Symptoms:

• A node may be duplicated on the Administration > Cluster Management page.
• A node is powered off and deleted without removing it from the VMware vRealize Operations cluster. The node is listed as inaccessible.
• Attempts to gracefully remove the node from either of the scenarios does not succeed.
• The main vRealize Operations UI may not be accessible.

VMware vRealize Operations Manager 6.6.x
VMware vRealize Operations Manager 7.5.x
VMware vRealize Operations Manager 7.0.x
VMware vRealize Operations 8.1.x
VMware vRealize Operations 8.0.x
VMware vRealize Operations Manager 6.7.x
VMware vRealize Operations 8.x

To resolve this issue, use one of these options:

• Remove the Data or Remote Collector node by running this command as root from any of the nodes in the cluster:
  
  curl -ik -u 'admin:password' -X DELETE https://primary_node_IP/casa/deployment/slice/node_to_remove_IP
  
  Where:
  • password is the admin user password
  • primary_node_IP is the IP of the Primary node
  • node_to_remove_IP is the IP of the node that you want to remove from the cluster
     
• Remove the Primary or a Replica node by running this command as root from any of the nodes in the cluster:

• HA must be enabled for this call to succeed.
• Large clusters might take additional time to repopulate the data.

• password is the admin user password
• primary_node_IP is the IP of the Primary node
• node_to_remove_IP is the IP of the node that you want to remove from the cluster
• replacement_node_IP is the IP of the node that replaces the Primary or Replica node that you are removing

It may be necessary to reboot all nodes in the vRealize Operations cluster after making the changes in the configuration files noted in the preceding section.从 VMware vRealize Operations 6.x 群集中手动移除节点
[Internal] Removing a Node from Cassandra in vRealize Operations 6.x

Impact/Risks:
The below steps will only be successful if the cluster is in a clean Online or Offline state.
Do not attempt the below steps if the cluster is in a failed state, or in the middle of expanding or shrinking the cluster; instead, contact VMware Support for assistance.

Ensure you have a valid snapshot or backup of the vRealize Operations cluster before proceeding.
See How to take a Snapshot of vRealize Operations for more information.