Resizing database servers

Database servers cannot be resized in-place on MedStack Control, although it is a feature we intend on supporting in the near future. In order to switch between database server sizes, you'll need to:

1. Provision the target database server.
2. Perform a migration from the source database to the target.
3. Destroy the source database server.

Migrating a database

Prerequisite: Both the source and target database instances exist.

In reference to step 2 above, migrating a database is commonly done through one of two (2) methods.

1. Via MedStack Control
2. Via Endpoint with Allowed IP

Via MedStack Control – Recommended

Using the container shell feature, you can use an existing service with a CLI utility deployed in a cluster to send commands to the database server.

Steps:

Note: You can grab the SSL Certificate for the connection string here for PostgreSQL db or MySQL db. 

1. Shell into the container where database client CLI is installed. Ideally your application container would have a database client installed. 
2. Grab the connection strings for the Old database that you would like to migrate the data from. 
3. Use a mysqldump or pg_dump CLI tool to create a backup of the database.
   

   mysqldump -h [host] -u [user name] –p [password] [options] [database_name] [tablename] > [dumpfilename.sql]

   pg_dump -h [host] -U [username] -W -F c [database_name] > backup.tar

4. Grab the connection strings for the New database server.
5. Use mysql or pg_restore CLI tool to restore the backup on to the new Database
6. Connect to the new database from the container using the CLI. 

   psql -d "host=[host] port=5432 dbname=[database_name] user=[username]"

7. Verify the data has been restored successfully. 
8. Delete the backup from container. 
9. Monitor the new Database server for any missing data or for stability. 
10. Once you are comfortable with the new database server, delete the Old database server from MedStack. 

Via Endpoint with Allowed IP

An endpoint in this example could represent a local dev machine, workstation, static server, etc. which has an IP address that's allowed to connect to the database server in the cluster.

Steps:

Note: You can grab the SSL Certificate for the connection string here for PostgreSQL db or MySQL db. 

1. Add your public IP address to the Allowed IP list on both Old and New Database server.
2. Grab the connection strings for the Old database that you would like to migrate the data from. 
3. Connect to the Old database from your local machine. (screenshot below shows a connection to a PostgreSQL database server running on MedStack using PgAdmin tool, however same can be done with MySQL database using MySQL Workbench)
4. Backup the database to your local machine.
5. Grab the connection strings for the New database server.
6. Connect to the New database server from you local machine.
7. Restore the database backup to the new Database server.
8. Verify the data has been restored successfully. 
9. Delete the backup from your local machine. 
10. Monitor the new Database server for any missing data or for stability. 
11. Once you are comfortable with the new database server, delete the Old database server from MedStack.