Ubuntu – Cannot resolve dns on 12.10 install

12.10dnsnetworkingresolv.confwireless

I am very new to networking on Ubuntu so I have been struggling with this issue for several hours now. I am running a fresh install of Ubuntu 12.10 and I am unable to resolve DNS when using my wireless connection. I have followed many of the solutions I found through some Googling but still can't get it to work. I tried adding the Google name servers to /etc/resolv.conf but that didn't help. I also tried adding static name servers through the network manager and that was unsuccessful as well. I get the following when I enter ifcongig -a on the command line.

eth0      Link encap:Ethernet  HWaddr 00:26:2d:7f:ea:7c  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
          Interrupt:16 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:247 errors:0 dropped:0 overruns:0 frame:0
          TX packets:247 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:22898 (22.8 KB)  TX bytes:22898 (22.8 KB)

wlan0     Link encap:Ethernet  HWaddr 70:1a:04:e9:3a:4b  
          inet addr:10.0.0.28  Bcast:10.0.0.255  Mask:255.255.255.0
          inet6 addr: fe80::721a:4ff:fee9:3a4b/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:121 errors:0 dropped:0 overruns:0 frame:0
          TX packets:403 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:41374 (41.3 KB)  TX bytes:38438 (38.4 KB)

My /etc/resolv.conf currently looks like this:

nameserver 8.8.8.8
nameserver 8.8.4.4

And on doing dig google.com I get:

; <<>> DiG 9.8.1-P1 <<>> google.com
;; global options: +cmd
;; connection timed out; no servers could be reached

On ping -c 10 8.8.8.8, I get:

PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
From 10.0.0.28 icmp_seq=1 Destination Host Unreachable
From 10.0.0.28 icmp_seq=2 Destination Host Unreachable
From 10.0.0.28 icmp_seq=3 Destination Host Unreachable
From 10.0.0.28 icmp_seq=5 Destination Host Unreachable
From 10.0.0.28 icmp_seq=6 Destination Host Unreachable
From 10.0.0.28 icmp_seq=7 Destination Host Unreachable
From 10.0.0.28 icmp_seq=8 Destination Host Unreachable
From 10.0.0.28 icmp_seq=10 Destination Host Unreachable

--- 8.8.8.8 ping statistics ---
10 packets transmitted, 0 received, +8 errors, 100% packet loss, time 8999ms
pipe 4

Here is my output for sudo route -n:

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.0.0.1        0.0.0.0         UG    0      0        0 wlan0
10.0.0.0        0.0.0.0         255.255.255.0   U     9      0        0 wlan0
169.254.0.0     0.0.0.0         255.255.0.0     U     1000   0        0 wlan0

And my output for traceroute -n 8.8.8.8:

traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 60 byte packets
 1  10.0.0.28  1804.234 ms !H  1804.210 ms !H  1804.199 ms !H

I would also like to note that I am able to connect to the wireless network on my other devices and on my Windows installation on the same machine. I also am able to get on the web when I connect through ethernet.

I get this snippet for the wireless connection when I do ipconfig on my windows machine:

Wireless LAN adapter Wireless Network Connection:

Connection-specific DNS Suffix  . : hsd1.ma.comcast.net.
Description . . . . . . . . . . . : Atheros AR5B93 Wireless Network Adapter
Physical Address. . . . . . . . . : 70-1A-04-E9-3A-4B
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::b153:23b2:2384:d341%12(Preferred)
IPv4 Address. . . . . . . . . . . : 10.0.0.28(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : Thursday, May 09, 2013 1:50:10 PM
Lease Expires . . . . . . . . . . : Thursday, May 16, 2013 3:39:12 PM
Default Gateway . . . . . . . . . : 10.0.0.1
DHCP Server . . . . . . . . . . . : 10.0.0.1
DHCPv6 IAID . . . . . . . . . . . : 225450500
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-17-D9-81-3A-00-26-2D-7F-EA-7C

DNS Servers . . . . . . . . . . . : 75.75.75.75
                                   75.75.76.76
NetBIOS over Tcpip. . . . . . . . : Enabled

Any help would be greatly appreciated since this is really frustrating.

Best Answer

Your /etc/resolv.conf appears correct. This appears to be a network issue, not a DNS one.

Try taking your eth0 down (some of the GUI network managers prefer wired connections over wireless, and it may think you have a signal for some strange reason). The command to take it down would be "sudo ifdown eth0" and then try to dig google.com. Alternately, if Ubuntu took the ifdown scripts away (don't know whether they did or not) you can do "sudo ifconfig eth0 down".

If you want to bring it back up, just do "sudo ifup eth0" or "sudo ifconfig eth0 up".

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