67 lines
2.1 KiB
Markdown
67 lines
2.1 KiB
Markdown
# DB Failover Testing Utilities
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A set of scripts for testing DB failover scenarios.
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The scripts expect to be run with relative execution prefix `./` from within the `db-failover` directory.
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Provisioned services are defined in `../docker-compose-db-failover.yml` template.
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## Set the size of DB cluster
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Default size is 2 nodes. For a 3-node cluster run: `export NODES=3` before executing any of the scripts.
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For more than 3 nodes more service definitions need to be added to the docker-compose template.
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## Set up the environment
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Run `./setup.sh`
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This script will:
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1. Start a bootstrap DB instance of MariaDB cluster
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2. Start additional DB instances connected to the bootstrapped cluster
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3. Stop the bootstrap DB instance
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4. Optionally start Keycloak server
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Parameterized by environment variables:
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- `MARIADB_HA_MODE` See: [MariaDB HA parameters](https://mariadb.com/kb/en/library/failover-and-high-availability-with-mariadb-connector-j/#failover-high-availability-parameters)
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Defaults to `replication`.
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- `MARIADB_OPTIONS` See: [MariaDB HA options](https://mariadb.com/kb/en/library/failover-and-high-availability-with-mariadb-connector-j/#failover-high-availability-options).
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Use format: `?option1=value1[&option2=value2]...`. Default is an empty string.
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- `START_KEYCLOAK` Default is `false`. Use `export START_KEYCLOAK=true` to enable.
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More options relevant to MariaDB clustering can be found in `../db/mariadb/wsrep.cnf`.
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## Test the failover
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### Manual failover
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To induce a failure of specific DB node run: `./kill-node.sh X` where `X ∈ {1..3}`
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To reconnect the node back run: `./reconnect-node.sh X`
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### Automated failover loop
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Run `./loop.sh`
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This script will run an infinite loop of failover/failback of DB nodes, switching to the next node in each loop.
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Parameterized by environment variables:
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- `TIME_BETWEEN_FAILURES` Default is `60` (seconds).
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- `FAILURE_DURATION` Default is `60` (seconds).
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To exit the script press `Ctrl+C`.
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### Check number of table rows across the cluster
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Run: `./check-rows.sh`
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## Tear down the environment
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Run `./teardown.sh`
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This will stop all services and delete the database.
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