Bfd

Scenario to verify BGP with BFD (Bidirectional Forwarding Detection) for fast failure detection. BFD provides sub-second detection of link or neighbor failures, allowing BGP to react much faster than using BGP keepalive timers alone (which typically take tens of seconds). This test demonstrates BFD with eBGP multihop sessions where DUT0 and DUT1 are separated by a transit router (DUT2). The test verifies that when BGP traffic is blocked, BFD detects the failure and tears down the BGP session quickly.

Test eBGP with BFD

Description

Test to check eBGP with BFD protocol

Scenario

Step 1: Set the following configuration in DUT1 :

set interfaces dummy dum0 address 1.1.1.1/24
set interfaces ethernet eth0 address 10.10.0.200/24
set protocols bgp 20 neighbor peer bfd
set protocols bgp 20 neighbor peer remote-address 10.10.0.100
set protocols bgp 20 neighbor peer remote-as 10
set protocols bgp 20 neighbor peer route-map export PERMIT
set protocols bgp 20 redistribute connected route-map REDIS
set protocols logging bgp bfd
set protocols logging bgp neighbor-events
set protocols logging level debugging
set protocols route-map PERMIT rule 1 action permit
set protocols route-map REDIS rule 1 action permit
set protocols route-map REDIS rule 1 match interface dum0
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Set the following configuration in DUT0 :

set interfaces ethernet eth0 address 10.10.0.100/24
set protocols bgp 10 neighbor peer bfd
set protocols bgp 10 neighbor peer remote-address 10.10.0.200
set protocols bgp 10 neighbor peer remote-as 20
set protocols bgp 10 neighbor peer route-map import PERMIT
set protocols logging bgp bfd
set protocols logging bgp neighbor-events
set protocols logging level debugging
set protocols route-map PERMIT rule 1 action permit
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'
set traffic policy DROP rule 1 action drop
set traffic policy DROP rule 1 selector DROP
set traffic selector DROP rule 1 destination port 179
set traffic selector DROP rule 1 protocol tcp
set traffic selector DROP rule 2 protocol tcp
set traffic selector DROP rule 2 source port 179
set traffic selector DROP rule 3 destination port 3784
set traffic selector DROP rule 3 protocol udp

Step 3: Run command protocols bgp show ip neighbors at DUT0 and check if output matches the following regular expressions:

BGP state = Established
Status: Up
BFD: Type: single hop
Show output
BGP neighbor is 10.10.0.200, remote AS 20, local AS 10, external link
  Local Role: undefined
  Remote Role: undefined
Hostname: osdx
  BGP version 4, remote router ID 10.10.0.200, local router ID 10.10.0.100
  BGP state = Established, up for 00:00:02
  Last read 00:00:01, Last write 00:00:01
  Hold time is 90 seconds, keepalive interval is 30 seconds
  Configured hold time is 90 seconds, keepalive interval is 30 seconds
  Configured tcp-mss is 0, synced tcp-mss is 1448
  Configured conditional advertisements interval is 60 seconds
  Neighbor capabilities:
    4 Byte AS: advertised and received
    AddPath:
      IPv4 Unicast: RX advertised and received
    Paths-Limit:
      IPv4 Unicast: advertised (0) and received (0)
    Long-lived Graceful Restart: advertised and received
      Address families by peer:
    Route refresh: advertised and received
    Enhanced Route Refresh: advertised and received
    Address Family IPv4 Unicast: advertised and received
    Hostname Capability: advertised (name: osdx,domain name: n/a) received (name: osdx,domain name: n/a)
    Version Capability: not advertised not received
    Link-Local Next Hop Capability: not advertised not received
    Graceful Restart Capability: advertised and received
      Remote Restart timer is 120 seconds
      Address families by peer:
        none
  Graceful restart information:
    End-of-RIB send: IPv4 Unicast
    End-of-RIB received: IPv4 Unicast
    Local GR Mode: Helper*
    Remote GR Mode: Helper
    R bit: True
    N bit: True
    Timers:
      Configured Restart Time(sec): 120
      Received Restart Time(sec): 120
      Configured LLGR Stale Path Time(sec): 0
    IPv4 Unicast:
      F bit: False
      End-of-RIB sent: Yes
      End-of-RIB sent after update: Yes
      End-of-RIB received: Yes
      Timers:
        Configured Stale Path Time(sec): 360
        LLGR Stale Path Time(sec): 0
  Message statistics:
    Inq depth is 0
    Outq depth is 0
                         Sent       Rcvd
    Opens:                  2          1
    Notifications:          1          0
    Updates:                1          3
    Keepalives:             1          1
    Route Refresh:          1          2
    Capability:             0          0
    Total:                  6          7

  Prefix statistics:
    Inbound filtered: 0
    AS-PATH loop: 0
    Originator loop: 0
    Cluster loop: 0
    Invalid next-hop: 0
    Withdrawn: 0
    Attributes discarded: 0

  Minimum time between advertisement runs is 0 seconds

 For address family: IPv4 Unicast
  Update group 1, subgroup 1
  Packet Queue length 0
  Community attribute sent to this neighbor(all)
  Inbound path policy configured
  Route map for incoming advertisements is *PERMIT
  Outbound updates discarded due to missing policy
  1 accepted, 0 sent prefixes

  Connections established 1; dropped 0
  Last reset never
  External BGP neighbor may be up to 1 hops away.
Local host: 10.10.0.100, Local port: 179
Foreign host: 10.10.0.200, Foreign port: 42086
Nexthop: 10.10.0.100
Nexthop global: ::
Nexthop local: ::
BGP connection: shared network
BGP Connect Retry Timer in Seconds: 30
Estimated round trip time: 0 ms
BFD Hold Time (interval 30) timer expires in 0 seconds
Read thread: on  Write thread: on  FD used: 26

  BFD: Type: single hop
  Detect Multiplier: 3, Min Rx interval: 300, Min Tx interval: 300
  Status: Up, Last update: 0:00:00:01

Step 4: Run command protocols bgp show ip at DUT0 and check if output matches the following regular expressions:

1.1.1.0/24
Show output
BGP table version is 1, local router ID is 10.10.0.100, vrf id 0
Default local pref 100, local AS 10
local address -
Status codes:  s suppressed, d damped, h history, u unsorted, * valid, > best, = multipath,
               i internal, r RIB-failure, S Stale, R Removed
Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self
Origin codes:  i - IGP, e - EGP, ? - incomplete
RPKI validation codes: V valid, I invalid, N Not found

     Network          Next Hop            Metric LocPrf Weight Path
 *>  1.1.1.0/24       10.10.0.200              0             0 20 ?

Displayed 1 routes and 1 total paths

Step 5: Run command protocols ip show route at DUT0 and check if output matches the following regular expressions:

1.1.1.0/24
Show output
Codes: K - kernel route, C - connected, L - local, S - static,
       R - RIP, O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
       T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR,
       f - OpenFabric, t - Table-Direct,
       > - selected route, * - FIB route, q - queued, r - rejected, b - backup
       t - trapped, o - offload failure

IPv4 unicast VRF default:
B>* 1.1.1.0/24 [20/0] via 10.10.0.200, eth0, weight 1, 00:00:01
C>* 10.10.0.0/24 is directly connected, eth0, weight 1, 00:00:03
K * 10.10.0.0/24 [0/0] is directly connected, eth0, weight 1, 00:00:03
L>* 10.10.0.100/32 is directly connected, eth0, weight 1, 00:00:03

Step 6: Ping IP address 1.1.1.1 from DUT0:

admin@DUT0$ ping 1.1.1.1 count 1 size 56 timeout 1
Show output
PING 1.1.1.1 (1.1.1.1) 56(84) bytes of data.
64 bytes from 1.1.1.1: icmp_seq=1 ttl=64 time=0.293 ms

--- 1.1.1.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.293/0.293/0.293/0.000 ms

Step 7: Set the following configuration in DUT0 :

set interfaces ethernet eth0 address 10.10.0.100/24
set interfaces ethernet eth0 traffic policy local-out DROP
set protocols bgp 10 neighbor peer bfd
set protocols bgp 10 neighbor peer remote-address 10.10.0.200
set protocols bgp 10 neighbor peer remote-as 20
set protocols bgp 10 neighbor peer route-map import PERMIT
set protocols logging bgp bfd
set protocols logging bgp neighbor-events
set protocols logging level debugging
set protocols route-map PERMIT rule 1 action permit
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'
set traffic policy DROP rule 1 action drop
set traffic policy DROP rule 1 selector DROP
set traffic selector DROP rule 1 destination port 179
set traffic selector DROP rule 1 protocol tcp
set traffic selector DROP rule 2 protocol tcp
set traffic selector DROP rule 2 source port 179
set traffic selector DROP rule 3 destination port 3784
set traffic selector DROP rule 3 protocol udp

Step 8: Run command protocols bgp show ip neighbors at DUT0 and check if output matches the following regular expressions:

BGP state = (Connect|Idle)
Status: Down
BFD: Type: single hop
Show output
BGP neighbor is 10.10.0.200, remote AS 20, local AS 10, external link
  Local Role: undefined
  Remote Role: undefined
Hostname: osdx
  BGP version 4, remote router ID 10.10.0.200, local router ID 10.10.0.100
  BGP state = Idle
  Last read 00:00:05, Last write 00:00:05
  Hold time is 90 seconds, keepalive interval is 30 seconds
  Configured hold time is 90 seconds, keepalive interval is 30 seconds
  Configured tcp-mss is 0, synced tcp-mss is 0
  Configured conditional advertisements interval is 60 seconds
  Graceful restart information:
    Local GR Mode: Helper*
    Remote GR Mode: NotApplicable
    R bit: False
    N bit: False
    Timers:
      Configured Restart Time(sec): 120
      Received Restart Time(sec): 120
      Configured LLGR Stale Path Time(sec): 0
  Message statistics:
    Inq depth is 0
    Outq depth is 0
                         Sent       Rcvd
    Opens:                  2          1
    Notifications:          1          2
    Updates:                1          3
    Keepalives:             2          2
    Route Refresh:          1          2
    Capability:             0          0
    Total:                  7         10

  Prefix statistics:
    Inbound filtered: 0
    AS-PATH loop: 0
    Originator loop: 0
    Cluster loop: 0
    Invalid next-hop: 0
    Withdrawn: 0
    Attributes discarded: 0

  Minimum time between advertisement runs is 0 seconds

 For address family: IPv4 Unicast
  Not part of any update group
  Community attribute sent to this neighbor(all)
  Inbound path policy configured
  Route map for incoming advertisements is *PERMIT
  Outbound updates discarded due to missing policy
  0 accepted prefixes

  Connections established 1; dropped 1
  Last reset 00:00:01,  Peer closed the session (n/a)
  External BGP neighbor may be up to 1 hops away.
Local host: 10.10.0.100, Local port: 179
Foreign host: 10.10.0.200, Foreign port: 42086
Nexthop: 10.10.0.100
Nexthop global: ::
Nexthop local: ::
BGP connection: shared network
BGP Connect Retry Timer in Seconds: 30
Next start timer due in 0 seconds
BFD Hold Time (interval 30) timer expires in 0 seconds
Read thread: off  Write thread: off  FD used: -1

  BFD: Type: single hop
  Detect Multiplier: 3, Min Rx interval: 300, Min Tx interval: 300
  Status: Down, Last update: 0:00:00:30

Step 9: Run command protocols bgp show ip at DUT0 and check if output does not match the following regular expressions:

1.1.1.0/24
Show output
No BGP prefixes displayed, 0 exist

Step 10: Run command protocols ip show route at DUT0 and check if output does not match the following regular expressions:

1.1.1.0/24
Show output
Codes: K - kernel route, C - connected, L - local, S - static,
       R - RIP, O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
       T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR,
       f - OpenFabric, t - Table-Direct,
       > - selected route, * - FIB route, q - queued, r - rejected, b - backup
       t - trapped, o - offload failure

IPv4 unicast VRF default:
C>* 10.10.0.0/24 is directly connected, eth0, weight 1, 00:00:36
K * 10.10.0.0/24 [0/0] is directly connected, eth0, weight 1, 00:00:36
L>* 10.10.0.100/32 is directly connected, eth0, weight 1, 00:00:36

Step 11: Set the following configuration in DUT0 :

set interfaces ethernet eth0 address 10.10.0.100/24
set protocols bgp 10 neighbor peer bfd
set protocols bgp 10 neighbor peer remote-address 10.10.0.200
set protocols bgp 10 neighbor peer remote-as 20
set protocols bgp 10 neighbor peer route-map import PERMIT
set protocols logging bgp bfd
set protocols logging bgp neighbor-events
set protocols logging level debugging
set protocols route-map PERMIT rule 1 action permit
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'
set traffic policy DROP rule 1 action drop
set traffic policy DROP rule 1 selector DROP
set traffic selector DROP rule 1 destination port 179
set traffic selector DROP rule 1 protocol tcp
set traffic selector DROP rule 2 protocol tcp
set traffic selector DROP rule 2 source port 179
set traffic selector DROP rule 3 destination port 3784
set traffic selector DROP rule 3 protocol udp

Step 12: Run command protocols bgp show ip neighbors at DUT0 and check if output matches the following regular expressions:

BGP state = Established
Status: Up
BFD: Type: single hop
Show output
BGP neighbor is 10.10.0.200, remote AS 20, local AS 10, external link
  Local Role: undefined
  Remote Role: undefined
Hostname: osdx
  BGP version 4, remote router ID 10.10.0.200, local router ID 10.10.0.100
  BGP state = Established, up for 00:00:02
  Last read 00:00:01, Last write 00:00:01
  Hold time is 90 seconds, keepalive interval is 30 seconds
  Configured hold time is 90 seconds, keepalive interval is 30 seconds
  Configured tcp-mss is 0, synced tcp-mss is 1448
  Configured conditional advertisements interval is 60 seconds
  Neighbor capabilities:
    4 Byte AS: advertised and received
    AddPath:
      IPv4 Unicast: RX advertised and received
    Paths-Limit:
      IPv4 Unicast: advertised (0) and received (0)
    Long-lived Graceful Restart: advertised and received
      Address families by peer:
    Route refresh: advertised and received
    Enhanced Route Refresh: advertised and received
    Address Family IPv4 Unicast: advertised and received
    Hostname Capability: advertised (name: osdx,domain name: n/a) received (name: osdx,domain name: n/a)
    Version Capability: not advertised not received
    Link-Local Next Hop Capability: not advertised not received
    Graceful Restart Capability: advertised and received
      Remote Restart timer is 120 seconds
      Address families by peer:
        none
  Graceful restart information:
    End-of-RIB send: IPv4 Unicast
    End-of-RIB received: IPv4 Unicast
    Local GR Mode: Helper*
    Remote GR Mode: Helper
    R bit: True
    N bit: True
    Timers:
      Configured Restart Time(sec): 120
      Received Restart Time(sec): 120
      Configured LLGR Stale Path Time(sec): 0
    IPv4 Unicast:
      F bit: False
      End-of-RIB sent: Yes
      End-of-RIB sent after update: Yes
      End-of-RIB received: Yes
      Timers:
        Configured Stale Path Time(sec): 360
        LLGR Stale Path Time(sec): 0
  Message statistics:
    Inq depth is 0
    Outq depth is 0
                         Sent       Rcvd
    Opens:                  3          2
    Notifications:          1          2
    Updates:                2          5
    Keepalives:             3          3
    Route Refresh:          1          2
    Capability:             0          0
    Total:                 10         14

  Prefix statistics:
    Inbound filtered: 0
    AS-PATH loop: 0
    Originator loop: 0
    Cluster loop: 0
    Invalid next-hop: 0
    Withdrawn: 0
    Attributes discarded: 0

  Minimum time between advertisement runs is 0 seconds

 For address family: IPv4 Unicast
  Update group 2, subgroup 2
  Packet Queue length 0
  Community attribute sent to this neighbor(all)
  Inbound path policy configured
  Route map for incoming advertisements is *PERMIT
  Outbound updates discarded due to missing policy
  1 accepted, 0 sent prefixes

  Connections established 2; dropped 1
  Last reset never
  External BGP neighbor may be up to 1 hops away.
Local host: 10.10.0.100, Local port: 179
Foreign host: 10.10.0.200, Foreign port: 35334
Nexthop: 10.10.0.100
Nexthop global: fe80::dcad:beff:feef:6c00
Nexthop local: fe80::dcad:beff:feef:6c00
BGP connection: shared network
BGP Connect Retry Timer in Seconds: 30
Estimated round trip time: 4 ms
BFD Hold Time (interval 30) timer expires in 0 seconds
Read thread: on  Write thread: on  FD used: 25

  BFD: Type: single hop
  Detect Multiplier: 3, Min Rx interval: 300, Min Tx interval: 300
  Status: Up, Last update: 0:00:00:02

Step 13: Run command protocols bgp show ip at DUT0 and check if output matches the following regular expressions:

1.1.1.0/24
Show output
BGP table version is 3, local router ID is 10.10.0.100, vrf id 0
Default local pref 100, local AS 10
local address -
Status codes:  s suppressed, d damped, h history, u unsorted, * valid, > best, = multipath,
               i internal, r RIB-failure, S Stale, R Removed
Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self
Origin codes:  i - IGP, e - EGP, ? - incomplete
RPKI validation codes: V valid, I invalid, N Not found

     Network          Next Hop            Metric LocPrf Weight Path
 *>  1.1.1.0/24       10.10.0.200              0             0 20 ?

Displayed 1 routes and 1 total paths

Step 14: Run command protocols ip show route at DUT0 and check if output matches the following regular expressions:

1.1.1.0/24
Show output
Codes: K - kernel route, C - connected, L - local, S - static,
       R - RIP, O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
       T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR,
       f - OpenFabric, t - Table-Direct,
       > - selected route, * - FIB route, q - queued, r - rejected, b - backup
       t - trapped, o - offload failure

IPv4 unicast VRF default:
B>* 1.1.1.0/24 [20/0] via 10.10.0.200, eth0, weight 1, 00:00:01
C>* 10.10.0.0/24 is directly connected, eth0, weight 1, 00:00:39
K * 10.10.0.0/24 [0/0] is directly connected, eth0, weight 1, 00:00:39
L>* 10.10.0.100/32 is directly connected, eth0, weight 1, 00:00:39

Step 15: Ping IP address 1.1.1.1 from DUT0:

admin@DUT0$ ping 1.1.1.1 count 1 size 56 timeout 1
Show output
PING 1.1.1.1 (1.1.1.1) 56(84) bytes of data.
64 bytes from 1.1.1.1: icmp_seq=1 ttl=64 time=0.390 ms

--- 1.1.1.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.390/0.390/0.390/0.000 ms

Test eBGP multihop with BFD

Description

Test to check eBGP multihop with BFD protocol

Scenario

Step 1: Set the following configuration in DUT2 :

set interfaces ethernet eth0 address 10.10.0.101/24
set interfaces ethernet eth1 address 20.20.0.201/24
set protocols static route 1.1.1.0/24 next-hop 20.20.0.200
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 2: Set the following configuration in DUT1 :

set interfaces dummy dum0 address 1.1.1.1/24
set interfaces ethernet eth1 address 20.20.0.200/24
set protocols bgp 20 neighbor peer bfd
set protocols bgp 20 neighbor peer ebgp-multihop 2
set protocols bgp 20 neighbor peer remote-address 10.10.0.100
set protocols bgp 20 neighbor peer remote-as 10
set protocols bgp 20 neighbor peer route-map export PERMIT
set protocols bgp 20 redistribute connected route-map REDIS
set protocols logging bgp bfd
set protocols logging bgp neighbor-events
set protocols logging level debugging
set protocols route-map PERMIT rule 1 action permit
set protocols route-map REDIS rule 1 action permit
set protocols route-map REDIS rule 1 match interface dum0
set protocols static route 10.10.0.0/24 next-hop 20.20.0.201
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'

Step 3: Set the following configuration in DUT0 :

set interfaces ethernet eth0 address 10.10.0.100/24
set protocols bgp 10 neighbor peer bfd
set protocols bgp 10 neighbor peer ebgp-multihop 2
set protocols bgp 10 neighbor peer remote-address 20.20.0.200
set protocols bgp 10 neighbor peer remote-as 20
set protocols bgp 10 neighbor peer route-map import PERMIT
set protocols logging bgp bfd
set protocols logging bgp neighbor-events
set protocols logging level debugging
set protocols route-map PERMIT rule 1 action permit
set protocols static route 20.20.0.0/24 next-hop 10.10.0.101
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'
set traffic policy DROP rule 1 action drop
set traffic policy DROP rule 1 selector DROP
set traffic selector DROP rule 1 destination port 179
set traffic selector DROP rule 1 protocol tcp
set traffic selector DROP rule 2 protocol tcp
set traffic selector DROP rule 2 source port 179
set traffic selector DROP rule 3 destination port 4784
set traffic selector DROP rule 3 protocol udp

Step 4: Run command protocols bgp show ip neighbors at DUT0 and check if output matches the following regular expressions:

BGP state = Established
Status: Up
BFD: Type: multi hop
Show output
BGP neighbor is 20.20.0.200, remote AS 20, local AS 10, external link
  Local Role: undefined
  Remote Role: undefined
Hostname: osdx
  BGP version 4, remote router ID 20.20.0.200, local router ID 10.10.0.100
  BGP state = Established, up for 00:00:02
  Last read 00:00:01, Last write 00:00:01
  Hold time is 90 seconds, keepalive interval is 30 seconds
  Configured hold time is 90 seconds, keepalive interval is 30 seconds
  Configured tcp-mss is 0, synced tcp-mss is 1448
  Configured conditional advertisements interval is 60 seconds
  Neighbor capabilities:
    4 Byte AS: advertised and received
    AddPath:
      IPv4 Unicast: RX advertised and received
    Paths-Limit:
      IPv4 Unicast: advertised (0) and received (0)
    Long-lived Graceful Restart: advertised and received
      Address families by peer:
    Route refresh: advertised and received
    Enhanced Route Refresh: advertised and received
    Address Family IPv4 Unicast: advertised and received
    Hostname Capability: advertised (name: osdx,domain name: n/a) received (name: osdx,domain name: n/a)
    Version Capability: not advertised not received
    Link-Local Next Hop Capability: not advertised not received
    Graceful Restart Capability: advertised and received
      Remote Restart timer is 120 seconds
      Address families by peer:
        none
  Graceful restart information:
    End-of-RIB send: IPv4 Unicast
    End-of-RIB received: IPv4 Unicast
    Local GR Mode: Helper*
    Remote GR Mode: Helper
    R bit: True
    N bit: True
    Timers:
      Configured Restart Time(sec): 120
      Received Restart Time(sec): 120
      Configured LLGR Stale Path Time(sec): 0
    IPv4 Unicast:
      F bit: False
      End-of-RIB sent: Yes
      End-of-RIB sent after update: Yes
      End-of-RIB received: Yes
      Timers:
        Configured Stale Path Time(sec): 360
        LLGR Stale Path Time(sec): 0
  Message statistics:
    Inq depth is 0
    Outq depth is 0
                         Sent       Rcvd
    Opens:                  2          1
    Notifications:          1          0
    Updates:                1          3
    Keepalives:             1          1
    Route Refresh:          1          2
    Capability:             0          0
    Total:                  6          7

  Prefix statistics:
    Inbound filtered: 0
    AS-PATH loop: 0
    Originator loop: 0
    Cluster loop: 0
    Invalid next-hop: 0
    Withdrawn: 0
    Attributes discarded: 0

  Minimum time between advertisement runs is 0 seconds

 For address family: IPv4 Unicast
  Update group 1, subgroup 1
  Packet Queue length 0
  Community attribute sent to this neighbor(all)
  Inbound path policy configured
  Route map for incoming advertisements is *PERMIT
  Outbound updates discarded due to missing policy
  1 accepted, 0 sent prefixes

  Connections established 1; dropped 0
  Last reset never
  External BGP neighbor may be up to 2 hops away.
Local host: 10.10.0.100, Local port: 179
Foreign host: 20.20.0.200, Foreign port: 58928
Nexthop: 10.10.0.100
Nexthop global: ::
Nexthop local: ::
BGP connection: non shared network
BGP Connect Retry Timer in Seconds: 30
Estimated round trip time: 0 ms
BFD Hold Time (interval 30) timer expires in 0 seconds
Read thread: on  Write thread: on  FD used: 26

  BFD: Type: multi hop
  Detect Multiplier: 3, Min Rx interval: 300, Min Tx interval: 300
  Status: Up, Last update: 0:00:00:00

Step 5: Run command protocols bgp show ip at DUT0 and check if output matches the following regular expressions:

1.1.1.0/24
Show output
BGP table version is 1, local router ID is 10.10.0.100, vrf id 0
Default local pref 100, local AS 10
local address -
Status codes:  s suppressed, d damped, h history, u unsorted, * valid, > best, = multipath,
               i internal, r RIB-failure, S Stale, R Removed
Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self
Origin codes:  i - IGP, e - EGP, ? - incomplete
RPKI validation codes: V valid, I invalid, N Not found

     Network          Next Hop            Metric LocPrf Weight Path
 *>  1.1.1.0/24       20.20.0.200              0             0 20 ?

Displayed 1 routes and 1 total paths

Step 6: Run command protocols ip show route at DUT0 and check if output matches the following regular expressions:

1.1.1.0/24
Show output
Codes: K - kernel route, C - connected, L - local, S - static,
       R - RIP, O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
       T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR,
       f - OpenFabric, t - Table-Direct,
       > - selected route, * - FIB route, q - queued, r - rejected, b - backup
       t - trapped, o - offload failure

IPv4 unicast VRF default:
B>  1.1.1.0/24 [20/0] via 20.20.0.200 (recursive), weight 1, 00:00:02
  *                     via 10.10.0.101, eth0, weight 1, 00:00:02
C>* 10.10.0.0/24 is directly connected, eth0, weight 1, 00:00:03
K * 10.10.0.0/24 [0/0] is directly connected, eth0, weight 1, 00:00:03
L>* 10.10.0.100/32 is directly connected, eth0, weight 1, 00:00:03
S>* 20.20.0.0/24 [1/0] via 10.10.0.101, eth0, weight 1, 00:00:03

Step 7: Ping IP address 1.1.1.1 from DUT0:

admin@DUT0$ ping 1.1.1.1 count 1 size 56 timeout 1
Show output
PING 1.1.1.1 (1.1.1.1) 56(84) bytes of data.
64 bytes from 1.1.1.1: icmp_seq=1 ttl=63 time=0.550 ms

--- 1.1.1.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.550/0.550/0.550/0.000 ms

Step 8: Set the following configuration in DUT0 :

set interfaces ethernet eth0 address 10.10.0.100/24
set interfaces ethernet eth0 traffic policy local-out DROP
set protocols bgp 10 neighbor peer bfd
set protocols bgp 10 neighbor peer ebgp-multihop 2
set protocols bgp 10 neighbor peer remote-address 20.20.0.200
set protocols bgp 10 neighbor peer remote-as 20
set protocols bgp 10 neighbor peer route-map import PERMIT
set protocols logging bgp bfd
set protocols logging bgp neighbor-events
set protocols logging level debugging
set protocols route-map PERMIT rule 1 action permit
set protocols static route 20.20.0.0/24 next-hop 10.10.0.101
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'
set traffic policy DROP rule 1 action drop
set traffic policy DROP rule 1 selector DROP
set traffic selector DROP rule 1 destination port 179
set traffic selector DROP rule 1 protocol tcp
set traffic selector DROP rule 2 protocol tcp
set traffic selector DROP rule 2 source port 179
set traffic selector DROP rule 3 destination port 4784
set traffic selector DROP rule 3 protocol udp

Step 9: Run command protocols bgp show ip neighbors at DUT0 and check if output matches the following regular expressions:

BGP state = (Connect|Idle)
Status: Down
BFD: Type: multi hop
Show output
BGP neighbor is 20.20.0.200, remote AS 20, local AS 10, external link
  Local Role: undefined
  Remote Role: undefined
Hostname: osdx
  BGP version 4, remote router ID 20.20.0.200, local router ID 10.10.0.100
  BGP state = Idle
  Last read 00:00:05, Last write 00:00:05
  Hold time is 90 seconds, keepalive interval is 30 seconds
  Configured hold time is 90 seconds, keepalive interval is 30 seconds
  Configured tcp-mss is 0, synced tcp-mss is 0
  Configured conditional advertisements interval is 60 seconds
  Graceful restart information:
    Local GR Mode: Helper*
    Remote GR Mode: NotApplicable
    R bit: False
    N bit: False
    Timers:
      Configured Restart Time(sec): 120
      Received Restart Time(sec): 120
      Configured LLGR Stale Path Time(sec): 0
  Message statistics:
    Inq depth is 0
    Outq depth is 0
                         Sent       Rcvd
    Opens:                  2          1
    Notifications:          1          2
    Updates:                1          3
    Keepalives:             2          2
    Route Refresh:          1          2
    Capability:             0          0
    Total:                  7         10

  Prefix statistics:
    Inbound filtered: 0
    AS-PATH loop: 0
    Originator loop: 0
    Cluster loop: 0
    Invalid next-hop: 0
    Withdrawn: 0
    Attributes discarded: 0

  Minimum time between advertisement runs is 0 seconds

 For address family: IPv4 Unicast
  Not part of any update group
  Community attribute sent to this neighbor(all)
  Inbound path policy configured
  Route map for incoming advertisements is *PERMIT
  Outbound updates discarded due to missing policy
  0 accepted prefixes

  Connections established 1; dropped 1
  Last reset 00:00:01,  Peer closed the session (n/a)
  External BGP neighbor may be up to 2 hops away.
Local host: 10.10.0.100, Local port: 179
Foreign host: 20.20.0.200, Foreign port: 58928
Nexthop: 10.10.0.100
Nexthop global: ::
Nexthop local: ::
BGP connection: non shared network
BGP Connect Retry Timer in Seconds: 30
Next start timer due in 0 seconds
BFD Hold Time (interval 30) timer expires in 0 seconds
Read thread: off  Write thread: off  FD used: -1

  BFD: Type: multi hop
  Detect Multiplier: 3, Min Rx interval: 300, Min Tx interval: 300
  Status: Down, Last update: 0:00:00:30

Step 10: Run command protocols bgp show ip at DUT0 and check if output does not match the following regular expressions:

1.1.1.0/24
Show output
No BGP prefixes displayed, 0 exist

Step 11: Run command protocols ip show route at DUT0 and check if output does not match the following regular expressions:

1.1.1.0/24
Show output
Codes: K - kernel route, C - connected, L - local, S - static,
       R - RIP, O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
       T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR,
       f - OpenFabric, t - Table-Direct,
       > - selected route, * - FIB route, q - queued, r - rejected, b - backup
       t - trapped, o - offload failure

IPv4 unicast VRF default:
C>* 10.10.0.0/24 is directly connected, eth0, weight 1, 00:00:35
K * 10.10.0.0/24 [0/0] is directly connected, eth0, weight 1, 00:00:35
L>* 10.10.0.100/32 is directly connected, eth0, weight 1, 00:00:35
S>* 20.20.0.0/24 [1/0] via 10.10.0.101, eth0, weight 1, 00:00:35

Step 12: Set the following configuration in DUT0 :

set interfaces ethernet eth0 address 10.10.0.100/24
set protocols bgp 10 neighbor peer bfd
set protocols bgp 10 neighbor peer ebgp-multihop 2
set protocols bgp 10 neighbor peer remote-address 20.20.0.200
set protocols bgp 10 neighbor peer remote-as 20
set protocols bgp 10 neighbor peer route-map import PERMIT
set protocols logging bgp bfd
set protocols logging bgp neighbor-events
set protocols logging level debugging
set protocols route-map PERMIT rule 1 action permit
set protocols static route 20.20.0.0/24 next-hop 10.10.0.101
set system login user admin authentication encrypted-password '$6$GSjsCj8gHLv$/VcqU6FLi6CT2Oxn0MJQ2C2tqnRDrYKNF8HIYWJp68nvXvPdFccDsT04.WtigUONbKYrgKg8d6rEs8PjljMkH0'
set traffic policy DROP rule 1 action drop
set traffic policy DROP rule 1 selector DROP
set traffic selector DROP rule 1 destination port 179
set traffic selector DROP rule 1 protocol tcp
set traffic selector DROP rule 2 protocol tcp
set traffic selector DROP rule 2 source port 179
set traffic selector DROP rule 3 destination port 4784
set traffic selector DROP rule 3 protocol udp

Step 13: Run command protocols bgp show ip neighbors at DUT0 and check if output matches the following regular expressions:

BGP state = Established
Status: Up
BFD: Type: multi hop
Show output
BGP neighbor is 20.20.0.200, remote AS 20, local AS 10, external link
  Local Role: undefined
  Remote Role: undefined
Hostname: osdx
  BGP version 4, remote router ID 20.20.0.200, local router ID 10.10.0.100
  BGP state = Established, up for 00:00:02
  Last read 00:00:01, Last write 00:00:01
  Hold time is 90 seconds, keepalive interval is 30 seconds
  Configured hold time is 90 seconds, keepalive interval is 30 seconds
  Configured tcp-mss is 0, synced tcp-mss is 1448
  Configured conditional advertisements interval is 60 seconds
  Neighbor capabilities:
    4 Byte AS: advertised and received
    AddPath:
      IPv4 Unicast: RX advertised and received
    Paths-Limit:
      IPv4 Unicast: advertised (0) and received (0)
    Long-lived Graceful Restart: advertised and received
      Address families by peer:
    Route refresh: advertised and received
    Enhanced Route Refresh: advertised and received
    Address Family IPv4 Unicast: advertised and received
    Hostname Capability: advertised (name: osdx,domain name: n/a) received (name: osdx,domain name: n/a)
    Version Capability: not advertised not received
    Link-Local Next Hop Capability: not advertised not received
    Graceful Restart Capability: advertised and received
      Remote Restart timer is 120 seconds
      Address families by peer:
        none
  Graceful restart information:
    End-of-RIB send: IPv4 Unicast
    End-of-RIB received: IPv4 Unicast
    Local GR Mode: Helper*
    Remote GR Mode: Helper
    R bit: True
    N bit: True
    Timers:
      Configured Restart Time(sec): 120
      Received Restart Time(sec): 120
      Configured LLGR Stale Path Time(sec): 0
    IPv4 Unicast:
      F bit: False
      End-of-RIB sent: Yes
      End-of-RIB sent after update: Yes
      End-of-RIB received: Yes
      Timers:
        Configured Stale Path Time(sec): 360
        LLGR Stale Path Time(sec): 0
  Message statistics:
    Inq depth is 0
    Outq depth is 0
                         Sent       Rcvd
    Opens:                  3          2
    Notifications:          1          2
    Updates:                2          5
    Keepalives:             3          3
    Route Refresh:          1          2
    Capability:             0          0
    Total:                 10         14

  Prefix statistics:
    Inbound filtered: 0
    AS-PATH loop: 0
    Originator loop: 0
    Cluster loop: 0
    Invalid next-hop: 0
    Withdrawn: 0
    Attributes discarded: 0

  Minimum time between advertisement runs is 0 seconds

 For address family: IPv4 Unicast
  Update group 2, subgroup 2
  Packet Queue length 0
  Community attribute sent to this neighbor(all)
  Inbound path policy configured
  Route map for incoming advertisements is *PERMIT
  Outbound updates discarded due to missing policy
  1 accepted, 0 sent prefixes

  Connections established 2; dropped 1
  Last reset never
  External BGP neighbor may be up to 2 hops away.
Local host: 10.10.0.100, Local port: 179
Foreign host: 20.20.0.200, Foreign port: 36678
Nexthop: 10.10.0.100
Nexthop global: fe80::dcad:beff:feef:6c00
Nexthop local: fe80::dcad:beff:feef:6c00
BGP connection: non shared network
BGP Connect Retry Timer in Seconds: 30
Estimated round trip time: 5 ms
BFD Hold Time (interval 30) timer expires in 0 seconds
Read thread: on  Write thread: on  FD used: 25

  BFD: Type: multi hop
  Detect Multiplier: 3, Min Rx interval: 300, Min Tx interval: 300
  Status: Up, Last update: 0:00:00:01

Step 14: Run command protocols bgp show ip at DUT0 and check if output matches the following regular expressions:

1.1.1.0/24
Show output
BGP table version is 3, local router ID is 10.10.0.100, vrf id 0
Default local pref 100, local AS 10
local address -
Status codes:  s suppressed, d damped, h history, u unsorted, * valid, > best, = multipath,
               i internal, r RIB-failure, S Stale, R Removed
Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self
Origin codes:  i - IGP, e - EGP, ? - incomplete
RPKI validation codes: V valid, I invalid, N Not found

     Network          Next Hop            Metric LocPrf Weight Path
 *>  1.1.1.0/24       20.20.0.200              0             0 20 ?

Displayed 1 routes and 1 total paths

Step 15: Run command protocols ip show route at DUT0 and check if output matches the following regular expressions:

1.1.1.0/24
Show output
Codes: K - kernel route, C - connected, L - local, S - static,
       R - RIP, O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
       T - Table, v - VNC, V - VNC-Direct, A - Babel, F - PBR,
       f - OpenFabric, t - Table-Direct,
       > - selected route, * - FIB route, q - queued, r - rejected, b - backup
       t - trapped, o - offload failure

IPv4 unicast VRF default:
B>  1.1.1.0/24 [20/0] via 20.20.0.200 (recursive), weight 1, 00:00:01
  *                     via 10.10.0.101, eth0, weight 1, 00:00:01
C>* 10.10.0.0/24 is directly connected, eth0, weight 1, 00:00:38
K * 10.10.0.0/24 [0/0] is directly connected, eth0, weight 1, 00:00:38
L>* 10.10.0.100/32 is directly connected, eth0, weight 1, 00:00:38
S>* 20.20.0.0/24 [1/0] via 10.10.0.101, eth0, weight 1, 00:00:38

Step 16: Ping IP address 1.1.1.1 from DUT0:

admin@DUT0$ ping 1.1.1.1 count 1 size 56 timeout 1
Show output
PING 1.1.1.1 (1.1.1.1) 56(84) bytes of data.
64 bytes from 1.1.1.1: icmp_seq=1 ttl=63 time=0.450 ms

--- 1.1.1.1 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.450/0.450/0.450/0.000 ms