eth0 connection failed: Device not managed by NetworkManager

[megaloman]

Yesterday I did an upgrade and today my box is unable to connect to the internet.

I have tried another cable, it didn't help.

Basically NetworkManager does not connect eth0 to the network, if I try to run ifup from the command line I get:

Error: Connection activation failed: Device not managed by NetworkManager

I can see in network configuration settings, that the device has been correctly detected and eth0 interface is correctly activated, yet when I try to uncheck the box “manage by NetworkManager” and start it manually, it tells me that the cable is disconnected... I've tried two different cables, different ports on my router - no help :-(

any idea?

thanks in advance!

[scott32746]

Hello,

I like to use network for cable,, You may want to try it.
On a side note, my eth0 is an onboard eth stop working after update, had to add a NIC.
I have read other post of the same.

[megaloman]

the issue is - yesterday it worked fine, I just switched off my machine and today it didn't work.

I've tried both cables I used for testing, with my laptop and they work flawlessly, yet my machine tells me:

r8169: eth0: link down
ADDRCONF(NETDEV_UP): eth0: link is not ready

this is an onboard nic, yet it gets detected by Fedora 13 but does not work. same cable works fine with the other laptop :-/

[marko]

The "network" service would likely be more robust for handling your hard wired eth0 port than the NetworkManager, try running as root:

system-config-network

select the eth0 device and hit the Edit button
and uncheck the "Controlled by network manager" check box and check the box for Activating the port when the computer starts up. Save and quit in there.

Now run system-config-services and stop/disable NetworkManager and start/enabled network service.

[ktmariappan]

Please do below steps

Change yes to no "NM_CONTROLLED" on /etc/sysconfig/network-scripts/ifcfg-eth0

Example:
.
.
NM_CONTROLLED=yes =====> NM_CONTROLLED=no

If your os are redhat 6/fedora14&above/centos 6

[dsmithhfx]

I've been having consistent problems with Network Manager after all recent updates (after kernel 3.30-4). It doesn't seem to matter what the updates are, whether they include networking components and/or kernel upgrades.

Each time the same thing happens: after applying the update, NM fails to establish a wired connection on reboot.

Fortunately for me, so far, there is a temporary fix: stop networking (from the top menu bar), open the NM gui applet, delete and recreate the eth device, and restart networking. After doing this, NM successfully establishes a connection immediately and on subsequent reboots, until the next update is applied (again -- so far). YMMV.

The first time it happened I posted a query here (much like yours), and went on to try a bunch of stuff including rolling back iproute to a prior version, and disabling ipv6.

In hindsight, since the problem keeps coming back, I doubt these modifications made any real difference to the underlying issue(s).

[marko]

Note these last few posts (5 and 6) were tacked onto a dead thread from Aug 2010, so some of the information in this is stale. Please create a new thread for this so your posts can be properly addressed in the modern Fedora 16 context.

[dsmithhfx]

So... Network Manager: Still Broken After All These Years?

[gene0]

Originally Posted by ktmariappan

Please do below steps

Change yes to no "NM_CONTROLLED" on /etc/sysconfig/network-scripts/ifcfg-eth0

Example:
.
.
NM_CONTROLLED=yes =====> NM_CONTROLLED=no

If your os are redhat 6/fedora14&above/centos 6

OK I do not have a /etc/sysconfig/network-scripts/ifcfg-eth0 file. FC16 X64 does that make a difference?
I can make everything work on wireless card but lan is killing me.

[marko]

Originally Posted by gene0

OK I do not have a /etc/sysconfig/network-scripts/ifcfg-eth0 file. FC16 X64 does that make a difference?
I can make everything work on wireless card but lan is killing me.

the ifcfg file won't necessarily be called ifcfg-eth0, it might be ifcfg-em1 or ifcfg-pXpY with any number of different permutations for the two numbers X and Y. The prefix name depends on whether Fedora finds the port on the motherboard ("em" as in embedded for the prefix) or pXpY where the X and Y are numbers representing the id's related to the bus.

It might be worthwhile to load system-config-network and try to set it up in that tool

For some reason it's not a default package so you might need to run:

yum install system-config-network

[gene0]

Thanks Marko, I have installed system-config-network and will try it to see if it works.

[gene0]

Did not work for me. Thanks!