Lan not working

Question

I am about to use a wimax modem and obtain internet connection through the ethernet cables but when the ISP installer(who came to our house not that familiar in Linux) is about to configure, he can't do it.

So I just tried these things out:

1)

Input:

ethtool eth0

Output:

    Supported ports: [ TP ]
    Supported link modes:   10baseT/Half 10baseT/Full 
                            100baseT/Half 100baseT/Full 
    Supported pause frame use: No
    Supports auto-negotiation: Yes
    Advertised link modes:  Not reported
    Advertised pause frame use: No
    Advertised auto-negotiation: Yes
    Speed: Unknown!
    Duplex: Unknown! (255)
    Port: Twisted Pair
    PHYAD: 0
    Transceiver: internal
    Auto-negotiation: on
    MDI-X: Unknown
Cannot get wake-on-lan settings: Operation not permitted
    Current message level: 0x0000003f (63)
                   drv probe link timer ifdown ifup
    Link detected: no

2)

Input:

ethtool ethX

Output:

Cannot get device settings: No such device
Cannot get wake-on-lan settings: No such device
Cannot get message level: No such device
Cannot get link status: No such device
No data available

3)

Input:

sudo rfkill list all

Output:

0: ideapad_wlan: Wireless LAN
    Soft blocked: no
    Hard blocked: yes
1: ideapad_bluetooth: Bluetooth
    Soft blocked: yes
    Hard blocked: yes
2: phy0: Wireless LAN
    Soft blocked: no
    Hard blocked: no
3: brcmwl-0: Wireless LAN
    Soft blocked: no
    Hard blocked: yes

4)

Input:

ifconfig -a

Ouptut:

eth0      Link encap:Ethernet  HWaddr b8:88:e3:88:62:3b  
          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)

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:65536  Metric:1
          RX packets:1283 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1283 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:183079 (183.0 KB)  TX bytes:183079 (183.0 KB)

ppp0      Link encap:Point-to-Point Protocol  
          inet addr:10.13.147.136  P-t-P:10.64.64.64  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:6478 errors:0 dropped:0 overruns:0 frame:0
          TX packets:7867 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3 
          RX bytes:2817719 (2.8 MB)  TX bytes:967126 (967.1 KB)

wlan0     Link encap:Ethernet  HWaddr 08:3e:8e:16:60:2b  
          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:17 

How can I enable my lan now and obtain internet connection? I am using LenovoG470. It apparently got went and since then I can't use wifi so I'm trying use wired cables as of now. Is this already a hardware issue to be fixed by technical means?

Solution

Open a terminal using CtrlAltT.

Take a backup of this file first using (sudo cp /etc/network/interfaces /etc/network/interfaces.old) and then edit it:

sudo nano /etc/network/interfaces

Paste following content in your file Remove everything else

# The loopback network interface

auto lo
iface lo inet loopback

save and exit file then try following commands.

sudo rfkill list all
sudo rfkill unblock all
sudo /etc/init.d/networking restart
sudo ip link set dev eth0 down
sudo stop network-manager
sudo start network-manager