title: Loki retention period s3 + dynamo
body: <p>I have a question about the retention mechanism in grafana-loki
  I need store logs for one year and be able to query them
  Setup is in k8s with the official Loki chart</p>
  <p>below is my config</p>
  <pre><code>  auth_enabled: false
    ingester:
      chunk_idle_period: 5m
      chunk_block_size: 262144
      chunk_retain_period: 1m
      # max_transfer_retries: 0
      lifecycler:
        ring:
          kvstore:
            store: inmemory
          replication_factor: 1
    limits_config:
      enforce_metric_name: false
      reject_old_samples: true
      reject_old_samples_max_age: 168h
    schema_config:
      configs:
        - from: 2020-05-15
          store: aws
          object_store: s3
          schema: v11
          index:
            prefix: loki_index_prod_
            period: 8760h
            tags:
              env: prod-loki
    server:
      http_listen_port: 3100
    storage_config:
      aws:
        s3: s3://us-east-1/loki-prod-t
        s3forcepathstyle: true
        dynamodb:
          dynamodb_url: dynamodb://us-east-1
    table_manager:
      index_tables_provisioning:
        inactive_read_throughput: 5
        inactive_write_throughput: 5
        provisioned_write_throughput: 10
        provisioned_read_throughput: 10
      chunk_tables_provisioning:
        inactive_read_throughput: 5
        inactive_write_throughput: 5
        provisioned_write_throughput: 10
        provisioned_read_throughput: 10
      retention_deletes_enabled: true
      retention_period: 8760h
      creation_grace_period: 24h
  </code></pre>
  <p>Now retention is configured for a year, but when the retention period is exited new table in dynamodb will be created, and the old one will be immediately deleted?</p>
  <p>In this case, I will lose all logs from the previous year and start from scratch?</p>
  <p>Another aspect is how to deal with the retention of chunks in s3?</p>
  <p>Please advice ...</p>