Added "debug zebra events", "debug zebra kernel", and "log file /var/log/frr/debug.log" to frr.conf. This is a boot where the set-src directive was not loaded at startup.

var_log_frr_debug.log

2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWADDR(20), len=76, seq=1557163160, pid=607
2019/05/06 17:19:19 ZEBRA: netlink_interface_addr RTM_NEWADDR lo flags 0x80:
2019/05/06 17:19:19 ZEBRA:   IFA_LOCAL     10.66.66.10/32
2019/05/06 17:19:19 ZEBRA:   IFA_ADDRESS   10.66.66.10/32
2019/05/06 17:19:19 ZEBRA:   IFA_CACHEINFO pref -1, valid -1
2019/05/06 17:19:19 ZEBRA: MESSAGE: ZEBRA_INTERFACE_ADDRESS_ADD 10.66.66.10/32 on lo(0)
2019/05/06 17:19:19 ZEBRA: rib_update : AFI_IP event 0
2019/05/06 17:19:19 ZEBRA: rib_update : AFI_IP6 event 0
2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWROUTE(24), len=60, seq=0, pid=0
2019/05/06 17:19:19 ZEBRA: RTM_NEWROUTE ipv4  proto kernel NS 0
2019/05/06 17:19:19 ZEBRA: zebra message comes from socket [23]
2019/05/06 17:19:19 ZEBRA: zebra message comes from socket [23]
2019/05/06 17:19:19 ZEBRA: zebra message comes from socket [23]
2019/05/06 17:19:19 ZEBRA: zebra message comes from socket [23]
2019/05/06 17:19:19 ZEBRA: client 23 says hello and bids fair to announce only ospf routes vrf=0
2019/05/06 17:19:19 ZEBRA: bfd_client_register msg from client ospf: length=4
2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWLINK(16), len=1248, seq=0, pid=0
2019/05/06 17:19:19 ZEBRA: RTM_NEWLINK update for ens18(2) sl_type 0 master 0 flags 0x11043
2019/05/06 17:19:19 ZEBRA: Intf ens18(2) has come UP
2019/05/06 17:19:19 ZEBRA: MESSAGE: ZEBRA_INTERFACE_UP ens18(0)
2019/05/06 17:19:19 ZEBRA: rib_update : AFI_IP event 0
2019/05/06 17:19:19 ZEBRA: rib_update : AFI_IP6 event 0
2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWROUTE(24), len=116, seq=0, pid=0
2019/05/06 17:19:19 ZEBRA: RTM_NEWROUTE ipv6 unicast proto boot NS 0
2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWROUTE(24), len=116, seq=0, pid=0
2019/05/06 17:19:19 ZEBRA: RTM_NEWROUTE ipv6 unicast proto kernel NS 0
2019/05/06 17:19:19 OSPF: EXT (ospf_ext_pref_ism_change): Set Node SID to interface lo 
2019/05/06 17:19:19 ZEBRA: zebra message comes from socket [23]
2019/05/06 17:19:19 ZEBRA: zebra message comes from socket [28]
2019/05/06 17:19:19 ZEBRA: zebra message comes from socket [28]
2019/05/06 17:19:19 ZEBRA: zebra message comes from socket [28]
2019/05/06 17:19:19 ZEBRA: client 28 says hello and bids fair to announce only static routes vrf=0
2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWADDR(20), len=80, seq=1557163160, pid=635
2019/05/06 17:19:19 ZEBRA: netlink_interface_addr RTM_NEWADDR ens18 flags 0x80:
2019/05/06 17:19:19 ZEBRA:   IFA_LOCAL     10.66.20.125/29
2019/05/06 17:19:19 ZEBRA:   IFA_ADDRESS   10.66.20.125/29
2019/05/06 17:19:19 ZEBRA:   IFA_CACHEINFO pref -1, valid -1
2019/05/06 17:19:19 ZEBRA: MESSAGE: ZEBRA_INTERFACE_ADDRESS_ADD 10.66.20.125/29 on ens18(0)
2019/05/06 17:19:19 ZEBRA: rib_update : AFI_IP event 0
2019/05/06 17:19:19 ZEBRA: rib_update : AFI_IP6 event 0
2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWROUTE(24), len=60, seq=0, pid=0
2019/05/06 17:19:19 ZEBRA: RTM_NEWROUTE ipv4  proto kernel NS 0
2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWROUTE(24), len=60, seq=0, pid=0
2019/05/06 17:19:19 ZEBRA: RTM_NEWROUTE ipv4 unicast proto kernel NS 0
2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWROUTE(24), len=60, seq=0, pid=0
2019/05/06 17:19:19 ZEBRA: RTM_NEWROUTE ipv4  proto kernel NS 0
2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWROUTE(24), len=60, seq=0, pid=0
2019/05/06 17:19:19 ZEBRA: RTM_NEWROUTE ipv4  proto kernel NS 0
2019/05/06 17:19:19 OSPF: EXT (ospf_ext_link_ism_change): Set Adj. SID to interface ens18 
2019/05/06 17:19:19 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWNEIGH(28), len=76, seq=0, pid=0
2019/05/06 17:19:19 ZEBRA: zebra message comes from socket [23]
2019/05/06 17:19:20 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWADDR(20), len=72, seq=0, pid=0
2019/05/06 17:19:20 ZEBRA: netlink_interface_addr RTM_NEWADDR ens18 flags 0x80:
2019/05/06 17:19:20 ZEBRA:   IFA_ADDRESS   fe80::10e0:bbff:fe6e:454b/64
2019/05/06 17:19:20 ZEBRA:   IFA_CACHEINFO pref -1, valid -1
2019/05/06 17:19:20 ZEBRA: MESSAGE: ZEBRA_INTERFACE_ADDRESS_ADD fe80::10e0:bbff:fe6e:454b/64 on ens18(0)
2019/05/06 17:19:20 ZEBRA: rib_update : AFI_IP event 0
2019/05/06 17:19:20 ZEBRA: rib_update : AFI_IP6 event 0
2019/05/06 17:19:20 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWROUTE(24), len=116, seq=0, pid=0
2019/05/06 17:19:20 ZEBRA: RTM_NEWROUTE ipv6  proto  NS 0
2019/05/06 17:19:24 ZEBRA: Event driven route-map update triggered
2019/05/06 17:19:24 ZEBRA: Event handler for route-map: set_src_addr
2019/05/06 17:19:24 ZEBRA: zebra_rib_table_rm_update : AFI_IP rmap set_src_addr, route type ospf
2019/05/06 17:19:24 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWNEIGH(28), len=76, seq=0, pid=0
2019/05/06 17:19:24 ZEBRA: netlink_parse_info: netlink-listen (NS 0) type RTM_NEWNEIGH(28), len=76, seq=0, pid=0
2019/05/06 17:19:29 OSPF: DR-Election[1st]: Backup 10.66.20.125
2019/05/06 17:19:29 OSPF: DR-Election[1st]: DR     10.66.20.126
2019/05/06 17:19:29 OSPF: DR-Election[2nd]: Backup 10.66.20.125
2019/05/06 17:19:29 OSPF: DR-Election[2nd]: DR     10.66.20.126
2019/05/06 17:19:29 OSPF: interface 10.66.20.125 [2] join AllDRouters Multicast group.
2019/05/06 17:19:29 OSPF: EXT (ospf_ext_link_ism_change): Set Adj. SID to interface ens18 
2019/05/06 17:19:29 OSPF: DR-Election[1st]: Backup 10.66.20.125
2019/05/06 17:19:29 OSPF: DR-Election[1st]: DR     10.66.20.126
2019/05/06 17:19:29 ZEBRA: zebra message comes from socket [23]
2019/05/06 17:19:29 ZEBRA: zebra message comes from socket [23]
2019/05/06 17:19:37 STATIC: Terminating on signal
2019/05/06 17:19:37 ZEBRA: connection closed socket [28]
2019/05/06 17:19:37 ZEBRA: [EC 4043309117] Client 'static' encountered an error and is shutting down.
2019/05/06 17:19:37 ZEBRA: Closing client 'static'
2019/05/06 17:19:37 ZEBRA: release_daemon_table_chunks: Released 0 table chunks
2019/05/06 17:19:37 ZEBRA: release_daemon_label_chunks: Released 0 label chunks
2019/05/06 17:19:37 ZEBRA: client 28 disconnected. 0 static routes removed from the rib
2019/05/06 17:19:37 ZEBRA: Terminating on signal
2019/05/06 17:19:37 ZEBRA: Closing client 'ospf'
2019/05/06 17:19:37 ZEBRA: release_daemon_table_chunks: Released 0 table chunks
2019/05/06 17:19:37 ZEBRA: release_daemon_label_chunks: Released 0 label chunks
2019/05/06 17:19:37 ZEBRA: client 23 disconnected. 2 ospf routes removed from the rib
2019/05/06 17:19:37 ZEBRA: VRF default id 0 is now inactive
2019/05/06 17:19:37 ZEBRA: MESSAGE: ZEBRA_VRF_DELETE default
2019/05/06 17:19:37 ZEBRA: VRF default id 0 deleted
2019/05/06 17:19:37 ZEBRA: Zebra final shutdown
2019/05/06 17:19:37 OSPF: Terminating on signal
2019/05/06 17:19:37 OSPF: ASBR[Status:255]: Update
2019/05/06 17:19:37 OSPF: EXT (ospf_ext_pref_ism_change): Set Node SID to interface lo 
2019/05/06 17:19:37 OSPF: DR-Election[1st]: Backup 10.66.20.125
2019/05/06 17:19:37 OSPF: DR-Election[1st]: DR     10.66.20.125
2019/05/06 17:19:37 OSPF: DR-Election[2nd]: Backup 0.0.0.0
2019/05/06 17:19:37 OSPF: DR-Election[2nd]: DR     10.66.20.125
2019/05/06 17:19:37 OSPF: EXT (ospf_ext_link_ism_change): Set LAN Adj. SID to interface ens18 
2019/05/06 17:19:37 OSPF: interface 10.66.20.125 [2] leave AllDRouters Multicast group.
2019/05/06 17:19:37 OSPF: EXT (ospf_ext_link_ism_change): Set Adj. SID to interface ens18