Find out the DNS server for a DHCP connection in Linux
Usually dhclient.leases file is located at
/var/lib/dhcp3/dhclient.leases, type the following command:
You can just use grep command to get DHCP server address, enter:
grep dhcp-server-identifier /var/lib/dhcp3/dhclient.leases
I recently had this problem where my
dhcpcd was misconfigured as was not setting DNS servers. I found out that I can query which nameservers are available by DHCP with the following command:
sudo dhcpcd -o domain_name_servers -T
The command will output a bunch of network connection information. Look for the line beginning with
From here I was able to manually set the nameservers.
I found my DHCP lease info at
/var/lib/dhclient/dhclient-eth0.leases in case anyone can't find it at
well, why not simply dig that?
[email protected] ~ $ dig google.de ; <<>> DiG 9.4.3-P3 <<>> google.de ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27579 ;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 6, ADDITIONAL: 0 ;; QUESTION SECTION: ;google.de. IN A ;; ANSWER SECTION: google.de. 1785 IN A 220.127.116.11 google.de. 1785 IN A 18.104.22.168 google.de. 1785 IN A 22.214.171.124 ;; AUTHORITY SECTION: de. 23431 IN NS L.DE.NET. de. 23431 IN NS Z.NIC.de. de. 23431 IN NS F.NIC.de. de. 23431 IN NS C.DE.NET. de. 23431 IN NS S.DE.NET. de. 23431 IN NS A.NIC.de. ;; Query time: 1 msec ;; SERVER: 192.168.1.15#53(192.168.1.15) ;; WHEN: Thu Sep 17 19:33:39 2009 ;; MSG SIZE rcvd: 181
look at the last lines: ;; SERVER: 192.168.1.15#53(192.168.1.15)