Hello,

Our System state: 

FreeBSD M3CTESTLABO-SAG01 12.1-RELEASE-p1 FreeBSD 12.1-RELEASE-p1 GENERIC  amd64

Following Problem:

if we disconnect the LAN cable or shutdown the switchport, the system does not logging the information about link state change e.g. Links igb0 goes down (IFNET igb0 LINK_DOWN)

on the interface the state does not change into no carrier 

igb0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
  description: PUBLIC
  options=e527bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,TSO6,LRO,WOL_MAGIC,VLAN_HWFILTER,VLAN_HWTSO,RXCSUM_IPV6,TXCSUM_IPV6>
  ether ac:1f:6b:1a:88:ba
  inet XXX.XXX.XXX.XXX netmask 0xffffff00 broadcast XXX.XXX.XXX.XXX
  media: Ethernet autoselect (1000baseT <full-duplex>)
  status: active
  nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>


in this situation it isn't possible to track the changes from the Link with devd to handle something like e.g.

notify 0 {
 match "system"        "IFNET";
 match "subsystem"         "(igb0)";
 match "type"        "LINK_DOWN";
 action "logger $subsystem is DOWN by devd";
};

notify 0 {
 match "system"        "IFNET";
 match "subsystem"         "(igb0)";
 match "type"        "LINK_UP";
 action "logger $subsystem is UP by devd";
};


Network Adapter:

<Intel(R) PRO/1000 PCI-Express Network Driver> port 0xe000-0xe01f mem 0xdf400000-0xdf47ffff,0xdf480000-0xdf483fff irq 16 at device 0.0 on pci1


If you need more information, please let me know

Regards
Toto