Hi,

The main issue here is the Logical that cannot be attached to the 3rd node (please check attached AttachErr.png file), while it has attached to the other two nodes.

The Logical Network configurations are the same in all 3 networks., please check the logical configurations in attached scrnshot2.png file

Here are the logs grepped from engine.log file:

[root@engine ~]# tail -f  /var/log/ovirt-engine/engine.log | egrep "${OUT_OF_SYNC_VALUES} | goku.sanren.ac.za"
2018-10-11 13:52:20,779+02 INFO  [org.ovirt.engine.core.bll.storage.ovfstore.ProcessOvfUpdateForStoragePoolCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-13) [555cc9ce] Before acquiring and wait lock 'EngineLock:{exclusiveLocks='[722583f2-b11a-11e8-9a47-00163e5858df=OVF_UPDATE]', sharedLocks=''}'
2018-10-11 13:52:20,779+02 INFO  [org.ovirt.engine.core.bll.storage.ovfstore.ProcessOvfUpdateForStoragePoolCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-13) [555cc9ce] Lock-wait acquired to object 'EngineLock:{exclusiveLocks='[722583f2-b11a-11e8-9a47-00163e5858df=OVF_UPDATE]', sharedLocks=''}'
2018-10-11 13:52:20,780+02 INFO  [org.ovirt.engine.core.bll.storage.ovfstore.ProcessOvfUpdateForStoragePoolCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-13) [555cc9ce] Running command: ProcessOvfUpdateForStoragePoolCommand internal: true. Entities affected :  ID: 722583f2-b11a-11e8-9a47-00163e5858df Type: StoragePool
2018-10-11 13:52:20,784+02 INFO  [org.ovirt.engine.core.bll.storage.ovfstore.ProcessOvfUpdateForStoragePoolCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-13) [555cc9ce] Attemptin  to update VM OVFs in Data Center 'Default'
2018-10-11 13:52:20,789+02 INFO  [org.ovirt.engine.core.bll.storage.ovfstore.ProcessOvfUpdateForStoragePoolCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-13) [555cc9ce] Successfully updated VM OVFs in Data Center 'Default'
2018-10-11 13:52:20,789+02 INFO  [org.ovirt.engine.core.bll.storage.ovfstore.ProcessOvfUpdateForStoragePoolCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-13) [555cc9ce] Attemptin  to update template OVFs in Data Center 'Default'
2018-10-11 13:52:20,790+02 INFO  [org.ovirt.engine.core.bll.storage.ovfstore.ProcessOvfUpdateForStoragePoolCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-13) [555cc9ce] Successfully updated templates OVFs in Data Center 'Default'
2018-10-11 13:52:20,790+02 INFO  [org.ovirt.engine.core.bll.storage.ovfstore.ProcessOvfUpdateForStoragePoolCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-13) [555cc9ce] Attemptin  to remove unneeded template/vm OVFs in Data Center 'Default'
2018-10-11 13:52:20,790+02 INFO  [org.ovirt.engine.core.bll.storage.ovfstore.ProcessOvfUpdateForStoragePoolCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-13) [555cc9ce] Successfully removed unneeded template/vm OVFs in Data Center 'Default'
2018-10-11 13:52:20,791+02 INFO  [org.ovirt.engine.core.bll.storage.ovfstore.ProcessOvfUpdateForStoragePoolCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-13) [555cc9ce] Lock free  to object 'EngineLock:{exclusiveLocks='[722583f2-b11a-11e8-9a47-00163e5858df=OVF_UPDATE]', sharedLocks=''}'
2018-10-11 13:55:38,215+02 INFO  [org.ovirt.engine.core.bll.provider.network.SyncNetworkProviderCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-65) [550b0278] Lock Acquired to object 'EngineLock:{exclusiveLocks='[1a7e6539-4a99-4051-9998-803883d118f2=PROVIDER]', sharedLocks=''}'
2018-10-11 13:55:38,226+02 INFO  [org.ovirt.engine.core.bll.provider.network.SyncNetworkProviderCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-65) [550b0278] Running command: SyncNetworkProviderCommand internal: true.
2018-10-11 13:55:38,327+02 INFO  [org.ovirt.engine.core.sso.utils.AuthenticationUtils] (default task-342) [] User admin@internal successfully logged in with scopes: ovirt-app-api ovirt-ext=token-info:authz-search ovirt-ext=token-info:public-authz-search ovirt-ext=token-info:validate ovirt-ext=token:password-access
2018-10-11 13:55:38,483+02 INFO  [org.ovirt.engine.core.bll.provider.network.SyncNetworkProviderCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-65) [550b0278] Lock freed to object 'EngineLock:{exclusiveLocks='[1a7e6539-4a99-4051-9998-803883d118f2=PROVIDER]', sharedLocks=''}'

On Tue, Oct 9, 2018 at 5:01 PM Dominik Holler <dholler@redhat.com> wrote:
On Tue, 9 Oct 2018 13:24:51 +0200
Sakhi Hadebe <sakhi@sanren.ac.za> wrote:

> Hi,
>
> I have a 3-node oVirt cluster. I have configured 2 logical networks:
> ovirtmgmt and public. Public logical network is attached in only 2 nodes
> and failing to attach on the 3rd node with the below error
> Invalid operation, out-of-sync network 'public' can only be detached.
>
> Please  have been stuck on this for almost the whole day now. How do I fix
> this error?
>

The error message in the UI might be include the wrong network name.
I guess the network ovirtmgmt is out-of-sync on the 3rd node.
Why the network is out of sync, is shown as a tooltip if you hover the
mouse pointer over ovirtmgmt in
"Compute > Hosts > 3rd host > Network Interfaces > Setup Host Networks"
If the shown information does not help you, please share a screenshot
of this dialog.

If there is a line like:
The following Network definitions on the Network Interface are different than those on the Logical Network. Please synchronize the Network Interface before editing network ${NETWORK_NOT_IN_SYNC}. The non-synchronized values are\: ${OUT_OF_SYNC_VALUES}.
in engine.log, please share this line, too.


--
Regards,
Sakhi Hadebe
Engineer: South African National Research Network (SANReN)Competency Area, Meraka, CSIR
 
Tel:   +27 12 841 2308
Fax:   +27 12 841 4223
Cell:  +27 71 331 9622
Email: sakhi@sanren.ac.za