A full example of such an error message, potentially seen directly in the cli or in the output of a syslog, is shown here: DFE(rw)->ping 10.23.203.4
<165>Mar 17 08:02:50 10.23.203.6 Default[1.tNetTask]arptnew failed on a18e725
10.23.203.4 is alive
This message is produced by code in the third-party HOST IP stack. It indicates that the stack was creating an ARP entry when it discovered that creation of the entry would be inappropriate. Based on the host subnet mask and route configuration, the IP address in the entry being created should be associated with a gateway, external to the switch.
The host probably received an ARP directly from the IP Address in question due to incorrect configuration of the mask, gateway, or routes on the network in general - possibly on the device issuing the error message. Misconfiguration of the host port vlan egress is also suspect.
Investigate and correct the network misconfiguration.
The hex number in the error message represents the IP address of the entry being processed. For example, "