Configure Volumes and Caches

StationOps infrastructure configurations can include shared EFS volumes and managed caches. Create these components first, then grant services access or mount a volume at the paths used by the application.

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Create a Persistent Volume

1. Open the project in Architect and edit the infrastructure configuration.
2. Add a Volume component.
3. Give the volume a descriptive name.
4. For each environment, choose its removal policy:
   • Keep preserves the EFS volume when its infrastructure component is removed.
   • Delete removes it with the infrastructure component.
5. Save the component.

StationOps volumes use Amazon Elastic File System (EFS), making the same persistent filesystem available to supported services that mount it.

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Mount a Volume in a Service

1. Create or edit the service.
2. Find the service's volume mounts.
3. Select the EFS volume.
4. Add one or more absolute paths inside the container, such as /data.
5. Save and deploy the configuration.

The application must read and write the configured container path. Mount only the services that should share the filesystem.

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Create a Cache

Add a Cache component and select one of the engines offered by Architect:

• Redis OSS for key/value data structures, optional replicas, authentication, and snapshots.
• Memcached for a distributed in-memory cache configured with a node count.

Choose the engine version, node type, port, and environment-specific capacity. The default ports are 6379 for Redis and 11211 for Memcached.

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Configure Redis

Redis provides these additional controls:

• Replicas: zero creates a single node without automatic failover; one or more creates a replication group with automatic failover and Multi-AZ.
• Authentication: None relies on VPC access, while AUTH Token creates an AWS Secrets Manager secret with a generated password.
• At-rest encryption and transit encryption settings.
• Snapshot retention for environment-level recovery requirements.
• Removal policy for each environment.

Make sure the service client supports the selected TLS and authentication settings before deployment.

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Configure Memcached

Memcached uses a node count rather than Redis replicas. Configure the node type, node count, port, transit-encryption setting, and removal policy for each environment.

Memcached does not expose the Redis authentication, at-rest encryption, or snapshot-retention controls in Architect.

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Grant Service Access

Use the cache access selector to choose the services that may read from and write to the cache. Keep the list limited to the applications that need it, then configure those applications with the connection information produced by the deployed infrastructure.

After deployment, verify connectivity from every authorised service and confirm that unauthorised services do not depend on the cache.

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Related Guide