"NO NETWORK DETECTED" error after reboot of VMware Aria Operations node

Products

• VCF Operations

Issue/Introduction

• The cluster is a HA enabled cluster
• Steps to reproduce: 
  1. Signed into VMware Aria Operations Admin UI for example https://vcfops-masternode-fqdn/admin/
  2. Selected Replica Node → Click the Take Node Offline/Online button to take the Replica node offline →  Powered off the Replica node from vCenter → Powered on the Replica node from vCenter → Click the Take Node Offline/Online button.   
  3. Selected Primary node  → Click the Take Node Offline/Online button to take the Primary node offline →  Powered off the Primary node from vCenter → Powered on the Primary node from vCenter → Primary node on boot up returns the below error 

     NO NETWORK DETECTED. PLEASE CHECK THE NETWORK CONFIGURATION.
     For more details, log in and examine the following log:
     /opt/vmware/var/log/urops_network_manager.log

  4. /opt/vmware/var/log/vrops_network_manager.log may show error similar to below :

     The given file does not exist, unable to backup: /etc/systemd/network/10-eth0.network.d/ipv4.conf

•  /etc/systemd/network/10-eth0.network.d/ipv4.conf exists with valid entries 
• All vApp properties are correct for the node in vCenter.  You can use the following as a guide Configure vApp Properties
• /etc/hosts, /etc/systemd/network/10-eth0.network and /opt/vmware/etc/ovfEnv.xml or /opt/vmware/etc/vami/ovfEnv.xml depending on your environment have correct entries

Environment

VMware Aria Operations 8.18.x

Resolution

1. Sign into VMware Aria Operations Admin UI for example https://vcfops-masternode-fqdn/admin/ 
2. Take the Replica and any Data nodes you have in the cluster offline by selecting the node → Click the Take Node Offline/Online button.  If you are unable to take the node offline using the UI method you can open a ssh session as root to the node and run the below commands:

   Stop the services: service vmware-vcops stop 
   Bring the node offline: sed -i -e 's/sliceonline = true/sliceonline = false/' /usr/lib/vmware-vcopssuite/utilities/sliceConfiguration/data/roleState.properties

3. Take snapshot of the nodes in the cluster using the following KB as a guide Snapshot Creation in VMware Aria Operations
4. Reboot all nodes in the cluster in the order listed in the KB Shutdown and Startup sequence for Aria Operations cluster
5. Bring the cluster back online through the VMware Aria Operations Admin UI

Additional Information

Error 'NO NETWORK DETECTED' on newly deployed VMware Aria Operations

Aria Operations UI becomes inaccessible during upgrade with the appliance reporting No network detected error

NO NETWORK DETECTED during the rebooting process when upgrading Aria Operations