuration. 
 

 

43. What is route-map in BGP? 
A route-map in BGP controls updates and filters routes based on criteria. 
 

 

44. How does the update-source for BGP? 
This command specifies the IPv4 or IPv6 source address to use for the BGP session to this neighbor. 
 

 

45. How do I apply a filter list to BGP routes? 
Use filter-list <list_name> in|out. 
 

 

46. How can I  allow BGP neighbor to accept as-path with its own AS number present in it.? 
Use bgp allowas-in <value>. 
 

                

   47. How do I Clear peers with address of peer_ip and this address-family activated?  
               Use clear bgp all <A.B.C.D/A::B> 
                 

 

48. What is bgp always-compare-med? 
This setting enables MED comparison between routes from different ASes. 
  

 

49. How can I reset all BGP connections? 
Use clear bgp all to reset all sessions. 
 

50 .How do I create a BGP instance in a VRF on SONiC? 
Use the command router bgp <AS_number> vrf <vrf-name> to create an instance of BGP within a specific VRF. If no VRF is specified, it defaults to the global instance. 
 


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