Created attachment 1144094 [details]
engine log

Description of problem:
Internal Engine Error when removing an unmanaged network from host NIC in the next scenario:

1) Label NIC with 'lb1' 
2) Network 'n1' attached to this NIC without label
3) Remove network from DC
4) Network 'n1' became 'unamnaged' network
5) No network can be attached to this NIC until removing 'n1' unmanaged network - BZ  1167698
6) Create new vlan network 'n2' with label 'lb1'
7) Create new vlan network 'n3' with label 'lb1' 
8) Create new vlan network 'n4' with label 'lb1' 
9) This networks should be attached to the NIC, but can't because of the unmanaged network, that we should first need to remove. BZ  1167698
10) Remove unmanaged network 'n1' from host via setup networks

Result: 
Internal engine error --> 

Exception thrown in the engine log:

 2016-04-06 08:26:09,161 ERROR [org.ovirt.engine.core.bll.network.host.HostSetupNetworksCommand] (default task-3) [23ce087e] Command 'org.ovirt.engine.core.bll.network.host.HostSetupNetworksCommand' failed: Callabl
eStatementCallback; SQL [{call insertnetworkattachment(?, ?, ?, ?, ?, ?, ?, ?)}]; ERROR: duplicate key value violates unique constraint "network_attachments_network_id_nic_id_key"
  Detail: Key (network_id, nic_id)=(b108800f-a8c2-488b-90ca-0325065ac305, c01e8c79-cc4d-4ebd-b78e-2e062fdd7727) already exists.
  Where: SQL statement "INSERT INTO network_attachments (

On host, the changes took place. The unmanaged network 'n1' was removed from the host, and all other networks that should have been attached to the NIC via the label now attached as they should. 


Version-Release number of selected component (if applicable):
4.0.0-0.0.master.20160404161620.git4ffd5a4.el7.centos.noarch

How reproducible:
100 

Steps to Reproduce:
See description above ^^ 

Actual results:
Internal engine error

Expected results:
Removing of the unamanged should succeed without any engine errors and exceptions. All the other networks that should have been attached to the host NIC via the label attached to the NIC after removing the unmanaged network from the host. 

Additional info:
Discovered during the testing of BZ - 1167698