GridGain Developers Hub

Frequently Asked Questions

This section contains answers to common questions and recommendations for common issues.

Issues With Clusters

My cluster failed to start

If your cluster failed to start during provisioning, try to provision one more cluster with the same settings. Sometimes cloud-related issues happen during provisioning, and the cluster fails to start and connect to GridGain Nebula. These issues are investigated by the support team.

You will not be billed for the cluster that did not start.

My cluster is disconnected

A disconnected cluster is still running, just not connected to GridGain Nebula. Click the ⋮ and select Connect to reconnect to the cluster.

Connection Issues

I cannot connect to a newly created cluster

Sometimes DNS propagation may take time and, until it is complete, your cluster would not be available. If you see unkown host error when you try to connect, try running the nslookup your_cluster_address command. If the command fails to find the cluster, wait for a bit and try again.

I am getting SSL error during connection

Most likely you are using an older client version. For example, here is an error you can get in Java:

class org.apache.ignite.IgniteException: Failed to initialize SSL context (parameter cannot be null): keyStoreFilePath
	at org.apache.ignite.ssl.SslContextFactory.create(
	at org.apache.ignite.ssl.SslContextFactory.create(
	at org.apache.ignite.spi.communication.tcp.internal.GridNioServerWrapper.resetNioServer(

You can see the required client version in connection templates.

My application cannot connect to the cluster

Most likely, you are using an incorrect client version. Please check that the client version is the same as the GridGain version run by Nebula cluster, and, if that does not help, contact us at

How do I contact support?

To contact support from the UI, use the Contact Us button in top-right of the screen. You can also send an e-mail to Our team is constantly monitoring feedback.А