Connecting clusters
Enterprise Edition
Tarantool Cluster Manager is a part of the Enterprise Edition.
Tarantool Cluster Manager works with clusters that:
- run on Tarantool EE 3.0 or later
- use centralized configuration stored in etcd or another Tarantool cluster.
A single TCM installation can have multiple connected clusters. A connection to TCM doesn’t affect the cluster’s functioning. You can connect clusters to TCM and disconnect them on the fly.
There are two ways to add a cluster to TCM:
- Connect an existing cluster.
- Add a new cluster and write its configuration from scratch in the TCM web UI.
In both cases, you need to deploy Tarantool and start the cluster instances using the tt CLI utility or another suitable way.
When connecting a cluster to TCM, you need to provide two sets of connection parameters: for the cluster instances and for the centralized configuration storage.
The cluster configuration can be stored in either an etcd cluster or a separate Tarantool-based storage. In both cases, the following connection parameters are required:
- A key prefix used to identify the cluster in the configuration storage. A prefix must be unique for each cluster in storage.
- URIs of all instances of the configuration storage.
- The credentials for accessing the configuration storage: an etcd user or a Tarantool user.
Additionally, if SSL or TLS encryption is enabled for the configuration storage, provide the corresponding encryption configuration: keys, certificates, and other parameters. For the complete list of parameters, consult the etcd documentation or Tarantool Securing connections with SSL.
For interaction with the cluster instances, TCM needs the following access parameters:
- A Tarantool user that exists in the cluster and their password. TCM connects to the cluster on behalf of this user.
- An SSL configuration if the traffic encryption is enabled on the cluster.
Administrators can add new clusters, edit, and remove existing ones from TCM.
Connected clusters are listed on the Clusters page.
If you already have a cluster and want to connect it to TCM, follow these steps:
- Go to Clusters and click Add.
- Fill in the general cluster information:
- Specify an arbitrary name.
- Optionally, provide a description and select a color to mark this cluster in TCM.
- Optionally, enter the URLs of additional services for the cluster. For example, a Grafana dashboard that monitors the cluster metrics, or a syslog server for viewing the cluster logs. TCM provides quick access to these URLs on the cluster Stateboard page.
- Provide the details of the cluster configuration storage:
- Storage type: etcd or tarantool.
- The Prefix specified in the cluster configuration.
- The URIs of the configuration storage instances.
- The credentials for accessing the configuration storage.
- The SSL/TLS parameters if the connection encryption is enabled on the storage.
- Provide the credentials for accessing the cluster: a Tarantool user’s name, their password, and SSL parameters in case traffic encryption is enabled on the cluster.
If you don’t have a cluster yet, you can add one in TCM and write its configuration from scratch using the built-in configuration editor.
Important
When adding a new cluster, you need to have a storage for its configuration up and running so that TCM can connect to it. Cluster instances can be deployed later.
To add a new cluster:
- Go to Clusters and click Add.
- Fill in the general cluster information:
- Specify an arbitrary name.
- Optionally, provide a description and select a color to mark this cluster in TCM.
- Optionally, enter the URLs of additional services for the cluster. For example, a Grafana dashboard that monitors the cluster metrics, or a syslog server for viewing the cluster logs. TCM provides quick access to these URLs on the cluster Stateboard page.
- Select the type of the cluster configuration storage: etcd or tarantool.
- Define a unique Prefix for identifying this cluster in the configuration storage.
- Provide the connection details for the cluster configuration storage:
- The URIs of configuration storage instances.
- The credentials for accessing the configuration storage.
- The SSL/TLS parameters if the connection encryption is enabled on the storage.
- Provide the cluster credentials: a username, a password, and SSL parameters in case traffic encryption is enabled on the cluster.
Once you add the cluster:
- Set up the cluster configuration using the TCM configuration editor.
- Deploy Tarantool on the cluster nodes using the tt CLI utility or other suitable tools.
- Start the cluster using the tt CLI utility or other suitable tools.
To edit a connected cluster, go to Clusters and click Edit in the Actions menu of the corresponding table row.
To disconnect a cluster from TCM, go to Clusters and click Disconnect in the Actions menu of the corresponding table row.
Note
Disconnecting a cluster does not affect its functioning. The only thing that changes is that it’s no longer shown in TCM. You can connect this cluster again at any time.