Understanding PowerMax File for storage systems

Network-attached storage is a file-level storage architecture that makes stored data more accessible to networked devices.

A storage system running PowerMaxOS 10 (6079) with embedded Unisphere supports software-defined network-attached storage (PowerMax File).

PowerMax File support a file services architecture that provides a reliable, high performance, highly available, and highly scalable system. PowerMax File runs as a container instance inside each file guest offering based on the customer configuration. File fully automates its storage provisioning. For the given Filesystem and its size, the File platform automates the provisioning, masking of PowerMax volumes. File uses SnapVX for snapshots and SRDF/S or SRDF/A for synchronous or asynchronous replication support.

Before starting the configuration process, it is recommended that you gather and record configuration information as described in the following: Configuration information, Setup Network worksheet, Setup NAS Server worksheet, Filesystem worksheet, and Create an SMB share worksheet.

Unisphere in the Embedded Element Manger (EEM) manages a single instance of PowerMax File that is present locally. The Unisphere that is installed on an external host does not manage any PowerMax File instances.

PowerMax File uses virtualized Network-Attached Storage (NAS) servers that use the SMB, NFS, and FTP protocols to catalog, organize, and transfer files within file system shares and exports.

A NAS server, the basis for multi-tenancy, must be created before you can create file-level storage resources. NAS servers are responsible for the configuration parameters on the set of file systems that it serves.

Network File System (NFS) is an access protocol that enables users to access files and folders on a network. You can create an NFS export to make file system paths on your storage system available for mounting by NFS clients.

Server Message Block (SMB) is an access protocol that allows remote file data access from clients to hosts on a network. An SMB share, also known as an SMB file share, is a shared resource on an SMB server.

Virtual LAN (VLANs) are supported for File services. A virtual VLAN is a subnetwork which can group different devices which are in separate physical LANs. VLAN tags are used to identify a group of allowed networks. The 1VLAN id can be between 1 through 4095. The numbers of VLANs that are supported per port are 32.

Jumbo frames are supported for File services. A jumbo frame is an Ethernet frame with a payload greater than the standard maximum transmission unit (MTU) of 1,500 bytes.

Services such as anti-virus, scheduled snapshots, and Network Data Management Protocol (NDMP) backups ensure that the data on the file systems is well protected.

File supports 3-way NDMP and all backup software supporting NDMP can be used for backup. File also supports the Dell VSI plug-in for VMware.

The following are some configuration limits:

  • Max FS Count (two nodes) - 2048
  • Max FS Count (more than two nodes) - 4096
  • Max FS Size - 64 TB
NOTE: The File system count includes checkpoint snapshots.

File is a highly available platform. For each File node, there exists a backup node and also supports heterogeneous networking. File nodes need not have same SLIC type or number of SLICs and each node can have different subnets. However, the node denoted as ‘Backup Node’ for a NAS Server is expected to have the same subnets as its primary.

File fully automates storage provisioning. For the given Filesystem and its size, the File platform automates the provisioning and masking of PowerMax volumes. File uses SnapVX for snapshots and SRDF/S or SRDF/A for synchronous or asynchronous replication support.

PowerMax File leverages SRDF and enables both synchronous and asynchronous replication modes at NAS server level. It has a fully automated storage provisioning on the destination and allows replicating snapshot policies.

SRDF synchronous (SRDF/S) - SRDF/S replication maintains a real-time copy at arrays that are located within 200 kilometers. The local array acknowledges writes from the production host when they are written to cache at the remote array.

SRDF asynchronous (SRDF/A) - SRDF/A replication maintains a dependent write-consistent copy at arrays at unlimited distances. The local array immediately acknowledges writes from the production host, and, therefore, replication has no impact on host performance. Data at the remote array is typically only seconds behind the primary site.

At least 2 SRDF ports need to be used for better performance.

Common Event Enablers (CEE) is an externally deployable software from Dell (primarily on Windows). This software has two packages - Common anti-virus Agent (CAVA) and Common Event Publishing Agent (CEPA). CAVA provides an anti-virus solution to clients using a NAS server. It uses an industry-standard SMB protocol in a Windows Server environment. CAVA uses third-party anti-virus software to identify and eliminate known viruses before they infect files on the storage system. The CEE CEPA ecosystem consists of dozens of applications that are designed to process SMB and NFS file and directory event notifications. See View NAS server details and Configure Events Publisher.

You can enter any subnet mask and IP combination. It is your responsibility to have the similar configuration at switch side and primary/backup nodes to have seamless IOs. You do not need to worry about assigning correct subnets in the beginning. The network can be narrowed or widened up without impact. In addition, there is increased flexibility with regards to multitenancy as different VLANs can share the same physical port on the PowerMax regardless of the subnet.

PowerMax File supports TLS1.3.

PowerMax File provides migration support for SMB2 on the source side.

See File Migration - Known issues for the list of File known issues.

The high-level sequence of tasks to configure PowerMax File for storage systems running PowerMaxOS 10 (6079) is as follows:

  1. Configure bond device.
  2. Create NAS server (a NAS server is required in order to create a file system).
  3. Create File Systems (file systems enable you to partition data for your users).
  4. Protect File Systems (optionally protect file system data using snapshots or replication).

The detailed sequence of tasks to configure PowerMax File is as follows:

  1. View node inventory (under System > File Configuration> Node Inventory tab)— View file node inventory.
  2. Configure bond devices (under System > File Configuration> Network Devices tab)— View file system network devices.
  3. Create and configure NAS servers (under Storage > File)— View NAS servers. Other properties and controls that are associated with NAS servers are in the following tabs:
  4. Create and configure file systems (under Storage > File)— View file systems. Other properties and controls that are associated with file systems are in the following tabs:
    • Details— View file system details
    • Snapshots— View file system snapshots. Snapshots can be used for restoring individual files or the entire file system back to a previous point in time.
    • User Quotas— View file system snapshots. Quota management allows you to place limits on the amount of space that can be consumed in order to regulate file system storage consumption. User quotas are set at a file system level and limit the amount of space a user may consume on a file system.
    • Tree Quotas— View file system tree quotas. Quota management allows you to place limits on the amount of space that can be consumed in order to regulate file system storage consumption. Quota trees limit the maximum size of a directory on a file system. Unlike user quotas, which are applied and tracked on a user-by-user basis, quota trees are applied to directories within the file system.
    • File Level Retention— View and modify file level retention properties. When a snapshot is created, it can be configured to have no automatic deletion or retention until a specific date and time. If retention is set, the snapshot is automatically deleted upon reaching the retention date. The retention setting does not prevent the snapshot from being deleted before the retention date.
  5. Create and configure SMB Shares (under Storage > File > SMB Shares)— View SMB shares.
  6. Create and configure NFS Exports (under Storage > File > NFS exports)— View file components NFS exports. You can create an NFS export to make file system paths on your storage system available for mounting by NFS clients.
  7. Create Global Namespaces (under Storage > File > Global Namespaces)— View global namespace servers.
  8. Create and configure snapshot policies (under Data Protection > File Protection> Snapshot policies)— View file protection snapshot policies.
  9. Create and configure File replication (under Data Protection > File Protection > Replication. Pre-requisities for File replication are:
    • To create the initial RDF group, use the “symrdf addgrp” command. The CLI command is documented in the Solutions Enabler SRDF Family CLI User Guide.
    • To update the Remote Machine Table for Gige use the “symcfg -rmt” create command. This is documented in theSolutions Enabler Array Controls and Management CLI User Guide.
    File replication uses SRDF to facilitate remote replication in Synchronous and Asynchronous modes at NAS server level. Properties and controls that are associated with replication are:

Migration support is provided for file objects, system configuration and user data from eNAS to PowerMax FileThe sequence of tasks to migrate from eNAS to PowerMax File is as follows:

  1. Set up File migration network for data import (under System > File Migration > Network tab)— View File migration network.
  2. Add the remote (source system) (under System > File Migration > Remote Systems tab). If the source system does not appear in PowerMax, add the information needed to discover and access the source system (to establish the import connection).
  3. Select the NAS server (VDM) to import.
  4. Set up File migration management connection to the remote storage system (under System > File Migration > Remote Systems tab)— View remote systems and Add remote storage system.
  5. Set up File migration sessions by importing sessions from the remote source NAS server (under Data Protection > File Migration > File Imports)— Import NAS servers from source array and View and manage file import sessions .

The state transitions for File migration are outlined in the following diagram and tables.

State transition diagram

Table 1. File migration state transitions
State Name Resume Pause Cutover Commit Cancel Modify
1 Initialized Allowed - - - Allowed Allowed
2 Initial_Provisioning - - - - Allowed Allowed
3 Initial_Copy - Allowed - - Allowed -
4 Importing_Config - - - - Allowed Allowed
5 Ready_to_Cutover Allowed* - Allowed - Allowed Allowed
6 Cutting_Over - - - - Allowed -
7 Incremental_Copy - Allowed - - Allowed -
8 Ready_to_Commit - - - Allowed Allowed -
9 Committing - - - - - -
10 Completed - - - - - -
11 Cancelling - - - - - -
12 Canceled - - - - - -
13 Error Allowed** Allowed** Allowed** Allowed** Allowed** Allowed**
14 Pausing - - - - Allowed -
15 Paused Allowed - - - Allowed -

* If repeatConfigImport is true.

** See the following table

Table 2. File migration state transitions for State ID 13
State ID State Name Stage Name Resume Pause Cutover Commit Cancel Modify
13 Error 1 Initialized Allowed - - - Allowed Allowed
13 Error 2 Initial_Provisioning Allowed - - - Allowed Allowed
13 Error 3 Initial_Copy Allowed Allowed - - Allowed -
13 Error 4 Importing_Config Allowed - - - Allowed Allowed
13 Error 5 Ready_to_Cutover Allowed* - Allowed - Allowed Allowed
13 Error 6 Cutting_Over - - Allowed - Allowed -
13 Error 7 Incremental_Copy Allowed Allowed - - Allowed -
13 Error 8 Ready_to_Commit - - - Allowed Allowed -
13 Error 9 Committing - - - Allowed - -
13 Error 10 Completed - - - - - -
13 Error 11 Cancelling - - - - Allowed -
13 Error 12 Canceled - - - - - -

* If repeatConfigImport is true.