D-Link DGS-1510 Series Reference Manual page 127

DGS-1510 Series Gigabit Ethernet SmartPro Switch CLI Reference Guide
Type
State
D – Dynamic learning entry.
S – Static neighbor entry.
INCMP: (Incomplete) Address resolution is being performed on the
entry, but the corresponding neighbor advertisement message has
not yet been received.
REACH: (Reachable) Corresponding neighbor advertisement
message was received and the reachable time (in milliseconds) has
not elapsed yet. It indicates that the neighbor was functioning
properly.
STALE: More than the reachable time (in milliseconds) have
elapsed since the last confirmation was received.
PROBE - Sending the neighbor solicitation message to confirm the
reachability.
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