DNS issues on Ubuntu 12.04 with OpenVPN

Question

I followed this guide to setup openvpn on my home network.

I accidentally downloaded ubuntu 12.10 at first and without noticing, I went ahead and followed the guide...

Then I did some stuff from here: push "redirect-gateway def1" iptables -t nat -A POSTROUTING -s 10.8.0.0/24 -o eth0 -j MASQUERADE

to enable browsing.

OpenVPN was fully function.

By that I mean, I was able to remote in (access internal services) and mask my IP when browsing from the outside.

Then I realized that I wanted ubuntu 12.04 so I followed the same process on a new install.

Now the problem is that the DNS does not resolve.

I noticed that downloading openvpn downloaded resolvconf which I uninstalled and attempted to go about this manually.

Here is some stuff from my system:

openvpn server.conf:

mode server
tls-server

local 192.168.1.101 ## ip/hostname of server
port 80 ## default openvpn port
proto udp

#bridging directive
dev tap0 ## If you need multiple tap devices, add them here
up "/etc/openvpn/up.sh br0 tap0 1500"
down "/etc/openvpn/down.sh br0 tap0"

persist-key
persist-tun

#certificates and encryption
ca ca.crt
cert server.crt
key server.key  # This file should be kept secret
dh dh1024.pem
tls-auth ta.key 0 # This file is secret

cipher BF-CBC        # Blowfish (default)
comp-lzo

#DHCP Information
ifconfig-pool-persist ipp.txt
server-bridge 192.168.1.10 255.255.255.0 192.168.1.100 192.168.1.110
push "redirect-gateway def1"
push "dhcp-option DNS 8.8.8.8"
push "dhcp-option DNS 8.8.4.4"


#push "dhcp-option DOMAIN yourdomain.com"
#push "redirect-gateway local def1"
#push "dhcp-option DNS 8.8.8.8"
#push "redirect-gateway def1 bypass-dhcp"
#push "dhcp-option DNS 192.168.1.1"
#push "dhcp-option DNS 8.8.8.8"


max-clients 10 ## set this to the max number of clients that should be connected at a time

#log and security
user nobody
group nogroup
keepalive 10 120
status openvpn-status.log
verb 3

/etc/network/interfaces:

root@ironman:~# cat /etc/network/interfaces 
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
#auto lo
#iface lo inet loopback

# The primary network interface
#auto eth0
#iface eth0 inet dhcp
#############OPEN VPN SETUP###############
## This is the network bridge declaration

## Start these interfaces on boot
auto lo br0

iface lo inet loopback

iface br0 inet static 
  address 192.168.1.101 
  netmask 255.255.255.0
  gateway 192.168.1.1
  bridge_ports eth0
  nameserver 8.8.8.8
iface eth0 inet manual
  up ip link set $IFACE up promisc on
  down ip link set $IFACE down promisc off
  nameserver 8.8.8.8

root@ironman:~# cat /etc/resolv.conf 
nameserver 8.8.8.8
nameserver 192.168.1.1


root@ironman:~# ping google.com
PING google.com (74.125.239.100) 56(84) bytes of data.
64 bytes from nuq05s01-in-f4.1e100.net (74.125.239.100): icmp_req=1 ttl=55 time=22.6 ms
64 bytes from nuq05s01-in-f4.1e100.net (74.125.239.100): icmp_req=2 ttl=55 time=21.7 ms
64 bytes from nuq05s01-in-f4.1e100.net (74.125.239.100): icmp_req=3 ttl=55 time=22.8 ms

Any help would be appreciated

Solution 1

This works for me: http://www.softwarepassion.com/solving-dns-problems-with-openvpn-on-ubuntu-box/

The important step is adding following three lines into your client openvpn config file:

script-security 2
up /etc/openvpn/update-resolv-conf
down /etc/openvpn/update-resolv-conf

Also ensure the resolvconf package is installed on the client as this script depends on it.

It works with openvpn client service or command (sudo openvpn youropenvpn.conf).

However, the Ubuntu Network Manager doesn't work for this configuration. It's an issue so far: https://bugs.launchpad.net/ubuntu/+source/openvpn/+bug/1211110

Solution 2

When you re-installed 12.04 did you forget this step?

echo 1 > /proc/sys/net/ipv4/ip_forward

Source: https://openvpn.net/index.php/open-source/documentation/miscellaneous/88-1xhowto.html