Configuring broker persistence
Session Manager brokers support integration with external databases. The external database allows Session Manager to persist status data and keys so they are available afterwards. In fact the broker data is distributed over the cluster, making it susceptible to data loss if a host needs to reboot or a cluster is terminated. With this feature enabled, you can add and remove broker nodes. Also, you can stop a cluster and restart it, without the need to regenerate keys or lose information about which Amazon DCV Server is open or closed.
The following types of information can be set to persist:
Keys for setting up sessions to establish connection with clients
In-flight sessions data
Amazon DCV server status
Amazon DCV Session Manager supports DynamoDB, MariaDB, and MySQL databases. You must set up and manage one of these databases to use this feature. If your broker machines are hosted on Amazon EC2, we recommend using DynamoDB as the external database, since it does not require any additional setup.
Note
You may incur additional costs when running an external database. To see information on DynamoDB pricing, see
Pricing for Provisioned Capacity
Configure the broker to persist on DynamoDB
Configure the brokers to start storing their data on DynamoDB:
Open
/etc/dcv-session-manager-broker/session-manager-broker.properties
using your preferred text editor and make the following edits:Set
enable-persistence = true
Set
persistence-db = dynamodb
For
dynamodb-region
specify the &aws; Region where you want to store the tables containing the broker data. For the list of supported Regions, see DynamoDB service endpoints. For
dynamodb-table-rcu
specify the amount of Read Capacity Units (RCU) that each table supports. For more information about RCU, see DynamoDB provisioned capacity. For
dynamodb-table-wcu
specify the amount of Write Capacity Units (WCU) that each table supports. For more info on WCU, see DynamoDB provisioned capacity. For dynamodb-table-name-prefix specify the prefix that is added to each DynamoDB table (useful to distinguish multiple broker clusters using the same account). Only alphanumeric characters, dot, dash, and underscore are allowed.
Stop all the brokers in the cluster. For each broker, run the following command:
sudo systemctl stop dcv-session-manager-broker
Ensure all brokers in the cluster are stopped and then restart all of them. Start each broker by running the following command:
sudo systemctl start dcv-session-manager-broker
The broker host must have permission to call the DynamoDB APIs. On Amazon EC2 instances, the
credentials are automatically retrieved using the Amazon EC2 metadata service. If you need to
specify different credentials, you can set them using one of the supported credential
retrieval techniques (such as Java system properties or environment variables). For more
information, see Supplying and Retrieving &aws; Credentials
Configure the broker to persist on MariaDB/MySQL
Note
The /etc/dcv-session-manager-broker/session-manager-broker.properties
file contains sensitive data. By default,
its write access is restricted to root and its read access is restricted to root and to the user running the Broker. By default,
this is the dcvsmbroker
user. The Broker checks at startup that the file has the expected permissions.
Configure the brokers to start persisting their data on MariaDB/MySQL:
Open
/etc/dcv-session-manager-broker/session-manager-broker.properties
with your preferred text editor and make the following edits:Set
enable-persistence = true
Set
persistence-db = mysql
Set
jdbc-connection-url = jdbc:mysql://
<db_endpoint>
:<db_port>
/<db_name>
?createDatabaseIfNotExist=trueIn this configuration, <db_endpoint> is the database endpoint, <db_port> is the database port, and <db_name> is the database name.
For
jdbc-user
specify the name of the user that has access to the database.For
jdbc-password
specify the password of the user that has access to the database.
Stop all the brokers in the cluster. For each broker, run the following command:
sudo systemctl stop dcv-session-manager-broker
Ensure all brokers in the cluster are stopped, and then restart all of them. For each broker, run the following command:
sudo systemctl start dcv-session-manager-broker