Question 2mediummultiple choice
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A network engineer runs the following command on Router R1:
R1# show bgp summary
BGP router identifier 10.1.1.1, local AS number 65001 BGP table version is 15, main routing table version 15 2 network entries using 288 bytes of memory 2 path entries using 160 bytes of memory 2/1 BGP path/bestpath attribute entries using 288 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 736 total bytes of memory BGP activity 4/2 prefixes, 4/2 paths, scan interval 60 secs
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd 10.1.12.2 4 65002 1023 1047 15 0 0 00:12:34 0 192.168.1.2 4 65003 0 0 0 0 0 never Active
Based on this output, what is the problem with the BGP session to 192.168.1.2?
A network engineer runs the following command on Router R1:
R1# show bgp ipv4 unicast 10.1.1.0/24
BGP routing table entry for 10.1.1.0/24, version 2 Paths: (1 available, best #1, table default) Advertised to update-groups: 1 Refresh Epoch 1 Local
10.1.1.1 from 0.0.0.0 (10.1.1.1)
Origin IGP, metric 0, localpref 100, weight 32768, valid, sourced, best rx pathid: 0, tx pathid: 0x0
Based on this output, which statement is correct?
A network engineer runs the following command on Router R1:
R1# show ip bgp neighbors 10.1.12.2
BGP neighbor is 10.1.12.2, remote AS 65002, external link BGP version 4, remote router ID 10.2.2.2 BGP state = Idle Last read 00:00:00, last write 00:00:00, hold time is 180, keepalive interval is 60 seconds
Neighbor sessions:
1 active, is not multisession capable (disabled)
Neighbor capabilities:
Route refresh: advertised and received(new) Four-octets ASN Capability: advertised and received Address family IPv4 Unicast: advertised and received Enhanced Refresh Capability: advertised Multisession Capability: State is never active Message statistics: InQ depth is 0 OutQ depth is 0
Based on this output, what is the most likely cause of the BGP session being in Idle state?
A network engineer runs the following command on Router R1:
R1# show bgp ipv4 unicast 10.2.2.0/24
BGP routing table entry for 10.2.2.0/24, version 5 Paths: (1 available, best #1, table default) Not advertised to any peer Refresh Epoch 1 65002
10.1.12.2 from 10.1.12.2 (10.2.2.2)
Origin IGP, metric 0, localpref 100, valid, external, best rx pathid: 0, tx pathid: 0x0
Based on this output, what is a potential issue with this route?
A network engineer runs the following command on Router R1:
R1# show bgp ipv4 unicast 10.3.3.0/24
BGP routing table entry for 10.3.3.0/24, version 10 Paths: (2 available, best #2, table default) Advertised to update-groups: 1 Refresh Epoch 1 65003 65004
10.1.13.3 from 10.1.13.3 (10.3.3.3)
Origin IGP, metric 0, localpref 100, valid, external rx pathid: 0, tx pathid: 0 Refresh Epoch 1 65005
10.1.15.5 from 10.1.15.5 (10.5.5.5)
Origin IGP, metric 0, localpref 200, valid, external, best rx pathid: 0, tx pathid: 0x0
Based on this output, why is the path via 10.1.15.5 chosen as best?
A network engineer runs the following command on Router R1:
R1# show bgp neighbors 10.1.12.2 advertised-routes
BGP table version is 15, local router ID is 10.1.1.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path *> 10.1.1.0/24 0.0.0.0 0 32768 i *> 10.2.2.0/24 10.1.12.2 0 0 65002 i
Total number of prefixes 2
Based on this output, what can be concluded about the route 10.2.2.0/24?
A network engineer runs the following command on Router R1:
R1# show bgp ipv4 unicast 10.4.4.0/24
BGP routing table entry for 10.4.4.0/24, version 8 Paths: (1 available, best #1, table default) Not advertised to any peer Refresh Epoch 1 65006
10.1.16.6 from 10.1.16.6 (10.6.6.6)
Origin IGP, metric 0, localpref 100, valid, external, best rx pathid: 0, tx pathid: 0x0
Based on this output, what is the most likely reason the route is not advertised to any peer?
A network engineer runs the following command on Router R1:
R1# show bgp neighbors 10.1.12.2 received-routes
BGP table version is 15, local router ID is 10.1.1.1 Status codes: s suppressed, d damped, h history, * valid, > best, i - internal, r RIB-failure, S Stale, m multipath, b backup-path, f RT-Filter, x best-external, a additional-path, c RIB-compressed, Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path *> 10.2.2.0/24 10.1.12.2 0 0 65002 i
Total number of prefixes 1
Based on this output, what can be inferred about the BGP session?
A network engineer runs the following command on Router R1:
R1# show bgp ipv4 unicast 10.5.5.0/24
BGP routing table entry for 10.5.5.0/24, version 12 Paths: (1 available, best #1, table default) Advertised to update-groups: 1 Refresh Epoch 1 65007
10.1.17.7 from 10.1.17.7 (10.7.7.7)
Origin IGP, metric 0, localpref 100, valid, external, best rx pathid: 0, tx pathid: 0x0
Based on this output, what does the 'r' in the status codes indicate if present? (Not shown here, but the engineer notices a similar route with 'r' status.)
Given the following BGP configuration on router R1:
router bgp 65001
bgp router-id 1.1.1.1
neighbor 10.1.1.2 remote-as 65002 neighbor 10.1.1.2 route-map SET-MED out
! route-map SET-MED permit 10 match ip address prefix-list LOOPBACKS set metric 100 ! route-map SET-MED permit 20 !
ip prefix-list LOOPBACKS permit 192.168.0.0/24
What is the effect of this configuration?
Consider the following BGP configuration on router R2:
router bgp 65002
bgp router-id 2.2.2.2
neighbor 10.2.2.1 remote-as 65001 neighbor 10.2.2.1 route-map FILTER in
! route-map FILTER deny 10 match ip address prefix-list BLOCKED ! route-map FILTER permit 20 !
ip prefix-list BLOCKED permit 10.0.0.0/8 le 32
Which statement is true about routes received from 10.2.2.1?
Examine this BGP configuration on router R3:
router bgp 65003
bgp router-id 3.3.3.3
neighbor 10.3.3.2 remote-as 65002 neighbor 10.3.3.2 ebgp-multihop 2 neighbor 10.3.3.2 update-source Loopback0
!
interface Loopback0 ip address 3.3.3.3 255.255.255.255
What is the likely issue with this configuration?
A network engineer configures BGP on router R4:
router bgp 65004
bgp router-id 4.4.4.4
neighbor 10.4.4.3 remote-as 65003 neighbor 10.4.4.3 password BGPsecret
!
What is the effect of the password command?
Consider the following BGP configuration on router R5:
router bgp 65005
bgp router-id 5.5.5.5
neighbor 10.5.5.6 remote-as 65006 neighbor 10.5.5.6 route-map SET-LP in
! route-map SET-LP permit 10 set local-preference 150 !
What is the result of this configuration?
Examine this BGP configuration on router R6:
router bgp 65006
bgp router-id 6.6.6.6
neighbor 10.6.6.7 remote-as 65007 neighbor 10.6.6.7 weight 200
!
What is the effect of the weight command?
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