What does incomplete mean in an ARP entry

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If the value of MAC ADDRESS in an ARP entry is Incomplete, this ARP entry is a temporary one. When IP packets trigger ARP Miss messages, the device generates temporary ARP entries and sends ARP Request packets to the destination network segment.
When a temporary ARP entry is not aged out:
Before receiving an ARP Reply packet, the device discards the IP packets matching the temporary ARP entry, and no ARP Miss message is triggered.
After receiving the ARP Reply packet, the device generates a correct ARP entry to replace the temporary entry.
After the temporary ARP entry ages out, the device deletes this entry.

Other related questions:
Preventing ARP entries of the incomplete type on a device
Configure a blackhole route or security policy for the related NAT address pool to discard the packets destined for the addresses in the address pool.

Why does an ARP entry not contain VLAN information
If an ARP entry does not contain VLAN information, the entry contains information about a Layer 3 interface. If an ARP entry contains VLAN information and the interface in the entry is not a sub-interface, the entry contains information about a Layer 2 interface. Run the display arp command to view ARP entries. For example, the ARP entries in V100R003C00 are as follows: - When an ARP entry contains VLAN information, a VLAN ID is displayed in the VLAN field in the command output. - The ARP entry of which the IP address is 10.1.1.2 and the MAC address is 04f9-388d-e685 is dynamically learned from 10GE1/0/3, the VLAN ID is 101, and the remaining lifetime of the entry is 5 minutes. - The ARP entry of which the IP address is 10.1.1.3 and the MAC address is 0023-0045-0067 is a static entry, the outbound interface is 10GE1/0/3, and the VLAN ID is 101. display arp network 10.1.1.0 24 ARP Entry Types: D - Dynamic, S - Static, I - Interface EXP: Expire-time IP ADDRESS MAC ADDRESS EXP(M) TYPE/VLAN INTERFACE VPN-INSTANCE ------------------------------------------------------------------------------ 10.1.1.3 0023-0045-0067 S/101 10GE1/0/3 10.1.1.1 306b-2079-2205 I Vlanif101 10.1.1.2 04f9-388d-e685 5 D/101 10GE1/0/3 ------------------------------------------------------------------------------ Total:3 Dynamic:1 Static:1 Interface:1 - When only the ARP entry type is displayed in the TYPE/VLAN field, the ARP entry does not contain VLAN information. ARP Entry Types: D - Dynamic, S - Static, I - Interface EXP: Expire-time IP ADDRESS MAC ADDRESS EXP(M) TYPE/VLAN INTERFACE VPN-INSTANCE ------------------------------------------------------------------------------ 172.16.1.3 0023-0045-0069 S 10GE1/0/13 172.16.1.1 306b-2079-2202 I 10GE1/0/13 172.16.1.2 0025-9e95-7c32 3 D 10GE1/0/13 ------------------------------------------------------------------------------ Total:3 Dynamic:1 Static:1 Interface:1

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