"Error: connection activation failed: Device not managed by NetworkManager or unavailable" after moving machine

[Rick Stevens]

On 09/03/2013 03:01 PM, Aaron Gray issued this missive:
> Hi,
>
> "Error: connection activation failed: Device not managed by
> NetworkManager or unavailable"
>
> I am getting the above error and have tried all my normal mods to try
> and get a connection.
>
> I did move the SATA drive from one machine to another and back,
> changing the MAC address and putting it back in the process.
>
> I have tried adding 'NM_CONTROLLED="yes"' to
> /etc/sysconfig/network-scripts/ifcfg-em1
>
> but still am not able to get it to work.
>
> As I cannot connect to the internet on this device I cannot do any yum
> reinstalls.

Are you certain the device is still called "em1"? As root, try "ifconfig 
-a".

Several revisions ago many network devices were renamed based on the
bus they were on and where they appeared on the bus. For example, my
old "eth0" got renamed "p4p1". My "wlan0" card was also a candidate,
so I added a rule to "/etc/udev/rules.d/70-persistent-net.rules" to
keep the old "wlan0" name. The rule looks like:

# PCI device 0x8086:0x008a (iwlagn)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", 
ATTR{address}=="bc:77:37:51:11:5c", ATTR{dev_id}=="0x0", 
ATTR{type}=="1", KERNEL=="wlan*", NAME="wlan0"

You could do something similar. Note that the "bc:77:37:51:11:5c"
is the MAC address of my wireless card. You can extract that from the
"ifconfig -a" data...it's the thing listed after "ether" in the listing.
----------------------------------------------------------------------
- Rick Stevens, Systems Engineer, AllDigital    ricks at alldigital.com -
- AIM/Skype: therps2        ICQ: 22643734            Yahoo: origrps2 -
-                                                                    -
-   I haven't lost my mind.  It's backed up on tape somewhere, but   -
-                       probably not recoverable.                    -
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