LAN strange ping response

[ivanka_busta]

Hi,

I have encountered a strange behaviour in a network and I'm not sure what's happening. I think it looks like a duplicate IP but I'm not sure.

I'm located in the company headquarters, when I ping the devices (PCs, switches, routers...) located in one of the branches the first response is always a  host unreachable from an IP assigned to a PC, then the next  three ping responses are correct:

ping 192.168.53.246

Respuesta desde 192.168.53.10: Host de destino inaccesible.
Respuesta desde 192.168.53.246: bytes=32 tiempo=3ms TTL=58
Respuesta desde 192.168.53.246: bytes=32 tiempo=3ms TTL=58
Respuesta desde 192.168.53.246: bytes=32 tiempo=3ms TTL=58

Issuing ping 192.168.53.10 I found the switch port where the device using that IP is located. If I shutdown the port I can't get a ping response to 192.168.53.10 from the switch. However, from my PC located in the headquarters there is response. Does this mean that there are two devices with the same IP? 

I don't understand why when I issue a ping to any of the IPs of the devices in the branch the first response it's always from 192.168.53.10. Does it mean that this ÏP is assigned to the router?

I've just checked that this problem doesn't happen in all the computers in the headquarters. There are PCs were you ping devices in the branch office and you don't get the response from 192.168.53.10.

Thanks. 

[Joseph W. Doherty]

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages wha2tsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

Often a first ping times out waiting for ARP resolution.

[ivanka_busta]

Hi,

Yes, but I don't understand why that first wrong response is coming from the IP of a PC which has nothing to do with the IP I'm trying to ping.

Thank you.

[Richard Bradfield]

Is there some App running on 192.168.53.10 that responds to requests? you say there is no problem if .10 is disconnected

[premkumarjm]

Hi,

192.168.53.10 - is that your local system IP or Gateway IP.

If no, have you tried the traceroute for 192.168.53.10? may be it will shows you some clear map about  the destination.

BR

Prem

[ivanka_busta]

Hi,

192.168.53.10 is a PC of the branch network.

When I did a traceroute I just get:

  1    <1 ms    <1 ms    <1 ms  [192.168.53.10]

Thank you.

[jamiebutterworth2016]

That's odd. I've not come across that before myself.

Please could you do ipconfig and tell us the ip address of the host you're pinging from? Just to confirm it's not the local box.

If snmp is allowed on your network, you could use spiceworks network monitor to find out what .10 is.

[premkumarjm · Accepted solution]

Hi, 

Hope, that may be your secondary ip, which is same as your branch network. Go to network settings in the pc you have been trying and check is there any secondary ip has been configured in ur machine.

BR

Prem

[ivanka_busta]

Hi,

Yes, 192.168.53.10 was configured on the wireless card of the computer. I disabled the wireless card and now I can ping correctly to every device in 192.168.53.0/24

Thank you.