Well, a Linux based router sends ICMP host unreachable in this exact same configuration. The Linux router sends ARP requests on the destination network, stops after 3 seconds and sends back an ICMP host unreachable. With the same architecture, the Cisco sends the ARP requests, and that's all.
Apr 25, 2013 What is the Destination Port Unreachable Error Message ICMP requests do not use a port number, but both TCP and UDP packets use port numbers. Theoretically, Port Unreachable message comes with UDP and TCP connection failure. Destination Port unreachable reply should not from ICMP echo requests. Other Important ICMP Replies . PING: Transmit failed. General Failure; Ping Request Could Not Find Host. Internet Control Message Protocol (ICMP) Parameters
The ICMP destination unreachable message is generated by a router to inform the source host that the destination unicast address is unreachable. The IP header plus the first 8 bytes of the original datagram's data is returned to the sender.
icmp - Difference between ping timed out and destination The Reply from 192.168.2.120: Destination host unreachable. is after the destination MAC address has timed out of the source/router's ARP cache, and the source/router no longer has, or can get, a MAC address for the destination. Eventually, the destination comes back up, and it responds to the ARP request of the source/router, and your ping is How to Fix This Destination Host Unreachable May 01, 2020
Host Unreachable Select this check box to allow ICMP Host Unreachable messages. Your network usually sends these messages when it cannot use a host or service. Port Unreachable Select this check box to allow ICMP Port Unreachable messages. A host or firewall usually sends these messages when a network service is not available or is not allowed.
icmp - tcpdump host unreachables for specific host If I understand you correctly, you want to filter for z.z.z.z in the ICMP response. Let's assume the IP of the unreachable host is z1.z2.z3.z4, then you should replace host x.x.x.x in your filter with the following filter icmp[24] == z1 and icmp[25] == z2 and icmp[26] == z3 and icmp[27] == z4.. If you only want the ICMP destination unreachable messages, consider using icmp[icmptype] == icmp ICMP Destination Unreachable - Wireshark Q&A