NetworkManager restart fails with: device state change: prepare -> failed (reason 'dependency-failed')

Issue

• NetworkManager comes up on boot, but a systemctl restart NetworkManager.service fails to activate bond slaves. The following messages are logged:

NetworkManager[141659]: <info>  (ens4f1): device state change: disconnected -> prepare (reason 'none') [30 40 0]
NetworkManager[141659]: <info>  (ens5f1): device state change: disconnected -> prepare (reason 'none') [30 40 0]
NetworkManager[141659]: <info>  (ens7f1): device state change: disconnected -> prepare (reason 'none') [30 40 0]
NetworkManager[141659]: <info>  (ens8f1): device state change: prepare -> failed (reason 'dependency-failed') [40 120 50]
NetworkManager[141659]: <info>  Disabling autoconnect for connection 'ens8f1'.
NetworkManager[141659]: <warn>  (ens8f1): Activation: failed for connection 'ens8f1'
NetworkManager[141659]: <info>  (ens4f1): device state change: prepare -> failed (reason 'dependency-failed') [40 120 50]
NetworkManager[141659]: <info>  Disabling autoconnect for connection 'ens4f1'.
NetworkManager[141659]: <warn>  (ens4f1): Activation: failed for connection 'ens4f1'
NetworkManager[141659]: <info>  (ens5f1): device state change: prepare -> failed (reason 'dependency-failed') [40 120 50]
NetworkManager[141659]: <info>  Disabling autoconnect for connection 'ens5f1'.
NetworkManager[141659]: <warn>  (ens5f1): Activation: failed for connection 'ens5f1'
NetworkManager[141659]: <info>  (ens7f1): device state change: prepare -> failed (reason 'dependency-failed') [40 120 50]
NetworkManager[141659]: <info>  NetworkManager state is now DISCONNECTED
NetworkManager[141659]: <info>  Disabling autoconnect for connection 'ens7f1'.
NetworkManager[141659]: <warn>  (ens7f1): Activation: failed for connection 'ens7f1