Storage Pools - Containers
View status and access information about containers in cloud-container storage pools.
Data in a cloud-container storage pool is collected into a number of containers. A container is a
file that holds a number of data extents. In server messages, these data extents are sometimes
called
chunks. Deduplicated and non-deduplicated data extents are separated into the following types of containers:
- Deduplicated container files
- This type of container file stores deduplicated data extents. The data deduplication process
divides files into smaller data extents to identify identical extents that are already available in
the storage pool. Instead of backing up the redundant extents, the files that include identical
extents all reference the same extent. These extent references are tracked in the server
database.
During file restore operations, files can be reconstituted from data extents that are spread across multiple containers. Multiple files might require the same data extent in order to be restored.
- Non-deduplicated container files
- This type of container file stores data extents that cannot be deduplicated. Data that cannot be deduplicated includes metadata, encrypted data, and files that are too small to be effectively broken into smaller extents for data deduplication.
A cloud-container storage pool can be configured to temporarily store data in one or more local file system directories during data ingestion. Containers are first cached on disk across the file system directories, and are then uploaded to cloud storage. Temporarily storing containers on disk is designed to improve the speed of data ingestion.
The following information is available on the page:
- Name
- The location and file name of the container. If the container is still in temporary storage on disk before transfer to the cloud, the location is the file system directory path to the container file. After the container is transferred to cloud storage, the location is the path to the container within the cloud storage system.
- File Name
- The file name extension of a container indicates which kind of data extents are stored in the
container. If the file extension is
.dcf, the container stores deduplicated data extents. If the file extension is.ncf, the container stores non-deduplicated data extents. - State
- A cloud container's state indicates the container's progression within its lifecycle. When the
container is in cloud storage and still contains referenced extents, no state is displayed in this
column. Otherwise, the following states can be shown:
- AVAILABLE
- The container was created and is available in a local disk directory. The container is cached in
this directory temporarily before it is transferred to cloud storage. The container is not currently
being transferred.
If cloud data lock is enabled for the storage pool, be aware that the data lock is not yet applied. Cloud data lock uses the Write Once Read Many (WORM) capabilities of your cloud storage provider to help prevent containers from being deleted or overwritten. Because cloud data lock requires the cloud provider's WORM capabilities, containers are not locked until they are located in cloud storage.
- READONLY
- The container is being transferred from the local directory cache to cloud storage. Data can be read from the container, but data cannot be written to the container.
- PENDING
- The container has no referenced extents, but cannot be deleted from cloud storage because it is data locked. The container will be deleted after its data lock expires.
- Cloud Space
- The amount of space that the container occupies in cloud storage. This measurement includes both referenced and unreferenced extents. This measurement also includes the container header and extent headers. Contrast this total container size with the information that is shown in the Used column.
- Used
- The amount of space within the container that is used for referenced data extents. The measurement excludes extents that are no longer referenced. This measurement also excludes the container header and extent headers.
- Last Written
- The approximate date and time that data was last written to the container.
- Last Audit
- The approximate date and time that the container was last audited. By auditing a container, you can verify that it has valid content. Because multiple files might reference the same data extent, damaged extents might affect the recoverability of multiple files. If the container was not audited recently, you might want to use the AUDIT CONTAINER command to scan for inconsistencies between database information and the container. This comparison validates the integrity of the data extents within the container.
- Cloud URL
- The URL that the server uses to connect to the cloud storage system.
- Lock Expiration
- If cloud data lock is enabled for the storage pool, the container is locked to help prevent it from being deleted or overwritten. The container is locked until the date and time that is shown. The initial lock expiration is set when the server writes the container to cloud storage, and is calculated based on the storage pool's lock duration property. As more files are backed up, deduplication processing might create more references to data extents within the container. As new references are added, the container's lock expiration is recalculated based on the most-recent file that is referencing the container.