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During BGP MD5 key change, TCP session goes down

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This article describes the version different behavior about BGP Message Digest 5 (MD5) changes by neighbor authentication-key.

BGP MD5 is an important feature to protect the sessions, or filter unwanted session packets. Company policy sometimes requires changing BGP MD5 regularly. The change window should not show any TCP session drop. However, the following syslog message is logged, showing that the TCP session is immediately dropped.

Jan 1 11:28:36.771488 bgp_peer_delete:7199: NOTIFICATION sent to 10.0.0.1 (Internal AS 65000): code 6 (Cease) subcode 3 (Peer Unconfigured), Reason: Peer Deletion

Junos OS should initialize the authentication database to establish TCP session for new MD5 key, so it drops TCP session to establish for new MD5 key. Here is an example showing how it drops.

Topology

R1 ---------------------------- R2
10.0.0.1                     10.0.0.2

BGP session established

lab@jnpr1# set logical-systems R1 protocols BGP group iBGP neighbor 10.0.0.2 authentication-key juniper 
lab@# set logical-systems R2 protocols BGP group iBGP neighbor 10.0.0.1 authentication-key juniper 

lab@jnpr1# run show system connections | match .179 
tcp4 0 0 10.0.0.2.179 10.0.0.1.63822 ESTABLISHED
tcp4 0 0 10.0.0.1.63822 10.0.0.2.179 ESTABLISHED
tcp46 0 0 *.179 *.* LISTEN
tcp4 0 0 *.179 *.* LISTEN
tcp46 0 0 *.179 *.* LISTEN
tcp4 0 0 *.179 *.* LISTEN

lab@jnpr1:R1> show BGP neighbor 
Peer: 10.0.0.2+179 AS 65000 Local: 10.0.0.1+51486 AS 65000
Type: Internal State: Established Flags: <Sync>
Last State: OpenConfirm Last Event: RecvKeepAlive
Last Error: None
Options: <Preference AuthKey PeerAS Refresh>
Authentication key is configured   >>>>> auth-key enabled
Holdtime: 90 Preference: 170
Number of flaps: 0
Peer ID: 10.0.0.2 Local ID: 10.0.0.1 Active Holdtime: 90
Keepalive Interval: 30 Peer index: 0 
BFD: disabled, down
...snipped...
Last traffic (seconds): Received 16 Sent 11 Checked 1 
Input messages: Total 8	Updates 1 Refreshes 0 Octets 156
Output messages: Total 9	Updates 0 Refreshes 0 Octets 234
Output Queue[0]: 0
Trace options: all
Trace file: /var/log/R1/R1-BGP.log size 131072 files 10   >>>>> traceoption enabled

lab@jnpr1:R2> show BGP neighbor 
Peer: 10.0.0.1+179 AS 65000 Local: 10.0.0.2+51910 AS 65000
Type: Internal State: Established Flags: <ImportEval Sync>
Last State: OpenConfirm Last Event: RecvKeepAlive
Last Error: None
Options: <Preference AuthKey PeerAS Refresh>
Authentication key is configured  >>>>>>>> auth-key enabled
Holdtime: 90 Preference: 170
Number of flaps: 0
Peer ID: 10.0.0.1 Local ID: 10.0.0.2 Active Holdtime: 90
Keepalive Interval: 30 Peer index: 0 
BFD: disabled, down
...snipped...
Last traffic (seconds): Received 0 Sent 0 Checked 0 
Input messages: Total 2	Updates 1 Refreshes 0 Octets 42
Output messages: Total 3	Updates 0 Refreshes 0 Octets 120
Output Queue[0]: 0
Trace options: all
Trace file: /var/log/R2/R2-BGP.log size 131072 files 10 >>>> traceoption enabled

Changed MD5 key on R2

lab@jnpr1# set logical-systems R2 protocols BGP group iBGP neighbor 10.0.0.1 authentication-key juniper
[edit]
lab@jnpr1# commit 
commit complete

lab@jnpr1:R1> 
*** R1/R1-BGP.log ***
Jan 1 11:28:15.144581 bgp_keepalive_timeout: peer 10.0.0.2 (Internal AS 65000) last checked 11 last recv'd 22 last sent 27 last keepalive 27
Jan 1 11:28:15.144813 bgp_send: sending 19 bytes to 10.0.0.2 (Internal AS 65000)
Jan 1 11:28:15.144881 
Jan 1 11:28:15.144881 BGP SEND 10.0.0.1+179 -> 10.0.0.2+51910
Jan 1 11:28:15.144963 BGP SEND message type 4 (KeepAlive) length 19
Jan 1 11:28:20.871109 task_process_events: recv ready for BGP_65000.10.0.0.2+51910
Jan 1 11:28:20.871314 task_job_create_background: create prio 4 job Read peer for task BGP_65000.10.0.0.2+51910
Jan 1 11:28:20.871480 background dispatch running job Read peer for task BGP_65000.10.0.0.2+51910
Jan 1 11:28:20.871559 bgp_read_v4_message: receiving packet(s) from 10.0.0.2 (Internal AS 65000)
Jan 1 11:28:20.871677 
Jan 1 11:28:20.871677 BGP RECV 10.0.0.2+51910 -> 10.0.0.1+179
Jan 1 11:28:20.871762 BGP RECV message type 4 (KeepAlive) length 19
Jan 1 11:28:20.871835 bgp_read_v4_message: done with 10.0.0.2 (Internal AS 65000) received 19 octets 0 updates 0 routes
Jan 1 11:28:20.871899 task_job_delete: delete background job Read peer for task BGP_65000.10.0.0.2+51910
Jan 1 11:28:20.872082 background dispatch completed job Read peer for task BGP_65000.10.0.0.2+51910
Jan 1 11:28:24.044161 bgp_reuse_scan: Starting scan
Jan 1 11:28:36.750919 task_timer_uset: timer BGP_RT_Background_BGP Route statistics timer <Touched> set to interval 30 at 11:28:54
Jan 1 11:28:36.751128 bgp_rt_update_med_igp_init: Deleting MED IGP update timer
Jan 1 11:28:36.752943 init BGP commit sync

Jan 1 11:28:36.753216 no import processing required.
Jan 1 11:28:36.753273 Into post reconfig
Jan 1 11:28:36.754669 rt_flash_update_callback: flash BGP_Group_iBGP (inet.0) start
Jan 1 11:28:36.754789 rt_flash_update_callback: flash BGP_Group_iBGP (inet.0) done
Jan 1 11:28:40.675535 bgp_keepalive_timeout: peer 10.0.0.2 (Internal AS 65000) last checked 36 last recv'd 19 last sent 25 last keepalive 25
Jan 1 11:28:40.675768 bgp_send: sending 19 bytes to 10.0.0.2 (Internal AS 65000)
Jan 1 11:28:40.675900 
Jan 1 11:28:40.675900 BGP SEND 10.0.0.1+179 -> 10.0.0.2+51910
Jan 1 11:28:40.675986 BGP SEND message type 4 (KeepAlive) length 19

lab@jnpr1:R2> 
*** R2/R2-BGP.log ***
Jan 1 11:28:15.146621 BGP RECV 10.0.0.1+179 -> 10.0.0.2+51910
Jan 1 11:28:15.146706 BGP RECV message type 4 (KeepAlive) length 19
Jan 1 11:28:15.146778 bgp_read_v4_message: done with 10.0.0.1 (Internal AS 65000) received 19 octets 0 updates 0 routes
Jan 1 11:28:15.146842 task_job_delete: delete background job Read peer for task BGP_65000.10.0.0.1+179
Jan 1 11:28:15.147151 background dispatch completed job Read peer for task BGP_65000.10.0.0.1+179
Jan 1 11:28:20.869676 bgp_keepalive_timeout: peer 10.0.0.1 (Internal AS 65000) last checked 17 last recv'd 6 last sent 28 last keepalive 28
Jan 1 11:28:20.869900 bgp_send: sending 19 bytes to 10.0.0.1 (Internal AS 65000)
Jan 1 11:28:20.869967 
Jan 1 11:28:20.869967 BGP SEND 10.0.0.2+51910 -> 10.0.0.1+179
Jan 1 11:28:20.870047 BGP SEND message type 4 (KeepAlive) length 19
Jan 1 11:28:21.583545 bgp_reuse_scan: Starting scan
Jan 1 11:28:22.397416 bgp_down_peer_timeout: BGP_65000.10.0.0.1+179_Down Peer Timer
Jan 1 11:28:22.397652 task_timer_delete: BGP_65000.10.0.0.1+179_Down Peer Timer <Processing>
Jan 1 11:28:36.725924 bgp_conf_compile: Processing node 9069160
Jan 1 11:28:36.726983 bgp_conf_compile: Processing dependent 94a0000. Next thread: 9069168 9069168
Jan 1 11:28:36.727059 bgp_conf_compile: Node 94a0000 dependency: 94a1000 94a1000
Jan 1 11:28:36.727112 bgp_conf_compile: Processing node 94a0000
Jan 1 11:28:36.727165 bgp_conf_compile: Processing dependent 94a1000. Next thread: 94a0008 94a0008
Jan 1 11:28:36.727223 bgp_conf_compile: Node 94a1000 addr 10.0.0.1 Next 94a0008
Jan 1 11:28:36.727341 bgp_conf_group_add: Reusing existing group at 9298000
Jan 1 11:28:36.727401 bgp_group_reuse: Has peer 10.0.0.1 (deleted)
Jan 1 11:28:36.727518 bgp_peer_can_reuse: Can't reuse session for 10.0.0.1 because options mismatch
Jan 1 11:28:36.727602 bgp_conf_peer_add: Creating new peer for 10.0.0.1
Jan 1 11:28:36.771488 bgp_peer_delete:7199: NOTIFICATION sent to 10.0.0.1 (Internal AS 65000): code 6 (Cease) subcode 3 (Peer Unconfigured), Reason: Peer Deletion      >>>>>>>>>>> R2 received code 6 (Cease) subcode 3 (Peer Unconfigured)
Jan 1 11:28:36.771619 bgp_send: sending 21 bytes to 10.0.0.1 (Internal AS 65000)
Jan 1 11:28:36.771685 
Jan 1 11:28:36.771685 BGP SEND 10.0.0.2+51910 -> 10.0.0.1+179
Jan 1 11:28:36.771766 BGP SEND message type 3 (Notification) length 21
Jan 1 11:28:36.771821 BGP SEND Notification code 6 (Cease) subcode 3 (Peer Unconfigured)
Jan 1 11:28:36.778896 task_job_create_background: create prio 4 job RT closing job for task BGP_RT_Background
Jan 1 11:28:36.780486 task_timer_uset: timer BGP_RT_Background_BGP Route statistics timer <Touched> set to interval 30 at 11:29:06
Jan 1 11:28:36.780585 bgp_rt_update_med_igp_init: Deleting MED IGP update timer
Jan 1 11:28:36.780675 task_alloc: allocated task block for BGP_65000 priority 50
Jan 1 11:28:36.781537 task_create: BGP_65000.10.0.0.1 rt_proto <BGP>
Jan 1 11:28:36.781631 bgp_event: peer 10.0.0.1 (Internal AS 65000) old state Idle event Start new state Active
Jan 1 11:28:36.781715 task_timer_ucreate: created timer BGP_65000.10.0.0.1_Task parent flags <>
Jan 1 11:28:36.781780 task_timer_ucreate: created timer BGP_65000.10.0.0.1_Connect flags <>
Jan 1 11:28:36.781867 task_timer_uset: timer BGP_65000.10.0.0.1_Connect <Touched> set to offset 12 at 11:28:48
Jan 1 11:28:36.782023 task_timer_ucreate: created timer BGP_65000.10.0.0.1_Down Peer Timer flags <>
Jan 1 11:28:36.782107 task_timer_uset: timer BGP_65000.10.0.0.1_Down Peer Timer <Touched> set to offset 2:00 at 11:30:36

When R1 changes the MD5 key under state pre-established by MD5 key, R1 sends out BGP notification code 6 (Cease) subcode 3 (Peer Unconfigured) to R2. R2 then drops the BGP session.

You can find out what any BGP error code indicates at the following URL: https://www.iana.org/assignments/bgp-parameters/bgp-parameters.xhtml#bgp-parameters-3

In version 12.3R, the BGP session does not disconnect the neighbor immediately, even though BGP MD5 changes. It holds the session until the timer expires. Please see the following syslog message.

Jan 1 12:36:52.749550 bgp_hold_timeout:4032: NOTIFICATION sent to 10.0.0.2 (Internal AS 65000): code 4 (Hold Timer Expired Error), Reason: holdtime expired for 10.0.0.2 (Internal AS 65000), socket buffer sndcc: 57 rcvcc: 0 TCP state: 4, snd_una: 4258156560 snd_nxt:

This behavior makes MD5 changes more flexible without any TCP drops. Of course as long as you change until BGP hold timer expire. The best practice is to modify the MD5 quickly until BGP session expires.

Tested version 12.3R1.7

lab@jnpr1:R1> 
*** R1/R1-BGP.log ***
Jan 1 12:35:22.916505 task_process_events: recv ready for BGP_65000.10.0.0.2+179
Jan 1 12:35:22.916712 task_job_create_background: create prio 4 job Read peer for task BGP_65000.10.0.0.2+179
Jan 1 12:35:22.916904 background dispatch running job Read peer for task BGP_65000.10.0.0.2+179
Jan 1 12:35:22.916971 bgp_read_v4_message: receiving packet(s) from 10.0.0.2 (Internal AS 65000)
Jan 1 12:35:22.917087 
Jan 1 12:35:22.917087 BGP RECV 10.0.0.2+179 -> 10.0.0.1+58090
Jan 1 12:35:22.917174 BGP RECV message type 4 (KeepAlive) length 19
Jan 1 12:35:22.917250 bgp_read_v4_message: done with 10.0.0.2 (Internal AS 65000) received 19 octets 0 updates 0 routes
Jan 1 12:35:22.917315 task_job_delete: delete background job Read peer for task BGP_65000.10.0.0.2+179
Jan 1 12:35:22.917502 background dispatch completed job Read peer for task BGP_65000.10.0.0.2+179
Jan 1 12:35:24.635751 bgp_keepalive_timeout: peer 10.0.0.2 (Internal AS 65000) last checked 48 last recv'd 1 last sent 28 last keepalive 28
Jan 1 12:35:24.635990 bgp_send: sending 19 bytes to 10.0.0.2 (Internal AS 65000)
Jan 1 12:35:24.636060 
Jan 1 12:35:24.636060 BGP SEND 10.0.0.1+58090 -> 10.0.0.2+179
Jan 1 12:35:24.636146 BGP SEND message type 4 (KeepAlive) length 19
Jan 1 12:35:28.031189 bgp_reuse_scan: Starting scan
Jan 1 12:35:47.942284 bgp_reuse_scan: Starting scan
Jan 1 12:35:50.094756 bgp_keepalive_timeout: peer 10.0.0.2 (Internal AS 65000) last checked 74 last recv'd 27 last sent 26 last keepalive 26
Jan 1 12:35:50.095018 bgp_send: sending 19 bytes to 10.0.0.2 (Internal AS 65000)
Jan 1 12:35:50.095090 
Jan 1 12:35:50.095090 BGP SEND 10.0.0.1+58090 -> 10.0.0.2+179
Jan 1 12:35:50.095178 BGP SEND message type 4 (KeepAlive) length 19
Jan 1 12:35:55.747861 bgp_hold_timeout: peer 10.0.0.2 (Internal AS 65000) last checked 80 last recv'd 33 last sent 6 last keepalive 6
Jan 1 12:35:55.748142 task_timer_reset: reset BGP_65000.10.0.0.2+179_Hold
Jan 1 12:35:55.748223 task_timer_set_oneshot_latest: timer BGP_65000.10.0.0.2+179_Hold interval set to 57
Jan 1 12:36:07.895923 bgp_reuse_scan: Starting scan
Jan 1 12:36:15.638735 bgp_keepalive_timeout: peer 10.0.0.2 (Internal AS 65000) last checked 19 last recv'd 52 last sent 25 last keepalive 25
Jan 1 12:36:15.638983 bgp_send: sending 19 bytes to 10.0.0.2 (Internal AS 65000)
Jan 1 12:36:15.639053 
Jan 1 12:36:15.639053 BGP SEND 10.0.0.1+58090 -> 10.0.0.2+179
Jan 1 12:36:15.639140 BGP SEND message type 4 (KeepAlive) length 19
Jan 1 12:36:27.758815 bgp_reuse_scan: Starting scan
Jan 1 12:36:45.522041 bgp_keepalive_timeout: peer 10.0.0.2 (Internal AS 65000) last checked 49 last recv'd 82 last sent 30 last keepalive 30
Jan 1 12:36:45.522302 bgp_send: sending 19 bytes to 10.0.0.2 (Internal AS 65000)
Jan 1 12:36:45.522372 
Jan 1 12:36:45.522372 BGP SEND 10.0.0.1+58090 -> 10.0.0.2+179
Jan 1 12:36:45.522460 BGP SEND message type 4 (KeepAlive) length 19
Jan 1 12:36:47.700758 bgp_reuse_scan: Starting scan
Jan 1 12:36:52.747901 bgp_hold_timeout: peer 10.0.0.2 (Internal AS 65000) last checked 57 last recv'd 90 last sent 8 last keepalive 8
Jan 1 12:36:52.749550 bgp_hold_timeout:4032: NOTIFICATION sent to 10.0.0.2 (Internal AS 65000): code 4 (Hold Timer Expired Error), Reason: holdtime expired for 10.0.0.2 (Internal AS 65000), socket buffer sndcc: 57 rcvcc: 0 TCP state: 4, snd_una: 4258156560 snd_nxt: 4258156598 snd_wnd: 16384 rcv_nxt: 1400263074 rcv_adv: 1400279995, hold timer out 90s, hold timer remain 0s
Jan 1 12:36:52.749725 bgp_send: sending 21 bytes to 10.0.0.2 (Internal AS 65000)
Jan 1 12:36:52.749815 
Jan 1 12:36:52.749815 BGP SEND 10.0.0.1+58090 -> 10.0.0.2+179
Jan 1 12:36:52.756026 BGP SEND message type 3 (Notification) length 21
Jan 1 12:36:52.761489 BGP SEND Notification code 4 (Hold Timer Expired Error) subcode 0 (unused)
Jan 1 12:36:52.761795 bgp_peer_close: closing peer 10.0.0.2 (Internal AS 65000), state is 7 (Established)
Jan 1 12:36:52.761932 bgp_event: peer 10.0.0.2 (Internal AS 65000) old state Established event HoldTime new state Idle
Jan 1 12:36:52.762792 bgp_close_socket: peer 10.0.0.2 (Internal AS 65000)
Jan 1 12:36:52.762928 task_close: close socket 34 task BGP_65000.10.0.0.2+179
Jan 1 12:36:52.762991 task_reset_socket: task BGP_65000.10.0.0.2+179 socket 34
Jan 1 12:36:52.764230 task_timer_delete: BGP_65000.10.0.0.2_Keepalive <Latest>
Jan 1 12:36:52.764389 task_timer_delete: BGP_65000.10.0.0.2_Hold <Processing>
Jan 1 12:36:52.778716 task_job_create_background: create prio 4 job BGP closing job for task BGP_RT_Background
Jan 1 12:36:52.779043 background dispatch running job BGP closing job for task BGP_RT_Background
Jan 1 12:36:52.786822 bgp_reset_flash: resetting flash/new policy routes for BGP_Group_iBGP
Jan 1 12:36:52.787000 bgp_rtbit_free: Clearing bit 0x10000
Jan 1 12:36:52.787151 (add-path) Reseting ADDPATH bits set for peer 10.0.0.2 (Internal AS 65000), (bit: 0)
Jan 1 12:36:52.787239 bgp_event: peer 10.0.0.2 (Internal AS 65000) old state Idle event Start new state Active
Jan 1 12:36:52.787336 task_timer_ucreate: created timer BGP_65000.10.0.0.2_Connect flags <>
Jan 1 12:36:52.787476 task_timer_uset: timer BGP_65000.10.0.0.2_Connect <Touched> set to offset 32 at 12:37:24
Jan 1 12:36:52.787547 task_job_delete: delete background job BGP closing job for task BGP_RT_Background
Jan 1 12:36:52.787652 background dispatch completed job BGP closing job for task BGP_RT_Background
Jan 1 12:37:07.617526 bgp_reuse_scan: Starting scan
Jan 1 12:37:24.780867 bgp_connect_timeout: BGP_65000.10.0.0.2_Connect
Jan 1 12:37:24.781315 bgp_connect_start: peer 10.0.0.2 (Internal AS 65000)
Jan 1 12:37:24.781378 bgp_event: peer 10.0.0.2 (Internal AS 65000) old state Active event ConnectRetry new state Connect
Jan 1 12:37:24.783485 task_get_socket: domain AF_INET type SOCK_STREAM protocol 0 socket 34
Jan 1 12:37:24.783668 task_set_socket: task BGP_65000.10.0.0.2 socket 34
Jan 1 12:37:24.783842 task_set_option_internal: task BGP_65000.10.0.0.2 socket 34 option NonBlocking(8) value 1
Jan 1 12:37:24.783926 task_set_option_internal: task BGP_65000.10.0.0.2 socket 34 option ReUsePort(38) value 1
Jan 1 12:37:24.784006 task_set_option_internal: task BGP_65000.10.0.0.2 socket 34 option PathMTUDiscovery(26) value 0
Jan 1 12:37:24.784088 task_set_option_internal: task BGP_65000.10.0.0.2 socket 34 option TOS(16) value 192
Jan 1 12:37:24.784617 task_connect: task BGP_65000.10.0.0.2+179 addr 10.0.0.2+179task_timer_reset: reset BGP_65000.10.0.0.2+179_Connect
Jan 1 12:37:24.784741 task_timer_set_oneshot_latest: timer BGP_65000.10.0.0.2+179_Connect interval set to 32
Jan 1 12:37:27.551395 bgp_reuse_scan: Starting scan
lab@jnpr1:R2> 
*** R2/R2-BGP.log ***
Jan 1 12:35:24.637177 task_process_events: recv ready for BGP_65000.10.0.0.1+58090
Jan 1 12:35:24.637394 task_job_create_background: create prio 4 job Read peer for task BGP_65000.10.0.0.1+58090
Jan 1 12:35:24.637570 background dispatch running job Read peer for task BGP_65000.10.0.0.1+58090
Jan 1 12:35:24.637652 bgp_read_v4_message: receiving packet(s) from 10.0.0.1 (Internal AS 65000)
Jan 1 12:35:24.637766 
Jan 1 12:35:24.637766 BGP RECV 10.0.0.1+58090 -> 10.0.0.2+179
Jan 1 12:35:24.637856 BGP RECV message type 4 (KeepAlive) length 19
Jan 1 12:35:24.637931 bgp_read_v4_message: done with 10.0.0.1 (Internal AS 65000) received 19 octets 0 updates 0 routes
Jan 1 12:35:24.637997 task_job_delete: delete background job Read peer for task BGP_65000.10.0.0.1+58090
Jan 1 12:35:24.638183 background dispatch completed job Read peer for task BGP_65000.10.0.0.1+58090
Jan 1 12:35:27.890229 bgp_reuse_scan: Starting scan
Jan 1 12:35:47.835297 bgp_reuse_scan: Starting scan
Jan 1 12:35:50.618849 bgp_conf_compile: Processing node 90b20a0
Jan 1 12:35:50.635006 bgp_conf_compile: Processing dependent 94f4000. Next thread: 90b20a8 90b20a8
Jan 1 12:35:50.635065 bgp_conf_compile: Node 94f4000 dependency: 94f5000 94f5000
Jan 1 12:35:50.635119 bgp_conf_compile: Processing node 94f4000
Jan 1 12:35:50.635174 bgp_conf_compile: Processing dependent 94f5000. Next thread: 94f4008 94f4008
Jan 1 12:35:50.635236 bgp_conf_compile: Node 94f5000 addr 10.0.0.1 Next 94f4008
Jan 1 12:35:50.635379 bgp_conf_group_add: Reusing existing group at 9258000
Jan 1 12:35:50.635442 bgp_group_reuse: Has peer 10.0.0.1 (deleted)
Jan 1 12:35:50.635622 bgp_conf_peer_add: Reusing existing peer for 10.0.0.1
Jan 1 12:35:50.643870 task_timer_uset: timer BGP_RT_Background_BGP Route statistics timer <Touched> set to interval 30 at 12:36:20
Jan 1 12:35:50.644008 bgp_rt_update_med_igp_init: Deleting MED IGP update timer
Jan 1 12:35:50.644109 10.0.0.1 (Internal AS 65000): import eval flag set (config change)
Jan 1 12:35:50.646332 init BGP commit sync

Jan 1 12:35:50.646626 begin import processing
Jan 1 12:35:50.646714 task_job_create_background: create prio 5 job BGP reconfig for task BGP_Listen.0.0.0.0+179
Jan 1 12:35:50.648327 background dispatch running job BGP reconfig for task BGP_Listen.0.0.0.0+179
Jan 1 12:35:50.648481 Into post reconfig
Jan 1 12:35:50.648586 task_job_delete: delete background job BGP reconfig for task BGP_Listen.0.0.0.0+179
Jan 1 12:35:50.648655 background dispatch completed job BGP reconfig for task BGP_Listen.0.0.0.0+179
Jan 1 12:35:50.665837 rt_flash_update_callback: flash BGP_Group_iBGP (inet.0) start
Jan 1 12:35:50.673046 rt_flash_update_callback: flash BGP_Group_iBGP (inet.0) done
Jan 1 12:35:52.255410 bgp_keepalive_timeout: peer 10.0.0.1 (Internal AS 65000) last checked 76 last recv'd 28 last sent 29 last keepalive 29
Jan 1 12:35:52.255639 bgp_send: sending 19 bytes to 10.0.0.1 (Internal AS 65000)
Jan 1 12:35:52.255711 
Jan 1 12:35:52.255711 BGP SEND 10.0.0.2+179 -> 10.0.0.1+58090
Jan 1 12:35:52.255861 BGP SEND message type 4 (KeepAlive) length 19
Jan 1 12:35:59.759240 bgp_hold_timeout: peer 10.0.0.1 (Internal AS 65000) last checked 84 last recv'd 36 last sent 8 last keepalive 8
Jan 1 12:35:59.759566 task_timer_reset: reset BGP_65000.10.0.0.1+58090_Hold
Jan 1 12:35:59.759649 task_timer_set_oneshot_latest: timer BGP_65000.10.0.0.1+58090_Hold interval set to 54
Jan 1 12:36:07.746049 bgp_reuse_scan: Starting scan
Jan 1 12:36:19.538128 bgp_keepalive_timeout: peer 10.0.0.1 (Internal AS 65000) last checked 19 last recv'd 55 last sent 27 last keepalive 27
Jan 1 12:36:19.538373 bgp_send: sending 19 bytes to 10.0.0.1 (Internal AS 65000)
Jan 1 12:36:19.538443 
Jan 1 12:36:19.538443 BGP SEND 10.0.0.2+179 -> 10.0.0.1+58090
Jan 1 12:36:19.538529 BGP SEND message type 4 (KeepAlive) length 19
Jan 1 12:36:27.625836 bgp_reuse_scan: Starting scan
Jan 1 12:36:46.572878 bgp_keepalive_timeout: peer 10.0.0.1 (Internal AS 65000) last checked 46 last recv'd 82 last sent 27 last keepalive 27
Jan 1 12:36:46.573106 bgp_send: sending 19 bytes to 10.0.0.1 (Internal AS 65000)
Jan 1 12:36:46.573176 
Jan 1 12:36:46.573176 BGP SEND 10.0.0.2+179 -> 10.0.0.1+58090
Jan 1 12:36:46.573263 BGP SEND message type 4 (KeepAlive) length 19
Jan 1 12:36:47.621700 bgp_reuse_scan: Starting scan
Jan 1 12:36:53.759748 bgp_hold_timeout: peer 10.0.0.1 (Internal AS 65000) last checked 54 last recv'd 90 last sent 8 last keepalive 8
Jan 1 12:36:53.761462 bgp_hold_timeout:4032: NOTIFICATION sent to 10.0.0.1 (Internal AS 65000): code 4 (Hold Timer Expired Error), Reason: holdtime expired for 10.0.0.1 (Internal AS 65000), socket buffer sndcc: 57 rcvcc: 0 TCP state: 4, snd_una: 1400263074 snd_nxt: 1400263112 snd_wnd: 16921 rcv_nxt: 4258156560 rcv_adv: 4258172944, hold timer out 90s, hold timer remain 0s
Jan 1 12:36:53.761566 bgp_send: sending 21 bytes to 10.0.0.1 (Internal AS 65000)
Jan 1 12:36:53.761654 
Jan 1 12:36:53.761654 BGP SEND 10.0.0.2+179 -> 10.0.0.1+58090
Jan 1 12:36:53.761803 BGP SEND message type 3 (Notification) length 21
Jan 1 12:36:53.762161 BGP SEND Notification code 4 (Hold Timer Expired Error) subcode 0 (unused)
Jan 1 12:36:53.762303 bgp_peer_close: closing peer 10.0.0.1 (Internal AS 65000), state is 7 (Established)
Jan 1 12:36:53.762415 bgp_event: peer 10.0.0.1 (Internal AS 65000) old state Established event HoldTime new state Idle
Jan 1 12:36:53.763166 bgp_close_socket: peer 10.0.0.1 (Internal AS 65000)
Jan 1 12:36:53.763273 task_close: close socket 34 task BGP_65000.10.0.0.1+58090
Jan 1 12:36:53.763334 task_reset_socket: task BGP_65000.10.0.0.1+58090 socket 34
Jan 1 12:36:53.766525 task_timer_delete: BGP_65000.10.0.0.1_Keepalive <Latest>
Jan 1 12:36:53.766697 task_timer_delete: BGP_65000.10.0.0.1_Hold <Processing>
Jan 1 12:36:53.766941 task_job_create_background: create prio 4 job BGP closing job for task BGP_RT_Background
Jan 1 12:36:53.767928 background dispatch running job BGP closing job for task BGP_RT_Background
Jan 1 12:36:53.768291 bgp_reset_flash: resetting flash/new policy routes for BGP_Group_iBGP
Jan 1 12:36:53.768378 bgp_rtbit_free: Clearing bit 0x10000
Jan 1 12:36:53.768508 (add-path) Reseting ADDPATH bits set for peer 10.0.0.1 (Internal AS 65000), (bit: 0)
Jan 1 12:36:53.768610 bgp_event: peer 10.0.0.1 (Internal AS 65000) old state Idle event Start new state Active
Jan 1 12:36:53.768695 task_timer_ucreate: created timer BGP_65000.10.0.0.1_Connect flags <>
Jan 1 12:36:53.768795 task_timer_uset: timer BGP_65000.10.0.0.1_Connect <Touched> set to offset 32 at 12:37:25
Jan 1 12:36:53.768860 task_job_delete: delete background job BGP closing job for task BGP_RT_Background
Jan 1 12:36:53.768953 background dispatch completed job BGP closing job for task BGP_RT_Background
Jan 1 12:37:07.554566 bgp_reuse_scan: Starting scan

lab@jnpr1# run show system connections | match .179 
Active Internet connections (including servers)
Proto Recv-Q Send-Q Local Address Foreign Address (state) 
tcp4 0 78 10.0.0.2.179 10.0.0.1.58090 FIN_WAIT_1
tcp4 0 78 10.0.0.1.58090 10.0.0.2.179 FIN_WAIT_1
tcp46 0 0 *.179 *.* LISTEN
tcp4 0 0 *.179 *.* LISTEN
tcp46 0 0 *.179 *.* LISTEN
tcp4 0 0 *.179 *.* LISTEN