CCNP TSHOOT CHAPTER 9 (BGP)

CCNP TSHOOT CHAPTER 9 (BGP)
17. What are the problems to not form BGP neighbour relationship ?
18. Write down bgp verification commands.

17. What are the problems to not form BGP neighbour relationship ?
Solution:
-->
1. Unreachable next-hop .
2. Wrong AS-number .
3. Wrong neighbour command .
4. Wrong update-source.
5. Wrong use of ebgp-multihop .
6. MD5 authentication .
7. Any filtering device between routers.(like firewall)
commands:
access-list BGPMD5 permit tcp host 2.2.2.2 host 3.3.3.3 eq bgp
access-list BGPMD5 permit tcp host 3.3.3.3 eq bgp host 2.2.2.2
class-map BGPMD5CLASSMAP
match access-list BGPMD5
!
tcp-map BGPMD5OPTION
tcp-options range 19 19 allow
!
policy-map global_policy
class BGPMD5CLASSMAP
set connection random-sequence-number disable
set connection advanced-options BGPMD5OPTION
!

18. Write down bgp verification commands.
-->
sh ip bgp neighbors 3.3.3.3
sh ip bgp
BGP table version is 2, local router ID is 1.1.1.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*> 1.1.1.1/32       0.0.0.0                  0         32768 i

R1#sh ip bgp summary
BGP router identifier 1.1.1.1, local AS number 100
BGP table version is 2, main routing table version 2
1 network entries using 117 bytes of memory
1 path entries using 52 bytes of memory
2/1 BGP path/bestpath attribute entries using 248 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 417 total bytes of memory
BGP activity 1/0 prefixes, 1/0 paths, scan interval 60 secs

Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd
3.3.3.3         4   100       7       8        2    0    0 00:04:21        0
10.1.1.4        4   200       7       8        2    0    0 00:04:39        0