Não é possível conectar-se à Internet usando uma placa Realtek Lan RTL8105TA

Question

Eu fiz um LiveUsb para o Elementary antes de instalá-lo no meu notebook. Tudo funciona bem, exceto pela internet. Eu não tenho WiFi, mas uma conexão com fio. Não consigo me conectar à internet de forma alguma. Minha placa Ethernet é uma RT-8510 da Realtek Lan.

elementary@elementary:~$ ifconfig
eth0      Link encap:Ethernet  HWaddr 04:7d:7b:9f:8a:72  
          inet addr:10.118.14.86  Bcast:10.118.255.255  Mask:255.255.0.0
          inet6 addr: fe80::67d:7bff:fe9f:8a72/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:21692 errors:0 dropped:8 overruns:0 frame:0
          TX packets:935 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1809988 (1.8 MB)  TX bytes:97546 (97.5 KB)
          Interrupt:44 Base address:0xe000 

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:1261 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1261 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:84217 (84.2 KB)  TX bytes:84217 (84.2 KB)

elementary@elementary:~$ cat /etc/network/interfaces
auto lo
iface lo inet loopback

elementary@elementary:~$ cat /etc/udev/rules.d/70-persistent-net.rules

elementary@elementary:~$ lspci -k | grep -A2i net ; nmcli d list
grep: 2i: invalid context length argument
GENERAL.DEVICE:                         wlan0
GENERAL.TYPE:                           802-11-wireless
GENERAL.VENDOR:                         Atheros Communications Inc.
GENERAL.PRODUCT:                        AR9462 Wireless Network Adapter
GENERAL.DRIVER:                         ath9k
GENERAL.HWADDR:                         08:ED:B9:79:C6:99
GENERAL.STATE:                          20 (unavailable)
GENERAL.REASON:                         0 (No reason given)
GENERAL.UDI:                            /sys/devices/pci0000:00/0000:00:05.0/0000:02:00.0/net/wlan0
GENERAL.IP-IFACE:
GENERAL.NM-MANAGED:                     yes
GENERAL.FIRMWARE-MISSING:               no
GENERAL.CONNECTION:                     not connected
CAPABILITIES.CARRIER-DETECT:            no
CAPABILITIES.SPEED:                     unknown
WIFI-PROPERTIES.WEP:                    yes
WIFI-PROPERTIES.WPA:                    yes
WIFI-PROPERTIES.WPA2:                   yes
WIFI-PROPERTIES.TKIP:                   yes
WIFI-PROPERTIES.CCMP:                   yes
GENERAL.DEVICE:                         eth0
GENERAL.TYPE:                           802-3-ethernet
GENERAL.VENDOR:                         Realtek Semiconductor Co., Ltd.
GENERAL.PRODUCT:                        RTL8101E/RTL8102E PCI Express Fast Ethernet controller
GENERAL.DRIVER:                         r8169
GENERAL.HWADDR:                         04:7D:7B:9F:8A:72
GENERAL.STATE:                          100 (connected)
GENERAL.REASON:                         0 (No reason given)
GENERAL.UDI:                            /sys/devices/pci0000:00/0000:00:04.0/0000:01:00.0/net/eth0
GENERAL.IP-IFACE:                       eth0
GENERAL.NM-MANAGED:                     yes
GENERAL.FIRMWARE-MISSING:               no
GENERAL.CONNECTION:                     /org/freedesktop/NetworkManager/ActiveConnection/5
CAPABILITIES.CARRIER-DETECT:            yes
CAPABILITIES.SPEED:                     100 Mb/s
WIRED-PROPERTIES.CARRIER:               on
IP4.ADDRESS[1]:                         ip = 10.118.14.86/16, gw = 10.118.0.1
IP4.DNS[1]:                             172.16.172.9
IP4.DNS[2]:                             172.16.172.10
DHCP4.OPTION[1]:                        expiry = 1416959395
DHCP4.OPTION[2]:                        broadcast_address = 10.118.255.255
DHCP4.OPTION[3]:                        dhcp_message_type = 5
DHCP4.OPTION[4]:                        routers = 10.118.0.1
DHCP4.OPTION[5]:                        dhcp_lease_time = 2592000
DHCP4.OPTION[6]:                        ip_address = 10.118.14.86
DHCP4.OPTION[7]:                        subnet_mask = 255.255.0.0
DHCP4.OPTION[8]:                        domain_name_servers = 172.16.172.9 172.16.172.10
DHCP4.OPTION[9]:                        ntp_servers = 192.43.244.18
DHCP4.OPTION[10]:                       network_number = 10.118.0.0
DHCP4.OPTION[11]:                       dhcp_server_identifier = 192.168.3.1