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I'm doing some embedded Linux work with an ARM board. The ARM board is set up to serve a hostname, and you should be able to type in a browser on a laptop (connected via a router):

http://pynq:9090

and get a response (the board is set up with web content). This works just fine on a Windows laptop (Chrome/Win10) but on my Ubuntu laptop (Chrome/16.04.4) I get a DNS error.

I can ping the ip address of the board from my Ubuntu laptop (192.168.2.99) so all the connectivity is there. But

ping pynq:9090

from my Ubuntu laptop results in

ping: unknown host pynq:9090

I've been googling all morning, but I'm not finding an answer. Thanks for any help!

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    You can't ping a port number. You'd have to ping pynq. In addition, you have to look into how the name is announced. Do the DHCP server on the net update the DNS server? Do the board supply WINS lookup? Or Zeroconf? – vidarlo Sep 23 '17 at 17:50
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Not sure about windows but you need to either run a DNS server, use some sort of network announcement such as Avahi - https://help.ubuntu.com/community/HowToZeroconf , configure your router, or edit /etc/hosts

sudo nano /etc/hosts

Add a line

pyng_ip_address pyng

See http://manpages.ubuntu.com/manpages/zesty/man5/hosts.5.html

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As has been noted you can't ping a port. If you just want to check to see if the port is open, you can use

nmap -p 9090 IPADDRESS Where IPADDRESS is the IP of pyng. If the port is open then the system name pyng is unrecognized in which case this is the answer you need.

nmap is an extremely powerful networking tool. You may wish to peruse man netmap to get an idea of the scope.

if nmap isn't installed you can install it with the command sudo apt-get install nmap

If the ARM board is "Set to serve a hostname", you might check what DNS server your windows system is using and/or compare hosts files between the machines to get down to why this issue is occurring.

Sources:

https://serverfault.com/questions/309357/ping-a-specific-port

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Thank you for all the answers and information. I had a few things going on and they were all due to me only half knowing what the heck I was doing. Like I said, this all worked on my windows machine. So when I pinged my little embedded Linux target board from my windows machine, it came back with a "reply from" and an IP address I didn't recognize. Turns out I was using the wrong IP address for my board. Once I had the correct IP address I added that and the hostname to /etc/hosts and it all works. \

Thanks again!

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