When I unplug a FreeRTOS+TCP device from my LAN, ping will complain like this:
C:\users\hein>ping 192.168.2.114
Pinging 192.168.2.114 with 32 bytes of data:
Reply from 192.168.2.114: bytes=32 time<1ms TTL=64
Reply from 192.168.2.114: bytes=32 time<1ms TTL=64
Request timed out. // Unplugged the network cable here
Request timed out.
Request timed out.
Request timed out.
When your ping says that “Destination Host unreachable”, I think that you should inspect the network setup, and especially the routing.
I found a good explanation about ping here.
It is also worth checking if the the IP address 192.168.1.5 is unique in your LAN. A while ago there was a post with a similar complaint, saying that ping was answered only for a short while.
Please have a look here.