NetApp Flexgroup Volumes in ONTAP · PDF fileNetApp Flexgroup Volumes in ONTAP 2 ... A NetApp FlexGroup volume is a single namespace made up of multiple member volumes that are managed

NetApp Flexgroup Volumes in ONTAP
August 2017 | SL10312 Version 1.0

NetApp Flexgroup Volumes in ONTAP2 2017 NetApp, Inc. All rights reserved. NetApp Proprietary
TABLE OF CONTENTS
1 Introduction...................................................................................................................................... 3
1.1 What is a NetApp FlexGroup?................................................................................................. 3
1.2 The Value of NetApp FlexGroup.............................................................................................. 3
1.3 Lab Objectives........................................................................................................................... 4
1.4 Prerequisites.............................................................................................................................. 4
2 Lab Environment............................................................................................................................. 5
3 Lab Activities................................................................................................................................... 7
3.1 Create and Share a FlexVol Volume........................................................................................7
3.2 Create and Share a FlexGroup Volume.................................................................................14
3.3 Examine FlexVol and FlexGroup Volume Layout................................................................. 25
3.4 NFS Test - High File Count and Small Files......................................................................... 29
3.5 NFS Test - Low File Count and Large Files..........................................................................39
3.6 Viewing FlexGroup Performance with OnCommand Performance Manager..................... 42
3.7 FlexGroup File Layout............................................................................................................ 52
3.8 Resizing a Flexgroup.............................................................................................................. 56
3.9 Using Volume Move to Re-distribute Volumes Across a Cluster........................................65
3.10 Snapshot Restore..................................................................................................................69
3.11 Expanding a Flexgroup by Adding Member Volumes....................................................... 71
3.12 Using XCP to Migrate from FlexVol to FlexGroup............................................................. 78
4 References......................................................................................................................................81
5 Version History.............................................................................................................................. 82

1 IntroductionThis lab introduces you to NetApp FlexGroup volumes and illustrates the capacity, performance, and ease ofmanagement benefits that FlexGroups offer for environments facing the following storage challenges.
Very high file count. Large capacity footprint. Metadata intensive.
This lab also explains how FlexGroup volumes compare favorably to FlexVol volumes, and how to best migratedata onto them.
1.1 What is a NetApp FlexGroup?A NetApp FlexGroup volume is a single namespace made up of multiple member volumes that are managed andact like a single FlexVol volume. Files in a FlexGroup are allocated to individual member volumes, and are notstriped across volumes or nodes.
With FlexGroup volumes, a storage administrator can easily provision a massive single namespace in a matter ofseconds. FlexGroup uses constituent member volumes that work in collaboration to dynamically balance load andspace allocation evenly across all members. There is no required maintenance or management overhead witha FlexGroup volume. You simply create the FlexGroup volume and share it with your NAS clients. This designallows workloads to take advantage of more CPU threads per node, as well as being able to leverage more nodesper cluster for a single file system. The main performance gains occur during the initial ingest of files, but theyalso continue later because workloads are more evenly spread across the precious cluster resources.
1.2 The Value of NetApp FlexGroupNetApp FlexGroup volumes solve multiple problems that cannot be addressed by a single FlexVol. A NetAppFlexGroup blends the following concepts:
Capacity NetApp FlexGroup volumes provide >100TB in capacity by using multiple FlexVol volumesin concordance. Architecturally, there are no limits to how large a FlexGroup volume can grow (so longas you do not exceed the maximum number of FlexVols supported in a cluster). Additionally, the designof the NetApp FlexGroup allows for a nearly unlimited number files in a single namespace, allowing forgreater flexibility with your ONTAP storage systems.
Scalability With NetApp FlexGroup, a single namespace can live on multiple aggregates on a nodeor multiple nodes in a cluster. This provides a true scale-out file system, with the ability to add capacity,compute and network resources non-disruptively to large file systems. See TR-4571 (listed in theReferences section) for further details.
Performance NetApp FlexGroup does not just provide immense capacity by way of multipleconstituent member volumes, it also provides vastly improved performance for high metadataworkloads by allowing file ingest to occur across multiple volume affinities. By performing theseoperations in parallel, a NetApp FlexGroup can provide 2-6x the performance for certain NASworkloads.
Simplicity of Management Prior to NetApp FlexGroup, it was possible to simulate the volumeconcurrency for high metadata workloads by using FlexVol volumes and junction paths. However, thisdesign was limited to the architectural constraints of the FlexVol (100TB, and 2 billion files per volume).Creating multiple volumes and connecting them with junction paths created a file system that wasdefined and controlled by the storage administrator rather than the application owners. Additionally,managing multiple FlexVol volumes required more overhead to maintain the export policies, rules,CIFS shares, etc. NetApp FlexGroup brings the benefits of a multi-FlexVol volume architecture, whileremoving the management headaches. A FlexGroup is intended to be managed like a single FlexVolvolume.

1.3 Lab ObjectivesThe lab includes the following activities:
Steps to create a NetApp FlexGroup volume. Test NFS and SMB file creation on FlexGroup and FlexVol. View the effects of small and large files on FlexGroup volumes. Compare performance (wall clock) of migrating data to FlexVol versus FlexGroup. View FlexGroup volumes in OnCommand Unified Manager. Compare throughput, latency, IOPs and time to completion for FlexGroup vs FlexVol volumes in
OnCommand Performance Manager. Run commands to review file system layout in FlexGroup. Test snapshot creation and restores. Manage FlexGroup volumes (growing, adding members, enabling storage efficiencies). Migrate data to NetApp FlexGroup using XCP for NFS.
1.4 PrerequisitesThis lab assumes that you have a general working knowledge of NAS (both NFS and SMB), how to manageFlexVols in ONTAP using the command line and GUI, and how to run step by step commands. The lab alsoassumes that you are generally familiar with the concepts of clustered Data ONTAP.

2 Lab EnvironmentThe following diagram illustrates the environment for this lab.
Figure 2-1:
All of the servers and storage controllers presented in this lab are virtual devices, and the networks thatinterconnect them are exclusive to your lab session. While we encourage you to follow the demonstration stepsoutlined in this lab guide, you are free to deviate from this guide and experiment with other ONTAP features thatinterest you. While the virtual storage controllers (vsims) used in this lab offer nearly all of the same functionalityas physical storage controllers, they are not capable of providing the same performance as a physical controller,which is why these labs are not suitable for performance testing.
The Lab Host Credentials table provides a list of the servers and storage controller nodes in the lab, along withtheir IP address.
Table 1: Lab Host Credentials
Hostname Description IPAddress(es) Username Password
dc1 Active Directory Server 192.168.0.253Demo\Administrator
Netapp1!
jumphost Windows 20012R2 Remote Access host 192.168.0.5Demo\Administrator
Netapp1!
rhel1 RHEL 6.8 x64 192.168.0.61 root Netapp1!
ocum OnCommand Unified Manager 7.1 192.168.0.71 admin Netapp1!
opm OnCommand Performance Manager 7.1 192.168.0.72 admin Netapp1!
cluster1 ONTAP 9.1 cluster 192.168.0.101 admin Netapp1!
The Preinstalled NetApp Software table lists the NetApp software that is pre-installed on the various hosts in thislab.

Table 2: Preinstalled NetApp Software
Hostname Description
jumphostData ONTAP DSM v4.1 for Windows MPIO, Windows Unified Host Utility Kitv7.0.0, NetApp PowerShell Toolkit v4.3.0
ocum OnCommand Unified Manager 7.1

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NetApp Flexgroup Volumes in ONTAP · PDF fileNetApp Flexgroup Volumes in ONTAP 2 ... A NetApp FlexGroup volume is a single namespace made up of multiple member volumes that are managed