SysToSys

Do you know the most difficult part of the job of a network engineer? You are responsible for every issue related to networking in your company. Even though everything works fine, someone will come up with a complaint, and it is on our head to fix it.

While I was working as a network engineer trainee, I received a call from the development section. The manager on Duty in the development section was angry and said that the network was not working.

When I asked him about the issue, he said the Internet is just fine, but one of his teammates received an error while pinging to a device in his subnet.

His teammate received the Destination Host Unreachable reply while he tried to ping to another computer in his section.

The manager on Duty demanded an explanation for the Destination Host Unreachable. I explained to him the reasons to receive Destination Host Unreachable error messages with examples. If you have not seen this error message before, have a look at the screenshot attached below.




What Is The Reason to Receive Destination Host Unreachable Error Message?

If you want a one-sentence answer, look at the statement in the table.

Either there is no device with the IP Address you typed or your computer has a corrupted ARP table.

Let me explain with the example I showed above. When I sent Ping packets to the IP address 192.168.225.45 from my computer, it looked at the ARP table stored in my PC to fetch the MAC address associated with the destination IP Address.

You know the basic rule of network communication. You cannot send packets to an IP Address before finding the MAC address (Physical Address) of the destination device.

ARP table shows the MAC address of the devices assigned with the specific IP Address.

If you do not know this concept, there are tons of tutorials available about Address Resolution Protocol (ARP) on the Internet.

My computer could not find the ARP Address mapped to the IP Address 192.168.225.45 in the ARP table.

C:\systosys>ping 192.168.225.45

Pinging 192.168.225.45 with 32 bytes of data:
Reply from 192.168.225.47: Destination host unreachable.
Reply from 192.168.225.47: Destination host unreachable.
Reply from 192.168.225.47: Destination host unreachable.
Reply from 192.168.225.47: Destination host unreachable.

Ping statistics for 192.168.225.45:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

C:\systosys>Destination Host Unreachable

So it displayed Reply from 192.168.225.47: Destination host unreachable as the response.


How to Fix Destination Host Unreachable?
If you do not know how to fix the reply from the x.x.x.x destination host unreachable message, follow the instructions provided below.

• [1]Flush the ARP Cache
  
  The first step to troubleshoot the Reply from 192.168.225.47: Destination host unreachable error is by deleting all entries in the ARP table on your computer.
  
  • Open the Command Prompt as Administrator
    
    Type cmd on the Windows Search
    
    Right Click on the Command Prompt from the Search Window
    
    Click on the Run as Administrator option
    
    Type the following command and press enter.
    
    

    netsh interface ip delete arpcache

    
    Try ping the same IP address again and check for the issue.

• [2] Run a Traceroute
  
  If the problem persists, you should run a traceroute to pinpoint the problem location.
  
  • Open Command Prompt
    
    Type the following command and press the enter key.
    

    tracert 192.168.225.45

    Check the result to understand the reason for the Destination Host Unreachable message.
    
    
    
    Why do I receive the ping reply Destination Host Unreachable? The traceroute result shows there is no such destination device.

• [3] Disable the Firewall on your PC
  
  In my experience, some users said faulty Firewall settings caused the Destination Host Unreachable error. So, I suggest you turn off the firewall on your laptop and check for the issue.

• Check the Status of the Destination Device and Test the Connection
  
  If the destination device is in your reach, make sure the device is on. Make sure the network connection is fine.
  
  You may unplug and replug the network cable to verify the connection status.

How to Check if Destination a Host Unreachable Error is Resolved?

It is very simple. You need to ping the same IP Address.

If the error is at the side of the IP Address, you should try to ping a different IP Address or domain name.


For example, check the command below to test whether the Destination a Host Unreachable Error fixed or not.

ping www.systosys.com

Nice article.

What if the "Reply from xx.xx.xx.xx: Destination host unreachable" is a different IP address than the ping request I sent?

Sending a remote ping to a static IP coming back with a different number. My ISP tells me to factory default the router. (It is brand new ) Thanks.

I just solved this problem across part of a network in which half of the workstations would receive this error message when trying to PING the server, and half could successfully PING the server. In my case (after looking everywhere else first), this turned out to be a defective network switch!

@ JMCU

You mentioned you received "Reply from xx.xx.xx.xx: Destination host unreachable" from a different IP address. Can you tell me whether the x.x.x.x is a local IP address or a remote public IP address?