Azure Storage Blobs

Azure Blob Storage Lifecycle Management

Lifecycle management policies for Azure Blob Storage help you manage your data throughout its lifecycle. You can use these policies to transition blobs to cooler access tiers or to expire blobs at the end of their lifecycles. This policy is defined and applied using a JSON structure.

JSON Policy Structure

A lifecycle management policy is an array of rules. Each rule consists of a filter that selects which blobs the rule applies to, and an action that defines what to do with those blobs.

Example Policy (JSON)


{
  "rules": [
    {
      "name": "ArchiveOldBlobs",
      "enabled": true,
      "type": "Lifecycle",
      "definition": {
        "actions": {
          "version": [
            {
              "name": "archive",
              "daysAfterCreationGreaterThan": 365,
              "actionType": "MoveToArchive"
            },
            {
              "name": "delete",
              "daysAfterCreationGreaterThan": 730,
              "actionType": "Delete"
            }
          ],
          "snapshot": [
            {
              "name": "archive",
              "daysAfterCreationGreaterThan": 365,
              "actionType": "MoveToArchive"
            },
            {
              "name": "delete",
              "daysAfterCreationGreaterThan": 730,
              "actionType": "Delete"
            }
          ],
          "object": [
            {
              "name": "archive",
              "daysAfterModificationGreaterThan": 30,
              "actionType": "MoveToCool"
            },
            {
              "name": "archive",
              "daysAfterModificationGreaterThan": 365,
              "actionType": "MoveToArchive"
            },
            {
              "name": "delete",
              "daysAfterModificationGreaterThan": 730,
              "actionType": "Delete"
            }
          ]
        },
        "filters": {
          "blobTypes": [
            "block"
          ],
          "prefixMatch": [
            "container1/logs/",
            "container2/archive/"
          ]
        }
      }
    },
    {
      "name": "DeleteTempFiles",
      "enabled": true,
      "type": "Lifecycle",
      "definition": {
        "actions": {
          "object": [
            {
              "name": "delete",
              "daysAfterModificationGreaterThan": 7,
              "actionType": "Delete"
            }
          ]
        },
        "filters": {
          "blobTypes": [
            "append",
            "block"
          ],
          "prefixMatch": [
            "temp/"
          ]
        }
      }
    }
  ]
}

Policy Definition Details

rules
An array containing one or more lifecycle rules.
name
A unique name for the rule (e.g., "ArchiveOldBlobs").
enabled
Boolean value indicating whether the rule is active (true) or inactive (false).
type
Must be "Lifecycle".
definition
Contains the actions and filters for the rule.
definition.actions
Specifies the actions to be taken on blobs. Supports actions for object, version, and snapshot.
Within each action type (e.g., object), you can define multiple actions, each with a name, a condition (e.g., daysAfterModificationGreaterThan), and an actionType.
actions[*].actionType
Possible values include:
  • MoveToCool
  • MoveToArchive
  • Delete
actions[*].daysAfterCreationGreaterThan
Applies to blob versions and snapshots. Triggers action when blob version/snapshot is older than specified days from creation.
actions[*].daysAfterModificationGreaterThan
Applies to current blob objects. Triggers action when the blob's last modified time is older than specified days.
actions[*].daysAfterLastAccessTimeGreaterThan
Applies to current blob objects. Triggers action when the blob's last access time is older than specified days (requires Last-Access-Time-Tracking to be enabled).
definition.filters
Specifies criteria to select which blobs the rule applies to.
filters.blobTypes
An array of blob types to filter (e.g., ["block"], ["append"], ["block", "append"]). If omitted, applies to all blob types.
filters.prefixMatch
An array of strings representing blob prefixes. Blobs starting with any of these prefixes will be matched. (e.g., ["logs/", "archive/"]).
filters.includeBlobIndexes
An array of blob index tag conditions. Blobs with matching tags will be selected. (e.g., [{"name": "Environment", "op": "equals", "value": "Production"}]).

Key Considerations

Applying the Policy

Lifecycle policies can be applied at the storage account level through the Azure portal, Azure CLI, Azure PowerShell, or REST API. The JSON structure shown above is used when interacting programmatically.