Virtualbox Bridged network ethernet cable disconnecting

Question

I’m trying to connect to a ethernet device (like a scanner/printer) to a guest Ubuntu 12.04 running on Virtualbox 4.3.12. The scanner is connected to the Mac Pro directly over ethernet cable. Problems faced: 1) The ethernet connection gets disconnected and the ip needs to be set again to reconnect. 2) How to permanently set a static ip to the bridge adaptor connection?

System: Host: Mac Pro running OS X 10.9.3 Guest: Ubuntu 12.04 32-bit Virtualbox settings: Bridged adaptor Device connected on ethernet (scanner) demands: the network settings of the Ethernet adapter set from automatic IP address to manual IP address selection with: IP address: 192.168.1.X (here X can be 0 to 100) Gateway: 255.255.255.0

In terminal (TERMINAL_STATE 0):

viki@c3po:~$ ifconfig
eth0      Link encap:Ethernet  HWaddr 08:00:27:b3:ed:c7  
          inet6 addr: fe80::a00:27ff:feb3:edc7/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:4195220 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1800 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:651884753 (651.8 MB)  TX bytes:381818 (381.8 KB)

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NOTE: There is no IP address in the line after eth0 . Why?

Later in terminal (TERMINAL_STATE 1):

viki@c3po:~$ sudo ifconfig eth0 192.168.1.1
viki@c3po:~$ ifconfig 
eth0      Link encap:Ethernet  HWaddr 08:00:27:b3:ed:c7  
          inet addr:192.168.1.1  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::a00:27ff:feb3:edc7/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:2540914 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1454 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:2995685395 (2.9 GB)  TX bytes:308913 (308.9 KB)

---

At this point, the ubuntu wireless network icon is passive (looks like a sector of a circle): https://drive.google.com/file/d/0B2hiq6P5ceD-WTJhMDJ1MlNwWlU/edit?usp=sharing

Within a minute or two, the wireless network icon starts blinking (the sector has waves in it):

Finally, in a few seconds, I get a warning Wired Network Disconnected - You are now offline : https://drive.google.com/file/d/0B2hiq6P5ceD-bFp2NjhxaE5EQTA/edit?usp=sharing

Now if I do a ifconfig, I get same response as TERMINAL_STATE 0 mentioned earlier.

Later, if I set the ip again using sudo ifconfig eth0 192.168.1.1 then I get reconnected.

Solution

grep managed /etc/NetworkManager/NetworkManager.conf to see if network manager trying to DHCP an address and fails. On top of the whole wireless confusion sudo ifconfig eth0 192.168.1.1 only sets ip temporary (until you reboot or restart the service) you need to set static IPs in /etc/network/interfaces like this:

auto lo
iface lo inet loopback

auto eth0
iface eth1 inet static
address 192.168.1.1
netmask 255.255.255.0

Comments

[meccooll]

Ummm what does wireless network has to do with your eth0 connection? eth0 is your ethernet cable connection not wireless

[tripleee]

I'm seeing some serious network flap on Virtualbox on a Windows 7 host. This seems to be a recent regression. See virtualbox.org/ticket/13839