• Configuring file systems

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    Configuring file systems

    Create a file system

    Before you begin

    Make sure there is a NAS server configured to support the NFS file system type, and that a pool exists with enough available storage space.

    Procedure
    1. Under Storage, select File > File Systems.
    2. Select the Add icon.
    3. On the Protocol window, select the Linux/Unix Shares (NFS). Then select the associated NAS server.
    4. Continue following the steps in the wizard while noting the following:
      • On the Storage page, the Thin checkbox is selected by default. If you do not want to create a thin file system, remove the checkmark from the Thin checkbox. Removing the checkmark also disables the Data Reduction option.
      • On the Storage page, select the Data Reduction checkbox to enable data reduction on the file system. Data reduction is applied on all new incoming writes. Data that already exists on the file system does not have data reduction applied. Data reduction can be enabled only on thin file systems that reside in All-Flash pools, and only for thin file systems created on Unity systems running OE version 4.2.x or later.
      • On the Shares page, optionally, configure the initial share for the file system.
      • You can configure host access and a snapshot schedule for the file system when you create the file system, or you can do this at a later time.

    Change file system properties

    If the associated NAS server is a replication destination, many configuration options cannot be changed.

    Procedure
    1. Under Storage, select File > File Systems.
    2. Select the relevant file system, and then select the Edit icon.
    3. On the General tab:
      • You can change the description of the file system and the file system size.
      • You can view the file system capacity, including used space and free space, on this tab.
      • If a thin file system was created on a Unity system running OE version 4.1, you can also change the minimum allocation size. You cannot reduce the storage size lower than the current allocation.
      • You can enable data reduction for thin file systems created on a Unity system running OE version 4.2.x or later. As data reduction is applied to all new incoming writes to a file system, data reduction statistics (such as data reduction ratio) display on the Properties page.

        If data reduction is enabled and then subsequently disabled, existing data in the file system will remain as is, but newly-written data will not have data reduction applied.

      • If data reduction is enabled, you can also enable Advanced Deduplication, which provides the ability to reduce the amount of data storage needed by eliminating redundant data from the system. Once enabled, all incoming writes to the system will have advanced deduplication applied.

        Advanced deduplication is available only on:

        • Dynamic or Traditional pools in Unity 380F, 480F, 680F, and 880F systems
        • Dynamic pools in Unity All-Flash 450F, 550F, and 650F systems
        • All-Flash pools in Unity Hybrid 380, 480, 680, and 880 systems
      • You can change capacity alarm threshold settings for when Info, Warning, and Error alert messages are generated.
    4. On the Snapshots tab, manage the file system's snapshots or configure a snapshot schedule for the file system.
    5. On the FAST VP tab, change the file system tiering policy and view the data distribution per tier.
    6. On the Advanced tab, optionally enable Events Publishing for a file system.
    7. On the Quota tab, configure or change settings for file system quotas and quota trees.
    8. On the Replication tab, configure or change the file system replication settings.
      Note:  Replication can be set on the file-system level only if the replication session already exists for the NAS server where the file system resides.
    9. On the FLR tab (FLR-enabled file systems only), optionally modify the retention periods, enable auto-lock of new files, set an auto-lock policy interval, or enable automatic deletion of files once the retention period expires.
      Note:  If the file system is a replication destination, FLR properties cannot be modified.

    About Events Publishing

    Events Publishing allows third-party applications to register to receive event notification and context from the storage system when accessing file systems by using the NFS protocols. The Events Publishing agent delivers to the application both event notification and associated context in one message. Context may consist of file metadata or directory metadata that is needed to decide business policy.

    You must define at least one event option (pre-, post-, or post-error event) when Events Publishing is enabled.

    • Pre-event notifications are sent before processing an NFS client request.
    • Post-event notifications are sent after a successful NFS client request.
    • Post-error event notifications are sent after a failed NFS client request.
    Table 1. Event descriptions
    Value
    Definition
    Protocol
    OpenFileNoAccess
    Sends a notification when a file is opened for a change other than read or write access (for example, read or write attributes on the file).
    NFSv4
    OpenFileRead
    Sends a notification when a file is opened for read access.
    NFSv4
    OpenFileReadOffline
    Sends a notification when an offline file is opened for read access.
    NFSv4
    OpenFileWrite
    Sends a notification when a file is opened for write access.
    NFSv4
    OpenFileWriteOffline
    Sends a notification when an offline file is opened for write access.
    NFSv4
    FileRead
    Sends a notification when a file read is received over NFS.
    NFSv3 or NFSv4
    FileWrite
    Sends a notification when a file write is received over NFS.
    NFSv3 or NFSv4
    CreateFile
    Sends a notification when a file is created.
    NFSv3 or NFSv4
    CreateDir
    Sends a notification when a directory is created.
    NFSv3 or NFSv4
    DeleteFile
    Sends a notification when a file is deleted.
    NFSv3 or NFSv4
    DeleteDir
    Sends a notification when a directory is deleted.
    NFSv3 or NFSv4
    CloseModified
    Sends a notification when a file is changed before closing.
    NFSv4
    CloseUnmodified
    Sends a notification when a file is not changed before closing.
    NFSv4
    RenameFile
    Sends a notification when a file is renamed.
    NFSv3 or NFSv4
    RenameDir
    Sends a notification when a directory is renamed.
    NFSv3 or NFSv4
    SetSecFile
    Sends a notification when a file security change is received over NFS.
    NFSv3 or NFSv4
    SetSecDir
    Sends a notification when a directory security change is received over NFS.
    NFSv3 or NFSv4

    Create Events Publishing notifications

    Before you begin

    Before you can set up Events Publishing for a NAS server:

    • You cannot enable Events Publishing for a NAS server that is acting as a replication destination.
    • At least one file system must exist for the NAS server.
    • You must obtain the IP addresses of the CEPA servers.
    • Ensure that NFS protocol events notifications have been enabled on the File Systems Properties Advanced window.
    Procedure
    1. Under Storage, select File > NAS Servers.
    2. Select the relevant NAS Server, and then select the Edit icon.
    3. On the Protection & Events tab, select the Events Publishing sub-tab.
    4. Select the Enable Common Event Publishing checkbox.
    5. On the New Event Pool window, specify the required items. You must configure at least one event from one of the available categories (pre-event, post-event, or post-error event).
    6. Click Configure.
    7. Optionally, select Show policy settings to configure pre-events and post-events failure policies.
    8. Optionally, select Show advanced settings to configure CEPA server options.
    9. Click Apply after you finish configuring events.

    Change Events Publishing settings

    Procedure
    1. Under Storage, select File > NAS Servers.
    2. Select the relevant NAS Server, and then select the Edit icon.
    3. On the Protection & Events tab, select the Events Publishing sub-tab.
    4. To change event pool settings, select the pool and then the Edit icon. Update any necessary information.
    5. To change event policy or connection settings, select the pool and then the relevant Show settings link. Update any necessary information.

    About automatic file system shrink and extend

    The system automatically shrinks and extends a thin file system based on capacity needs.

    Thin-provisioned file systems are automatically extended or shrunk by the system when certain conditions are met. Automatic extend prevents the file system from running out of space. Automatic shrink improves space allocation by releasing any unused space back to the storage pool. The automatic shrink and automatic extend operations are based on a high water mark (HWM) for auto-extend and a low water mark (LWM) for auto-shrink.

    For file systems smaller than 2.5 tebibytes (TiB) in size:

    • The file system is automatically extended when the used space exceeds and sustains over 75% of the allocated space. This is the fixed high water mark (HWM) for file systems less than 2.5 TiBs.
    • The file system automatically shrinks and returns space to the pool when the used space is 70% less than the allocated space. This is the fixed low water mark (LWM) for file systems less than 2.5 TiBs.

    For file systems larger than 2.5 TiBs in size, the high and low watermarks will be dynamic and operate based on the following:

    • Auto-extend will wait until nearly all of the allocated space capacity is used before extending file systems larger than 2.5 TiBs.
    • Auto-shrink will not require a large amount of capacity to be freed back to the pool as part of the shrink operation.

    For larger file systems greater than 2.5 TiBs, the maximum extend size is 1 TiB. This helps avoid over-allocation of space from the pool to that file system that may not be immediately used.

    You can set a minimum allocated size for a thin file system; automatic and manual shrink operations will not be able to reduce the size of the file system below this minimum. The default minimum allocated size for a thin file system is 3G.

    About manual file storage resource shrink and extend

    You can manually extend or shrink file systems.

    File resource shrink

    The shrink operation reduces the space the file resource uses from the pool, allowing the pool to reclaim the free, unused space from the target file resource.

    For thick-provisioned file resources, you can shrink the size of the resource and return unused space to the pool. For example, if a thick file system is shrunk from a size of 1 TB down to 500 GB:

    • The amount of used space for the resource remains the same.
    • The free space for the resource is reduced by 500 GB.
    • The total pool free space is increased by slightly less than 500 GB.
    • The pool size used for the resource is reduced to approximately 500 GB.

    The system displays a message indicating exactly how much space will be reclaimed by the pool as a result of the shrink operation.

    For thin-provisioned file resources, you can manually shrink the size of a file resource to a size that is equal to or less than the allocated size.

    Note:  For Unity systems running OE version 4.1.x, the minimum size of a thin storage resource is 3 GB. You cannot shrink a thin file resource below the size used. For Unity systems running OE version 4.2 or later, the thin file storage resource minimum allocated size option is not supported.
    File resource extend

    The manual extend operation does the following for thin- and thick-provisioned file resources:

    • For thin-provisioned file resources, increases the visible (virtual) size of the resource without increasing the actual size allocated to the resource from the pool.
    • For thick-provisioned file resources, increases the actual space allocated to the resource from the pool.
    Note:  You cannot extend a thick file resource beyond the total pool free size.

    Manually shrink or extend the size of a file storage resource

    The ability to manually shrink or extend the size of a storage resource applies to file systems. A manual shrink allows the pool to reclaim space, while a manual extend allocates more space to the storage resource.

    Note:  You can cancel a manual shrink operation, but the progress made prior to cancellation will not be reverted.
    Procedure
    1. Select a storage resource, and then click the Edit icon.
    2. In the Size field, enter the new reduced (shrink) or increased (extend) size of the storage resource.
      Note:  For Unity systems running OE version 4.1.x, the minimum size of a storage resource is 3 GB. You cannot shrink below the size used or extend beyond the total pool free size.