Configuring tiered storage 

DSE Tiered Storage segregates hot and cold data. Configure the storage tier strategy and paths to each tier in an LCM config profile.

DSE Tiered Storage segregates hot and cold data to designated paths on different gradations of storage media, which can facilitate cost savings for data storage. Configure the storage tier strategy and paths to each tier in dse.yaml within an LCM config profile. Run an install or configure job in Lifecycle Manager to push the configuration to all applicable nodes.

After completing this procedure, additional steps are required in DSE to apply tiered storage to a table using CREATE or ALTER table statements:
CREATE TABLE ks.tbl (k INT, c INT, v INT, PRIMARY KEY (k, c)) 
WITH COMPACTION={'class':'TieredCompactionStrategy',  
    'tiering_strategy': 'DateTieredStorageStrategy', 
    'config': 'strategy1',  
    'max_tier_ages': '3600,7200'};
Configure the age policy for each tier at the schema or local node level. For more information, see configuring and testing configurations for DSE tiered storage.

Procedure

  1. Click Config Profiles from the Lifecycle Manager navigation menu.
  2. Click the edit icon for the config profile you want to edit, or click Add config profile if you have not already created a profile.
  3. In the Config Profile pane under the Cassandra section, click dse.yaml.
  4. Scroll down to the Miscellaneous pane and locate tiered_storage_options.

  5. Click + Add an item under the tiered_storage_options option.
    The Add tiered_storage_opions dialog appears.

  6. Enter a strategy_name.
    For DSE clusters to use the tiered storage strategy, the strategy must be referenced in the config of the table schema. See configuring DSE Tiered Storage in the DSE Admin documentation.
  7. Optional: Under local_options, click + Add an item to add local configuration options to overwrite the tiered storage settings in the table schema.
    Note: The class or the tiered storage configuration name cannot be overwritten. For more details and an example, see testing configurations in the DSE Admin documentation.
    The Add local_options dialog appears.

    key value fields for local_options in tiered storage

  8. Enter a key and value for each local option and click Save. For example, type max_tier_ages for key and 3600 for its value.
  9. Under tiers, click + Add an item to define the paths to the storage tiers.
    The Add tiers dialog appears.

  10. Enter the paths to the directory for each tier in the strategy and click Save.
    Tier order of each path matters. Add the paths for each tier in the order that represents each successive tier in a strategy. Each tier added is used in the order listed, with the top tier typically routing data to the fastest storage media.
    Note: Ensure the directories referenced in the path already exist. LCM does not create the directories. If the directories do not exist when the installation or configuration job runs, DSE does not start up.
    The strategy and tiers are added to the config profile.

  11. Click Save to save the Config Profile.

What's next

  • Apply tiered storage to a table schema and define the maximum age of data in each tier. See DSE Tiered Storage for complete details.
  • Go to the Clusters workspace in Lifecycle Manager and select the config profile to apply at the cluster, datacenter, or node level. Nodes can inherit config profile settings from the cluster or datacenter levels, or have settings at the node level that take precedence.
  • Run a configuration job to push the configuration to all of the applicable nodes.
  • Add dashboard graphs and alerts to monitor data distribution amongst storage tiers using the tiered storage metrics available in OpsCenter.