Ubuntu can't access internet anymore.

[emptycoder]

Hello everyone, everything was working fine until this morning, I can no longer access Internet unless I connect a VPN, I think it's a DNS problem but I really don't know what to do to solve this problem.

[Iowan]

Have you tried pinging "somewhere" by name and/or address (eg. google.com or 8.8.8.8) to see if it's DNS related?
Routing is another possibility.

[emptycoder]

I already tried that, here is the output:
ping google.com
ping: unknown host google.com

But the strange thing that pingin 8.8.8.8 is fine!?
ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_req=1 ttl=48 time=127 ms
64 bytes from 8.8.8.8: icmp_req=2 ttl=48 time=135 ms
64 bytes from 8.8.8.8: icmp_req=3 ttl=48 time=133 ms

[rahul4557]

Change your DNS to 8.8.8.8 and then check..

Good Luck..

[steeldriver]

That's exactly what you'd expect when DNS isn't working - can you post the outputs of

cat /etc/resolv.conf

sudo lsof -i :53

as well please

[emptycoder]

Change your DNS to 8.8.8.8 and then check..

Good Luck..

I tried that already, in Network Manager - IPv4 Settings - Method: Automatic (DHCP) addresses only and set DNS servers to 8.8.8.8, 8.8.4.4

[emptycoder]

That's exactly what you'd expect when DNS isn't working - can you post the outputs of

cat /etc/resolv.conf

sudo lsof -i :53

as well please

Sure!
cat /etc/resolv.conf

# Generated by NetworkManager
nameserver 127.0.0.1

sudo lsof -i :53

COMMAND  PID   USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
dnsmasq 1333 nobody    4w  IPv4  11789      0t0  UDP localhost:domain 
dnsmasq 1333 nobody    5u  IPv4  11790      0t0  TCP localhost:domain (LISTEN)

I'm sorry for late replays, I have to disconnect my VPN to enter those codes then reconnect again to post in the forum.

[emptycoder]

Update:
Pinging 74.125.224.36 (Google IP) is fine but pinging google.com itself doesn't work (Not only Google, but every website)

[rahul4557]

can try making the following changes to interfaces file in /etc/network and then restart the networking service..

# The primary network interface
auto eth0
iface eth0 inet static
address *.*.*.* #your machine IP
gateway *.*.*.* #your ISP Gateway
network *.*.*.*
broadcast *.*.*.*
dns-nameservers 8.8.8.8 8.8.4.4 #dns servers

[emptycoder]

can try making the following changes to interfaces file in /etc/network and then restart the networking service..

I checked my router's settings the Gateway was blank.
I just don't understand why only IPs work instead of Domain names, everything was fine last night (sigh)
I remember I had this problem once before a long time ago and I found this workaround that fixed my problem:

sudo apt-get remove --purge resolvconf 
sudo /etc/init.d/networking restart

But I tried those commands and it didn't work, I remember they worked before but now nothing happens.