This case scenario is for a router with embedded linux, but I think the answer could be the same for any Linux system.
This is my DNS check:
~ $ cat /etc/resolv.conf nameserver 22.214.171.124 nameserver 126.96.36.199 ~ $ ping 188.8.131.52 PING 184.108.40.206 (220.127.116.11): 56 data bytes 64 bytes from 18.104.22.168: seq=0 ttl=250 time=50.0 ms 64 bytes from 22.214.171.124: seq=1 ttl=250 time=40.0 ms ^C --- 126.96.36.199 ping statistics --- 2 packets transmitted, 2 packets received, 0% packet loss round-trip min/avg/max = 40.0/45.0/50.0 ms ~ $ ping www.google.es PING www.google.es (2a00:1450:4007:808::101f): 56 data bytes ping: sendto: Network is unreachable ~ $ ping 188.8.131.52 PING 184.108.40.206 (220.127.116.11): 56 data bytes 64 bytes from 18.104.22.168: seq=0 ttl=57 time=50.0 ms 64 bytes from 22.214.171.124: seq=1 ttl=57 time=40.0 ms 64 bytes from 126.96.36.199: seq=2 ttl=57 time=40.0 ms ^C --- 188.8.131.52 ping statistics --- 3 packets transmitted, 3 packets received, 0% packet loss round-trip min/avg/max = 40.0/43.3/50.0 ms
As can be seen, there is a response from internet (
184.108.40.206) but not from domain names (
www.google.es, same for
The DNS server (
220.127.116.11) answers to pings.
So I was wondering if the problem could be in that DNS server.
Is there some way, like telneting or similar, to check if a given DNS IP works as it must (this is: answering with a IP address when requested for a domain name)?
For example, when testing a SSH server, a possible trick is:
C:\Users\Luis>telnet Midnighter- 22 SSH-2.0-OpenSSH_6.7p1 Debian-5
Third party tools accepted. Command line and Open source preferred.