Networking qnx to xp

I am new to QNX and havnt really dealt with networking in the past. I am trying to network two computers, one running windows xp and the
other running QNX neutrino 6.4.1.

The xp side has a manually configured IP address ( for a LAN connection and I am trying to get the QNX machine to connect. I have assigned it a similar IP ( and netmask and enabled the connection. I have a crossover LAN connection between the two. I try testing it by pinging from both ends, however I only get data back when pinging from the xp machine.

I am wondering if you know of any obvious reasons as to why this would
occur. I have been playing around with different things all day, as I think it could be a firewall issue, but to no avail.

Any ideas would be appreciated.


Did you by chance specify a nameserver on your QNX machine when you set up the network?

If you do that, a ping command will always try and contact the namesever even if you manually specify an IP address. Because it’s not there you have t to wait 45 seconds for the timeout before the ping command will start returning data.

For that reason I always turn off a nameserver unless I have one available.

Also on some Windows machines the default network option is to block ICMP (ping) requests. If that’s enabled on your XP machine it won’t respond to pings.

Other things to try that you didn’t mention is can you:

  1. Ping (on the QNX machine. This is the loop back address)
  2. (on the QNX machine. Ping yourself)
  3. (on the windows machine. Ping yourself)


Yes and if your XP has a firewall, it could turn of Ping to try to make it more invisible.

Thanks for the replies guys!

I had turned on ICMP requests on the windows firewall, but not on the two others that were running apparently.
I have no idea why the computer had three firewalls nor why they were all on. Upon disabling the windows one, uninstalling another and enabling ICMP on the final one I can now ping from both machines and recieve all packets!

Pinging myself from XP would have been a good idea I think.