ArangoDB v3.12 is under development and not released yet.
This documentation is not final and potentially incomplete.
Cluster Troubleshooting
- Cluster front end is unresponsive
    
- Check if the Coordinator(s) in question are started up.
 - Check if the Agency is up and a leader has been elected. If not ensure that all or a majority of Agents are up and running.
 - Check if all processes have been started up with the same
JWT_SECRET. If not ensure that theJWT_SECRETused across the cluster nodes is identical for every process. - Check if all cluster nodes have been started with SSL either dis- or enabled. If not decide what mode of operation you would like to run your cluster in, and consistently stick with for all Agents, Coordinators and DB-Servers.
 - Check if network communication between the cluster nodes is such that all processes can directly access their peers. Do not operate proxies between the cluster nodes.
 
 - Cluster front end announces errors on any number of nodes
    
- This is an indication that the Agency is running but either Coordinators or DB-Servers are disconnected or shut down. Establish network connection to or start the according nodes.
 - Make sure that the nodes in question share the same 
JWT_SECRETand SSL operation mode with the functioning nodes. 
 
Dig deeper into cluster troubleshooting by going through the ArangoDB Cluster Administration Course.