Proxmox on OVH

adding another update
although they have not replied yet...

Ordered another Advanced 1 server and everything is working as expected.
Seems there is an issue with the Advanced 3 server ( either mine or the network infra in general )

i will add the final update once OVH support find a solution for the Advanced 3, incase anyone in the feature stumbled across this thread.
 
Okay seems the issue was indeed with the Actual Server being defected, after OVH changed the motherboard everything is working again.
It worked when aggregation ( OLA ) is activated because the public NIC was being used on the vRack, which led to the conclusion that the private NIC is defected.

@_gabriel , yes this is valid however it wasn't the case at my end, since the Advanced 3 server had Intel NICs
theres is also an issue i saw while searching related to VLANs > 126 , but that wasn't the case as well.

All in all the issue was at OVH side, and when they replaced the motherboard and booted back the server Proxmox API's were dead, and the cluster hanged, ( VM's working though ), i haven't troubleshooted further but as soon as i powered off the server that had issues everything came back online.

Thanks everyone for your comments, and if anyone stumbled across the same issue at OVH do not waste your time/money troubleshooting ( DAYS ), it is most likely to be a NIC defected.