Unable to get ifup & ifdown to bring up eth0 | Ubuntu 14.04

Question

I'm trying to set up a static IP on a dual boot laptop ( Win10 and Ubuntu Studio 14.04). These are the settings:

sudo nano /etc/network/interfaces:

# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet static
address         192.168.1.101
    netmask         255.255.255.0
    network         192.168.1.0
    broadcast       192.168.1.255
    gateway         192.168.1.1
    dns-nameservers 192.168.1.1 8.8.8.8
    dns-domain example.com
    dns-search example.com

sudo nano /etc/NetworkManager/NetworkManager.conf:

/etc/NetworkManager/NetworkManager.conf
[main]
plugins=ifupdown,keyfile,ofono
#dns=dnsmasq
no-auto-default=54:04:A6:25:64:2E,
[ifupdown]
managed=true

(there is a line space above and below "no-auto--")

The ifconfig returns the below:

eth0      Link encap:Ethernet  HWaddr 54:04:a6:25:64:2e  
      inet addr:192.168.1.101  Bcast:192.168.1.255  Mask:255.255.255.0
      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:312 errors:0 dropped:0 overruns:0 frame:0
      TX packets:312 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1 
      RX bytes:29521 (29.5 KB)  TX bytes:29521 (29.5 KB)

      wlan0     Link encap:Ethernet  HWaddr 78:92:9c:45:05:ae  
      inet addr:192.168.43.110  Bcast:192.168.43.255  Mask:255.255.255.0
      inet6 addr: fe80::7a92:9cff:fe45:5ae/64 Scope:Link
      UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
      RX packets:2631 errors:0 dropped:0 overruns:0 frame:0
      TX packets:2507 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1000 
      RX bytes:1816247 (1.8 MB)  TX bytes:375757 (375.7 KB)

sudo ifdown eth0 returns

 `RTNETLINK answers: No such process

Any advice from pros what I should try to get it right? The targetted configuration is : eth0 up / internet connectivity while eth0 is up. I can post router and gui network manager settings.

sudo ifup eth0 elicits this response:

 `RTNETLINK answers: File exists
  Failed to bring up eth0.`

Solution

Please try '=false' and restart Network Manager:

sudo service network-manager restart

Your interfaces file looks a bit busy; I'd amend it to:

# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address 192.168.1.101
netmask 255.255.255.0
gateway 192.168.1.1
dns-nameservers 192.168.1.1 8.8.8.8
dns-domain example.com
dns-search example.com

Then try again:

sudo ifdown eth0 && sudo ifup -v eth0

Did you connect?

ping -c3 www.ubuntu.com

Comments

[Autoresponder]

Tried with both 'true' and 'false' - there's no connectivity - i need eth0 up and connecting to the net.

[Autoresponder]

I de-indented the interfaces file, thanks. And No. The console had this to say : when I ran the second command :** ifdown: interface eth0 not configured Configuring interface eth0=eth0 (inet) run-parts --verbose /etc/network/if-pre-up.d run-parts: executing /etc/network/if-pre-up.d/wireless-tools run-parts: executing /etc/network/if-pre-up.d/wpasupplicant ip addr add 192.168.1.101/255.255.255.0 broadcast 192.168.1.255 dev eth0 label eth0 ip link set dev eth0 up ip route add default via 192.168.1.1 dev eth0 RTNETLINK answers: File exists Failed to bring up eth0.**

[chili555]

Are there any clues in the log? cat /var/log/syslog | grep eth0 ? As the result may be lengthy, paste the result here and give us the link: paste.ubuntu.com What is the ethernet driver? Find it from sudo lshw -C network driver=??

[Autoresponder]

Sorry I took awhile- had to boot back into windows after commands on the other OS. The 'networks' graphical symbol has completely vanished from the top menu. The pastebin is here: paste.ubuntu.com/23673821

[chili555]

Ahhh! The infamous r8169! Please try: sudo ethtool -s eth0 autoneg off speed 100 and then: sudo ifdown eth0 && sudo ifup -v eth0 Any change?

[Autoresponder]

thanks for pointing out the r8169 driver part. (It wasn't easy with zilch connectivity). I downloaded stuff via windows and rebooted into ubuntu to config. The new driver shows up, but still no internet. Pastebin here, appreciate any further advice on whatever cranking I need to do to get eth0 up and running with access to internet.paste.ubuntu.com/23677673 have a great holiday season!

[chili555]

Your eth0 appears to be connected; it has the requested IP address. May I assume that you've carefully checked the numbers? 192.168.1.1; not x.0.1, etc.? Can you ping the gateway? ping -c3 192.168.1.1 If so, how about: ping -c3 8.8.8.8 ? With the newer driver, may we see: sudo ifdown eth0 && sudo ifup -v eth0 and: sudo ethtool eth0 paste.ubuntu.com please.

[Autoresponder]

paste.ubuntu.com/23677963 I'm risking moderator attention by ignoring the "avoid extended discussions.." warning - it isn't feasible to move to chat because I'd have to reboot between OS's to find the data you want to de-geek while you're waiting! Thanks for taking the trouble! Did I mess up in router settings- I've port-forwarded (http to port 80) to the eth0 IP?

[chili555]

See in the paste it says "Link detected: no"? I still think you'll have to: sudo ethtool -s eth0 autoneg off speed 100 to see a link. Check: sudo ethtool eth0 We can automate the autoneg and speed if it works as I expect.