Storage Configuration Best Practices for SAP HANA TDI on ... · EMC UNITY STORAGE SYSTEMS August...

STORAGE CONFIGURATION BEST PRACTICES FOR SAP HANA TDI ON DELL EMC UNITY STORAGE SYSTEMS

August 2017

ABSTRACT

This solution guide describes storage best practices for SAP HANA in Tailored

Data Center (TDI) deployments on Dell EMC Unity-certified enterprise storage

family systems. The solution enables customers to use Dell EMC Unity for

SAP HANA TDI deployments in a fully supported environment with their

existing data center infrastructures, providing multiple benefits.

H15220.2

SOLUTION GUIDE

Copyright

2 Storage Configuration Best Practices for SAP HANA TDI on Dell EMC Unity Storage Systems

The information in this publication is provided as is. Dell Inc. makes no representations or warranties of any kind with respect to the information in this publication, and specifically disclaims implied warranties of merchantability or fitness for a particular purpose.

Use, copying, and distribution of any software described in this publication requires an applicable software license.

Copyright © 2017 Dell Inc. or its subsidiaries. All Rights Reserved. Dell, EMC, and other trademarks are trademarks of Dell Inc. or its subsidiaries. Intel, the Intel logo, the Intel Inside logo, and Xeon are trademarks of Intel Corporation in the U.S. and/or other countries. Other trademarks may be the property of their respective owners. Published in the USA 08/17. Solution Guide, H15220.2.

Dell EMC believes the information in this document is accurate as of its publication date. The information is subject to change without notice.

Contents


Contents

Executive summary ....................................................................................................................... 4

Introduction ................................................................................................................................... 6

Technology overview and considerations................................................................................... 7

Storage design recommendations for Dell EMC Unity arrays for SAP HANA ........................ 16

Configuring Unity storage for HANA using Dell EMC Unisphere for Unity ............................. 24

Accessing Unity storage from the SAP HANA nodes ............................................................... 41

Conclusion................................................................................................................................... 45

References ................................................................................................................................... 46

Executive summary


Executive summary

SAP HANA is an in-memory platform that can be deployed locally (on-premises) or in the

cloud. It is a revolutionary platform that is ideally suited for performing realtime analytics

and developing and deploying realtime applications. At the core of this realtime data

platform is the SAP HANA database.

As Figure 1 shows, SAP HANA can be deployed on-premises in two different models:

Appliance model

Tailored Datacenter Integration (TDI) model

Figure 1. SAP HANA appliance model versus the TDI model (picture © SAP SE)

SAP HANA combines SAP software components that are optimized on proven hardware

provided by SAP hardware partners. An SAP HANA appliance includes integrated

storage, compute, and network components by default. The entire appliance is certified by

SAP, built by one of the SAP HANA hardware partners, and shipped to customers with all

software components preinstalled, including the operating systems and the SAP HANA

software. The TDI approach provides more flexibility than the appliance deployment

model; the SAP HANA servers must still meet the SAP HANA requirements and be

HANA-certified by SAP, but the network and storage components can be shared across

multiple applications. Customers can use their existing enterprise storage arrays and

integrate SAP HANA seamlessly into existing data center operations, such as disaster

recovery (DR), data protection, monitoring, and management, to reduce the time-to-value,

risk, and costs of an overall SAP HANA adoption.

Dell EMC™ Unity™ x50F and x00(F) all-flash and hybrid arrays meet all performance and

functional requirements for SAP HANA and are certified by SAP. This certification enables

customers to use Dell EMC Unity for SAP HANA TDI deployments in a fully supported

environment using their existing data center infrastructures.

Using the SAP HANA hardware configuration check tool (hwcct), Dell EMC performed

extensive testing on the Unity storage family systems in accordance with the SAP HANA-

HWC-ES-1.1 certification scenario. Based on the test results, this solution guide describes

Business case

Solution

overview

Executive summary


storage configuration recommendations for the Unity all-flash and hybrid arrays that meet

SAP performance requirements (specifically, the SAP HANA TDI key performance

indicators for data throughput and latency) and ensure the highest availability for

database persistence on disk.

Note: SAP recommends that TDI customers run the hwcct tool in their environment to ensure that

their specific SAP HANA TDI implementation meets the SAP performance criteria.

This solution guide describes SAP HANA TDI deployments in physical environments. If you plan to use SAP HANA in VMware virtualized environments on vSphere, see the VMware Virtualized SAP HANA with EMC Storage Solution Guide.

Customers using SAP HANA TDI on Unity arrays can:

Integrate SAP HANA into an existing data center

Use Unity shared enterprise storage to rely on already available, multisite concepts to benefit from established automation and operations processes

Transition easily from an appliance-based model to the Unity-based TDI architecture, while relying on Dell EMC services to minimize risk

Use their existing operational processes, skills, and tools and avoid the significant risks and costs associated with operational change

Use performance and scale benefits of Unity to obtain realtime insights across the business

Expect significant benefits using flash drives for the SAP HANA persistence by reducing SAP HANA startup, host auto-failover, and backup times

Dell EMC and the authors of this document welcome your feedback on the solution and

the solution documentation. Contact [email protected] with your

comments.

Authors: Donagh Keeshan, Fergal Murphy, Jarvis Zhu, Pete Shi, Aighne Kearney

Key benefits

We value your

feedback

http://www.emc.com/collateral/technical-documentation/h14721-vmware-virtualized-sap-hana-emc-storage-sg.pdf


mailto:Dell%[email protected]?subject=Feedback:%20Storage%20Configuration%20Best%20Practices%20for%20SAP%20HANA%20TDI%20on%20EMC%20Unity%20Storage%20Systems%20H15220.2

Introduction


Introduction

Before the SAP HANA TDI deployment model was available, customers who used the

appliance model experienced the following limitations:

Limited choice of servers, networks, and storage

Little knowledge and control of the critical components in the SAP HANA appliance

Inability to use existing data center infrastructure and operational procedures, resulting in higher infrastructure startup costs

Fixed sizes for SAP HANA server and storage capacities, leading to higher costs from lack of capacity and inability to respond rapidly to unexpected growth demands

This guide describes a solution that uses SAP HANA in a TDI deployment scenario on

Dell EMC Unity enterprise storage systems. This solution reduces hardware and

operational costs, lowers risks, and increases server and network vendor flexibility.

The guide provides configuration recommendations that are based on SAP requirements

for high availability and on the performance tests and results that are required to meet the

SAP key performance indicators (KPIs) for SAP HANA TDI.

This document provides the following information:

Best practices and tips for deploying the SAP HANA database on Dell EMC Unity all-flash and hybrid storage systems

Descriptions of the configuration requirements and storage design recommendations for Unity with SAP HANA

Steps for configuring Unity storage for SAP HANA using Dell EMC UnisphereTM for Unity

Detailed instructions for accessing Unity storage from the SAP HANA nodes

This guide is intended for system integrators, systems or storage administrators,

customers, partners, and members of Dell EMC professional services who must configure

a Unity all-flash or hybrid storage array to use in a TDI environment for SAP HANA.

Document

purpose

Scope

Audience

Technology overview and considerations



Dell EMC Unity provides customers with affordable all-flash performance solutions or

cost-effective hybrid solutions by using a midrange system that is optimized for simplicity

across the storage lifecyclethat is, simple to acquire, deploy, manage, and service. The

Unity storage system is ideally suited for midsized deployments, Remote Office/Branch

Office (ROBO) locations, and cost-sensitive, mixed-workload environments. Unity storage

is designed for all-flash arrays and is available for converged deployment, as a hybrid

system, and as a software-defined virtual edition.

Figure 2 shows the Unity product family.

Figure 2. Dell EMC Unity product family

The Unity platform is offered in two different series of models, the x00(F) and the x50F.

The x00(F) series includes the Unity 300 model and scales up to the Unity 600 model.

Customers can order and configure Unity as either an all-flash or a hybrid system. The

Unity all-flash models (300F to 600F) and hybrid models (300 to 600) are identical in form

factor and connectivity, but scale correspondingly in processing and memory capabilities.

The Unity All Flash series now includes four new models that are optimized for all-flash

performance: the x50F models, starting with the 350F and scaling to the 650F. All new

models feature additional processor cores and more system memory. The system limits

change depending on the Unity model. For more information, see the Unity Technical

Documentation data and specification sheets.

Unity uses the latest technology in multicore processors, providing greater performance

capabilities. Dell EMC recommends maximizing the use of flash drives in all Unity

systems to optimize their performance potential.

Note: Unity hybrid configurations support a maximum of 50 percent total flash capacity. If you

require more than 50 percent flash capacity, consider a Unity all-flash configuration.

Table 1 provides a detailed comparison of the Unity x00(F) models.

Table 1. Unity x00(F) models compared

Model Unity 300 Unity 400 Unity 500 Unity 600

Processor Intel E5-2603 6c/1.6Ghz

Intel E5-2630 8c/2.4GHz

Intel E5-2660 10c/2.6GHz

Intel E5-2680 12c/2.5Ghz

Memory 24 GB / SP 48 GB / SP 64 GB / SP 128 GB / SP

Dell EMC Unity

system overview

https://www.emc.com/en-us/documentation/unity-family.htm

https://www.emc.com/en-us/documentation/unity-family.htm



Model Unity 300 Unity 400 Unity 500 Unity 600

Max Drives 150 250 350 500

Max Capacity (Raw)

1.5 PB 2.5 PB 3.5 PB 5.0 PB

Table 2 provides a detailed comparison of the Unity x50F models

Table 2. Unity x50F models compared

Model Unity 350F Unity 450F Unity 550F Unity 650F

Processor 2*6-core, 1.7GHz 2*10-core, 2.2GHz 8c/2.4GHz

2*14-core, 2.0Hz 10c/2.6GHz

2*14-core, 2.4GHz12c/2.5Ghz

Memory 48 GB / SP 64 GB / SP 128GB / SP 256 GB / SP

Max Drives 150 250 500 1000

Max Capacity (Raw)

2.4 PB 4.0 PB 8.0 PB 16.0 PB

As a fully unified storage array, Unity offers both block and file provisioning in the same

enclosure. Disks are provisioned into storage pools that can host both block and file data.

Connectivity is offered for both block and file protocols.

Block connectivityUse iSCSI or Fibre Channel to access LUNs, consistencygroups, VMware datastores, and VMware virtual volumes.

File connectivityNetwork-attached storage (NAS) servers can hostfile systems that are accessed using server message block (SMB) sharesor network file system (NFS) shares. NAS servers can also host VMware NFSdatastores.

Traditional storage pools

All storage resources are provisioned from storage pools. A storage pool is a collection of

physical disks that are arranged into an aggregate group, with some form of RAID applied

to the disks to provide redundancy. Traditional storage pools apply RAID protection to

discrete groups of drives within the storage pool.

On a hybrid system, storage pools can consist of disks of varying types. These disks are

sorted into one of three tiers: extreme performance (flash), performance (SAS), and

capacity (NL-SAS). For hybrid systems with a fully automated storage tiering for virtual

pools (FASTTM VP) license, you can configure a storage pool to contain multiple tiers of

disks. This is known as a heterogeneous storage pool. When combined with FAST VP,

heterogeneous storage pools can provide efficient balancing of data between tiers without

requiring user intervention. Storage pools can also contain a single tier of disks; this is

known as a homogeneous storage pool.

Figure 3 shows the different storage pool configurations.

Storage

provisioning



Figure 3. Storage pool configurations

Each tier in a storage pool can have a different RAID configuration set. Another

consideration for storage pools is the “hot spare policy.” The Unity system reserves one

spare drive per 31 drives to serve as a spare for the system. A spare drive can replace a

faulted drive in a storage pool if it matches the drive type of the faulted disk. Any unbound

drive can serve as a spare, but Unity enforces the “1 per 31” rule.

Note: Dell EMC recommends that a storage pool always has at least 10 percent free capacity to

maintain proper functioning.

Dell EMC recommends using fewer storage pools within Unity systems to reduce

complexity and increase flexibility. It might be appropriate to configure multiple storage

pools to:

Separate workloads with different I/O profiles

Separate pools where FAST cache is and is not active

Dedicate resources to meet specific performance goals

Separate resources for multitenancy

All-flash pools

All-flash pools provide the highest level of performance in Unity systems. Use an all-flash

pool when the application requires the highest storage performance at the lowest

response time. SAS Flash 3 or SAS Flash 4 drives are preferred for all-flash pools, as

they provide higher capacities and lower cost per GB.

Dell EMC recommends using only a single drive size and a single RAID width within an

all-flash pool. You can use 1.6 TB SAS Flash 3 or SAS Flash 4 drives and configure them

all with RAID 5 8+1, for example.

Hybrid pools

Hybrid pools contain more than one type of drive technology. In addition to flash drives,

hybrid pools can contain SAS or near-line SAS (NL-SAS) drives. Hybrid pools typically

provide greater capacity at a lower cost than all-flash pools, but with lower overall

performance and higher response times. Use hybrid pools for applications that do not

require consistently low response times, or that have large amounts of mostly inactive

data.



Note: Dell EMC recommends provisioning a flash tier in hybrid pools. The minimum

recommended flash capacity is approximately five percent of the pool capacity. For more

information, see the Dell EMC Unity: Best Practices Guide.

Dynamic pools

In Unity All Flash models running OE version 4.2.x or later, all new pools created in the

Unisphere GUI are dynamic pools. New pools created in the Unisphere CLI and REST

API are dynamic pools by default.

Note: Dynamic pools are only supported on Unity All Flash models with Unity OE version 4.2 and

later. For Unity All Flash models running OE version 4.2.x or later, you can create traditional pools

using the Unisphere CLI or REST API.

Dynamic pools implement advanced RAID technology. When creating a dynamic pool in

Unisphere, the user selects the required RAID type. The RAID width is automatically

selected by the system and depends on the number of drives selected at the time of pool

creation.

Table 3 shows the relationship between the RAID type, the RAID width, and the minimum

number of drives required to create the pool. Table 3 shows only the smallest RAID

widths supported and the minimum number of drives required to create them. For

example, the smallest RAID 5 RAID width that the system supports is a 4+1. The smallest

dynamic pool created with the RAID 5 4+1 configuration is six drives. The minimum drive

count includes the number of drives specified in the RAID width, plus an extra drive to

satisfy the spare space requirements.

Table 3. RAID requirements for dynamic pools

RAID type RAID width Minimum number of

drives How it is calculated

RAID 5 4+1 6 (4+1) +1 extra drive

RAID 6 4+2 7 (4+2) +1 extra drive

RAID 1/0 1+1 3 (1+1) +1 extra drive

Note: For more information, see the Dell EMC Unity: Dynamic Pools Overview.

Unlike traditional pools, dynamic pools do not require dedicated hot spare drives. Instead,

space within each pool is reserved and can only be used to replace a failing or failed

drive. After a dynamic pool is created and the drives are partitioned into drive extents, a

number of drive extents are reserved and marked as spare space extents.

Dynamic pools have the following advantages over traditional pools:

Drives are not wasted, because there are no fixed spares. All drives in the

system can be added to a pool. This prolongs the life of the drives in the pool,

because the load is spread across additional drives.

Rebuild times are usually much faster than with traditional pools. Because spare

capacity for a dynamic pool is spread across multiple drives rather than

https://support.emc.com/docu69891_Dell_EMC_Unity:_Best_Practices_Guide.pdf

https://support.emc.com/docu85573_Dell-EMC-Unity:-Dynamic-Pools---Overview.pdf?language=en_US



concentrated in on a single hot spare drive, more drives contribute to the

rebuilding process when a drive fails.

Pools can usually be expanded based on the capacity required. For example,

you can add one drive at a time to a dynamic pool, providing provisioning

flexibility and cost savings.

RAID protection

Unity applies RAID protection to the drives in a storage pool to protect user data against

drive failures. The available RAID types are:

RAID 1/0―Provides the highest level of performance from a given set of drive resources, with the lowest CPU requirements. Only 50 percent of the total drive capacity is usable. This RAID type is best suited for applications with fast or high processing requirements.

RAID 5―Provides the best usable capacity from a set of drive resources, but with lower overall performance and availability than RAID 1/0. RAID 5 is best suited for transaction processing.

RAID 6―Provides better availability than RAID-5 and better usable capacity

than RAID 1/0, but has the lowest performance potential of the three RAID

types. It is best suited for read-biased workloads, such as archiving and

backup to drive.

FAST VP

FAST VP is an automated feature that optimizes disk utilization. It ensures that your data

is distributed effectively across the various media types in a multi-tier pool. FAST VP

defines three tiers of drive types:

Extreme performance tierFlash disks

Performance tierSerial-attached SCSI (SAS) disks

Capacity tierNL-SAS disks

When a storage pool with multiple tiers is created on a hybrid Unity system with licensed

FAST VP, block and file resources created on that storage pool are subject to FAST VP

policies. FAST VP policies can specify where to place the initial data populated to a

storage resourcethe highest tier or the lowest tier. As the data is manipulated, FAST VP

relocates data across the tiers based on usage, as shown in Figure 4.



Figure 4. FAST VP relocation

Data that is accessed frequently is placed on the best-performing tier, while less-

frequently accessed data is moved to the high-capacity tiers. Data relocation is at a 256

MB granularity and can be a scheduled recurring event. Combined with FAST cache and

the other multicore optimizations, FAST VP ensures that your disks are used efficiently.

Table 4 describes the FAST VP tiering policy settings, which are defined at the data-

resource level. This policy defines both the initial tier placement and the ongoing

automated tiering of data during data relocation operations. When creating a FAST VP-

enabled storage pool, use the highest available tier for the data volumes on flash and auto

tier for the log volumes on SAS.

Table 4. Tiering policy information

Tiering policy Corresponding initial tier placement Description

Start High then Auto-Tier (default)

Highest available tier Recommended setting. Sets the initial data placement to the highest-performing disks with available space, and then relocates portions of the storage resource's data based on I/O activity.

Auto-Tier Optimize for pool performance Sets the initial data placement to a system-determined optimum setting, and then relocates portions of the storage resource's data based on the storage resource's performance statistics such that data is relocated among tiers according to I/O activity.



Tiering policy Corresponding initial tier placement Description

Highest Available Tier

Highest available tier Sets the initial data placement and subsequent data relocation (if applicable) to the highest-performing disks with available space.

Lowest Available Tier

Lowest available tier Sets the initial data placement and subsequent data relocation (if applicable) to the most cost-effective disks with available space.

The Unity platform offers a range of storage efficiency features that can help you

maximize the utilization and performance of your system. Unity’s operating environment

was built with the capability of multicore processors and their increasing scale in mind.

With the use of flash media in hybrid array configurations, FAST cache and FAST VP can

ensure that data is readily accessible and is being stored in the proper location on the

array. Lastly, host I/O limits can be implemented to manage host activity and control

“noisy neighbors.”

Multicore optimization

A set of multicore optimizations is offered on the Unity system:

Multicore cacheWith multicore cache, read and write cache space is shared and dynamically manipulated based on the read/write activity served by the system. This ensures a proper distribution of cache resources to best serve incoming requests. The arrival rates of incoming requests are tracked and weighed against the ability of the back-end disks to write the data out of cache. Based on this information, multicore cache throttles arrival rates to avoid forced flushing. Multicore cache is fully automated. No user interaction is required to enable or manipulate the cache.

Multicore RAIDMulticore RAID manages the RAID-based protection on storage pools. With multicore RAID, any unassigned disks are marked as potential spares for use in the event of a drive fault. If a drive becomes faulted, a potential spare is selected and becomes a permanent part of the RAID group. Multicore RAID can also move a disk within the physical locations of a system. For example, a disk can be moved from one enclosure to another to better balance activity between enclosures and buses. Both assigned and unassigned disks can be relocated within a five-minute window. Note that moving an assigned disk temporarily results in a degraded RAID group. Lastly, RAID 6 groups that suffer double drive failures employ a parallel rebuild to restore full redundancy as quickly as possible. Spares are selected and the rebuild process begins immediately following a drive fault.

NAS servers

NAS servers host file systems on the Unity storage system. NAS servers use virtual

interfaces to enable host connectivity to SMB, NFS, and multiprotocol file systems, as well

as VMware NFS datastores and VMware Virtual Volumes. Depending on what is enabled

on the NAS server, SMB file systems and NFS file systems can be created either

separately or in a multiprotocol configuration. File systems and virtual interfaces are

Storage

efficiency

Unity file

systems



isolated to a single NAS server, allowing for multitenancy over multiple NAS servers. NAS

servers are hosted on a storage processor, and automatically fail over if the SP becomes

faulted. Any associated file systems also fail over.

File systems

File systems are file-based storage resources that are hosted on NAS servers. They are

accessed through shares, which can be provisioned for SMB or NFS access, providing

access for Windows or UNIX hosts. Depending on what protocol is selected for your file

system, only shares of that type can be provisioned. For example, if an SMB file system is

created, SMB (not NFS) shares can be provisioned. To provision both SMB and NFS

shares from a file system, use a multiprotocol file system.

File systems can be extended and shrunk in size, and allocated space is automatically

taken and reclaimed based on file system usage patterns. Finally, file systems can be

configured with quotas to better regulate file system space usage. Tree quotas and user

quotas are supported on file systems, and can be used in combination.

Note: For more information about file systems, see EMC Unity: Unity File System - A Detailed

Review.

SAP HANA is an in-memory database. The data is kept in the RAM of one or multiple

SAP HANA worker hosts. All database operations (reads, inserts, updates, or deletes) are

performed in the main memory of the host. This feature differentiates SAP HANA from

traditional databases, where only a part of the data is cached in RAM and the remaining

data resides on disk.

To ensure that the SAP HANA database can always be restored to its most recent

committed state, persistent storage is used to provide a fallback in case of failure. The log

captures all changes by database transactions (redo logs), and data and undo log

information is automatically saved to disk at regular savepoints.

Scale-up versus scale-out

As an SAP-certified enterprise storage array for SAP HANA, Unity arrays can be used for

both single-host (scale-up) and multihost (scale-out) systems in TDI deployments.

In single-host environments, the database must fit into the RAM of a single server. Single-

host environments are preferred for online transaction processing (OLTP)-type workloads

such as SAP Business Suite on SAP HANA.

In multihost environments, the database tables are distributed across the RAM of multiple

servers. Multihost environments use worker and standby hosts. A worker host is an active

component that accepts and processes database requests. A standby host is a passive

component. It has all database services running, but no data in RAM. It waits for a failure

of a worker host so that it can take over its role, a process known as host auto-failover.

Because the in-memory capacity in these deployments can be quite high, scale-out SAP

HANA clusters are perfectly suited for online analytical processing (OLAP)-type workloads

with very large datasets, such as SAP Business Warehouse on SAP HANA.

HANA I/O patterns

The HANA persistent devices have different I/O patterns. See the SAP HANA Storage

Requirements White Paper for details.

SAP HANA

http://www.emc.com/collateral/white-papers/h15087-emc-unity-unity-file-system.pdf

http://www.emc.com/collateral/white-papers/h15087-emc-unity-unity-file-system.pdf

http://go.sap.com/documents/2015/03/74cdb554-5a7c-0010-82c7-eda71af511fa.html




Data volume

Access to the data volume is primarily random, with various block sizes from small

4 K blocks up to large 64 M blocks. The data is written asynchronously with parallel I/Os

to the data file system. During normal operations, most of the I/Os to the data file system

are writes, and data is read from the file system only during database restarts, SAP HANA

backups, host auto-failovers, or a column store table load/reload.

Log volume

Access to the log volume is primarily sequential, with various block sizes from 4K up to

1M blocks. SAP HANA keeps a 1 M buffer for the redo log in memory. When the buffer is

full, it is synchronously written to the log volume. When a database transaction is

committed before the log buffer is full, a smaller block is written to the file system.

Because data to the log volume is written synchronously, a low latency for the I/O to the

storage device is important, especially for the smaller 4 K block and 16 K block sizes.

Similar to the data volume, during normal database operations, most of the I/Os to the log

volume are writes, and data is read from the log volume only during database restarts,

high availability (HA) failover, and log backups or database recovery.

SAP HANA I/Os can be optimized for specific storage environments. See Optimizing file

I/Os after SAP HANA installation for a description of the specific optimization required for

the Unity arrays.

Since SAP introduced the TDI deployment model, two certification scenarios have been

used to test the performance of the SAP HANA persistence (data and log) and validate

that the storage array meets the SAP KPIs for bandwidth (MB/s) and latency

(microseconds): HANA-HWC-ES 1.0 and HANA-HWC-ES 1.1.

HANA-HWC-ES 1.1

With SAP HANA 1.0 SPS 10 and higher, SAP introduced a new scenario for enterprise

storage certifications. Version 1.1 now uses the underlying file system performance tool

(fsperf) for file system performance validation. With fsperf, random I/O operations required

additional resources and the KPIs could be achieved only with more disks (HDDs) or flash

disks.

The Unity all-flash and hybrid arrays for both the x00(F) and the x50F models

have been certified using HANA-HWC-ES 1.1. All configuration and scalability

recommendations in this document are based on this scenario. When re-

validating Unity all-flash and hybrid arrays at a customer site, see SAP Note

1943937: Hardware Configuration Check Tool - Central Note.

SAP HANA

certification for

Unity

https://service.sap.com/sap/support/notes/1943937

Storage design recommendations for Dell EMC Unity arrays for SAP HANA



SAP HANA production systems in TDI environments must meet the SAP KPIs. The

following configuration recommendations apply to SAP HANA production systems

deployed on Unity all-flash and hybrid storage arrays:

SAN connectivity

Virtual provisioning

Unity scalability

Capacity requirements

Competing workloads

This section addresses general considerations that arise when you connect SAP HANA to

Unity arrays.

Host connectivity

The SAP HANA nodes connect to the Unity arrays through a Fibre Channel SAN. SAN

components require a minimum 8 Gb/s link speed, and the SAN topology must follow best

practices for all redundant components and links.

General SAN considerations

The connectivity, which includes host HBAs, SAN ports, switches, and array front-end

ports, requires careful planning. Unity provides multiple options for front-end connectivity

through on-board ports directly on the DPE and optional I/O modules whose configuration

must match between SPs. Fibre Channel I/O module ports use 16 Gb SFPs. 16 Gb FC is

recommended for the best performance. All Fibre Channel ports can negotiate to lower

speeds.

The SAP HANA KPIs for TDI deployments require a maximum bandwidth of 400 MB/s per

SAP HANA node. If, for example, ten nodes are connected in a SAN to a Unity array, a

total bandwidth of 4000 MB/s is required. Assuming a 16 Gb/s front-end port provides

approximately 1500 MBps bandwidth, four dedicated 16 Gb/s front-end ports are

recommended to support ten SAP HANA nodes (4 x 1500 MB/s = 6000 MB/s), two on

each SP, to facilitate high availability, load-balancing, and continued connectivity in the

event of SP failure.

While this maximum bandwidth requirement is only seen in the unlikely event that all

nodes have this requirement simultaneously, it is one of the SAP HANA certification

criteria that the storage arrays must sustain this peak workload.

This requirement does not just affect the storage front-end configuration. In the example

with ten nodes, the complete path through the SAN network must be configured to

support the maximum bandwidth also.

SAN connectivity



HBA ports

Each HBA port (initiator) creates a path for I/Os between the host and the SAN switch,

which then continues to the Unity storage. If a host only uses a single HBA port, it will

have a single I/O path that serves all I/Os. Such a design is not advisable, because a

single path does not provide HA and also risks a potential bottleneck during high I/O

activity due to the lack of additional ports for load-balancing.

A better design provides each SAP HANA server with at least two HBA ports, preferably

on two separate HBAs. The additional ports provide more connectivity and also allow the

Linux DM-MPIO to load-balance and failover across HBA paths.

Unity storage processor connectivity for SAP HANA persistence

Unity is a unified array providing block and file connectivity. Even though file storage can

be used in an SAP HANA environment for different purposes (such as PXE-boot and

shared file systems), the SAP TDI certification of the Unity series array applies to block

Fibre Channel (FC)-attached SAP HANA persistence (data and log) only.

Special attention is required when you connect SAP HANA nodes to the front-end FC

ports of a Unity array. The Unity series provides flexible connectivity options through Dell

EMC UltraFlexTM I/O modules for both the file for NFS/SMB connectivity and the block

storage for FC and iSCSI host connectivity.

The block connectivity for the SAP HANA persistence requires the UltraFlex I/O FC

module (block only) on each storage processor with 4 x 16 GB/s FC ports. Each Unity

model supports up to two UltraFlex I/O modules per SP.

Each SAP HANA node must connect to a minimum of two FC ports on each storage

processor. Figure 5 shows the recommended FC port connectivity on an UltraFlex I/O

module on each storage processor.

Figure 5. Rear view of Unity DPE

To achieve full I/O performance for SAP HANA production deployments, implement the

following FC port requirements for a Unity array:

Dedicate FC ports to SAP HANA and do not share them with non-SAP HANA applications.

Never connect a single HBA to both ports of the same I/O module.

Balance FC ports used for SAP HANA across all available I/O modules.

Use 16 Gb/s FC ports (recommended). Neither 10 Gb/s iSCSI nor Fibre Channel over Ethernet (FCoE) have been validated for SAP HANA.



Unity arrays can use Dell EMC Virtual Provisioning™ to provide capacity to an application.

The capacity is allocated using Virtual Provisioning data devices and provided through

storage pools based on the disk technology and RAID type.

SAP HANA persistence (data and log) for production installations

For SAP HANA production installations, Dell EMC recommends using flash drives for the

SAP HANA persistence (data and log volumes) to meet the SAP HANA KPIs.

Using flash devices provides benefits for SAP HANA production installations as follows:

Sub-millisecond latencies for small block sizes on the log volume

Reduced SAP HANA startup times when data is read from the data volumeinto memory

Reduced SAP HANA host auto-failover times in scale-out deployments whena standby node takes over the data from a failed worker node

Reduced SAP HANA backup times when the backup process needs to readthe data from the data volume

RAID protection

Flash drives successfully meet the SAP HANA performance KPIs for the SAP HANA

persistence. Dell EMC recommends the following RAID protection for SAP HANA

production systems:

Traditional pools

Unity all-flash models with RAID 5 8+1 on the extreme performance tierfor both data and log devices.

Unity hybrid models use RAID 5 8+1 (flash) on the extreme performancetier for both data and log devices.

If there is not enough flash capacity available, you can use a

FAST VP enabled storage pool RAID 5 8+1 (flash) on the Extreme performance

tier for data devices and RAID 5 4+1 (SAS) on the performance tier for log

devices.

A single RAID group RAID 5 8+1 (flash), capable of supporting up to three SAPHANA nodes.

Dynamic pools

Supported with Unity OE 4.2 version or later on all-flash models

Dynamic pools use the largest RAID width possible with the number of drives

specified at the time of creation. Use RAID 5 for dynamic pools for both data and

log devices.

Virtual

provisioning

recommendations

and data services



Storage pools

Dell EMC recommends creating one storage pool for all SAP HANA data volumes and log

volumes in a Unity array when using both an all-flash and a hybrid model.

As of OE 4.2, for all-flash models, create one dynamic storage pool on the extreme performance tier (flash).

For hybrid models, create one traditional all-flash pool or (optionally) a FAST VP-enabled traditional storage pool across the performance tier (SAS) and the extreme performance tier (flash).

SAP HANA persistence for SAP HANA nonproduction installations on Unity hybrid models

Although the SAP performance KPIs do not apply to SAP HANA nonproduction

installations, those installations are still critical components in an overall SAP landscape.

Dell EMC recommends using the SAS drives for all SAP HANA nonproduction

installations on the Unity hybrid models when you provision storage.

SAP HANA installation (/hana/shared/) on Unity hybrid models

When using NAS in Unity arrays to provide the NFS share for the SAP HANA scale-out

systems, the NL-SAS or SAS drives are sufficient when you provision additional capacity

for the /hana/shared on the Unity hybrid models.

Operating system boot image on Unity hybrid models

Using the NL-SAS or SAS drives for the OS boot image on the Unity hybrid models is

sufficient.

Unity compression

In Unity OE version 4.1 and later, Unity compression is supported on THIN LUNs and can be enabled during the LUN creation process, or enabled and disabled at a later time. The storage compression rates achieved for the SAP HANA database are typically lower than for traditional databases. This is because the SAP HANA column store compresses automatically and optimizes the compression after any changes. For best performance, Dell EMC therefore recommends not enabling Unity compression for SAP HANA production installations. For more information on Unity compression, see the EMC Unity: Compression Overview White Paper.

Use Table 5 and Table 6 to estimate the initial number of SAP HANA production nodes

that can be connected. The guidelines in Table 5 and Table 6 are based on our

performance tests on a Unity 400 model and a Unity 350F model using the SAP hwcct

tool. The tests were executed without competing workloads.

The SAP HANA node numbers listed in Table 5 and Table 6 are an initial guideline to help

you determine the number of SAP HANA worker nodes that can be connected to the Unity

array for an existing or planned SAP HANA production environment. The actual number of

production SAP HANA nodes that can be connected in a customer environment might be

higher or lower, depending on the workload. In customer environments, use the SAP

HANA hwcct tool with scenario HANA-HWC-ES 1.1 to validate the SAP HANA

performance and determine the maximum number of SAP HANA hosts on a specified

storage array.

Unity scalability

http://www.emc.com/collateral/white-papers/h15571-emc-unity-compression.pdf




Dell EMC recommends running regular SAP HANA health checks to verify the

performance of the underlying storage environment. SAP HANA configuration mini-checks

are described in the following:

SAP Note 1969700: SQL statement collection for SAP HANA

SAP Note 1999930: SAP HANA I/O Analysis

Access to these notes requires an SAP username and password.

Table 5. Unity x00(F) models scalability for HANA production systems

Model Number of SAP HANA worker nodes

Dedicated 16 GB/s FC-ports per storage processor/array

Unity 300 / Unity 300F

5 2/4


10 3/6


12 3/6


16 4/8

Note: We determined the scalability of other Unity x00(F) models by extrapolating the Unity 400

test results using the performance characteristics of the other models.

Table 6. Scalability of Unity x50F models for SAP HANA production systems

Model Number of SAP HANA worker nodes

Dedicated 16 GB/s FC-ports per storage processor/array

Unity 350F 6 2/4

Unity 450F 12 3/6

Unity 550F 14 4/8

Unity 650F 18 5/10

Note: We determined the scalability of other Unity x50F models by extrapolating the Unity 350F

test results using the performance characteristics of the other models.

Every SAP HANA node requires storage devices and capacity for the following:

Operating system boot image

SAP HANA installation (/hana/shared)

SAP HANA persistence (data and log)

Backup

Capacity

requirements

https://launchpad.support.sap.com/#/notes/0001969700




Note: The formulas for capacity sizing in the SAP HANA Storage Requirements White Paper are

subject to change by SAP. Always check these formulas before you determine capacity

requirements.

Operating system boot image

When the SAP HANA nodes boot from a volume on Unity (boot from SAN), the required

capacity for the operating system must be included in the overall capacity calculation for

the SAP HANA installation. Every SAP HANA node requires approximately 100 GB

capacity for the operating system. This capacity includes space for the /usr/sap/

directory.

When booting from a SAN, follow the best practices in the “Booting from SAN” section of

the Dell EMC Host Connectivity Guide for Linux.

SAP HANA installation (/hana/shared/)

To install the SAP HANA binaries, as well as the configuration files, traces, and logs,

every SAP HANA node requires access to a file system mounted under the local mount

point /hana/shared/. In an SAP HANA scale-out cluster, a single shared file system is

required and must be mounted on every node. Most SAP HANA installations use an NFS

file system for this file system. Unity all-flash and hybrid arrays can provide this file system

with the NAS option. The size of the /hana/shared/ file system can be calculated using the

latest formula in the SAP HANA Storage Requirements White Paper. Version 2.10 of this

document used the following formulas for calculation:

Single node (scale-up):

Sizeinstallation(single-node= MIN(1 x RAM; 1 TB)

Multinode (scale-out):

Sizeinstallation(scale-out) = 1 x RAM_of_worker per 4 worker nodes

SAP HANA persistence (data and log)

The SAP HANA in-memory database requires disk storage to:

Maintain the persistence of the in-memory data on disk to prevent adata loss due to a power outage and to allow a host auto-failover, wherea standby SAP HANA host takes over the in-memory data of a failed workerhost in scale-out installations

Log information about data changes (redo log)

Every HANA node (scale-up) or worker node (scale-out) requires two disk volumes to

save the in-memory database on disk (data) and to keep a redo log (log). The size of

these volumes depends on the anticipated total memory requirement of the database and

the RAM size of the node. To prepare the disk sizing, SAP provides several tools and

documents, as described in the SAP HANA Storage Requirements White Paper.

Version 2.10 (February 2017) of this document provides the following formulas to

calculate the size of the data volume:

Option 1: If an application-specific sizing program can be used:


http://www.emc.com/collateral/TechnicalDocument/docu5128.pdf





Sizedata = 1.2x anticipated net disk space for data

where “net disk space” is the anticipated total memory requirement of the database plus

an additional 20 percent free space. If the database is distributed across multiple nodes in

a scale-out cluster, the “net disk space” must be divided by the number of HANA worker

nodes in the cluster. For example, if the net disk space is 2 TB and the scale-out cluster

consists of four worker nodes, then every node must be assigned a 616 GB data volume

(2 TB / 4 = 512 GB x 1.2 = 616 GB).

If the net disk space is unknown at the time of the storage sizing, EMC recommends using

the RAM size of the node plus 20 percent free space for a capacity calculation of the data

file system.

Option 2: If no application-specific sizing program is available, the recommended size of

the data volume of a given SAP HANA system is equal to the total memory required for

that system:

Sizedata = 1 x RAM

The size of the log volume depends on the RAM size of the node. The SAP HANA

Storage Requirements White Paper provides the following formulas to calculate the

minimum size of the log volume:

[systems ≤ 512GB ] Sizeredolog = 1/2 x RAM

[systems > 512GB ] Sizeredolog(min) = 512GB

Backup

HANA supports backup to a file system or use of SAP-certified third-party tools. Dell EMC

supports data protection strategies for SAP HANA backup using Dell EMC Data DomainTM

and NetWorker. Although an SAP HANA backup to an NFS file system on a Unity all-flash

or hybrid array is possible, Dell EMC does not recommend backing up the SAP HANA

database to the storage array where the primary persistence resides. If you plan to back

up SAP HANA to an NFS file system on a different Unity array, refer to the SAP HANA

Storage Requirements White Paper for details about sizing the backup file system. The

capacity depends not only on the data size and the frequency of change operations in the

database, but also on the backup generations kept on disk.

When adding workloads to the Unity system, consider the reported CPU utilization rates

as well as the capacity and IOP sizing. Brief spikes of high utilization are normal and

expected on any Unity system. The Dell EMC Unity: Best Practices Guide provides details

on sustained CPU utilization and recommended operating ranges that influence whether

the system can accept additional workloads.

In highly consolidated environments, HANA, as well as other databases and applications,

competes for storage resources. The “host I/O limits” quality of service (QoS) feature can

be used to control noisy neighbors and protect the HANA production system performance.

Host I/O limits

The ability to limit the number of IOPS serviced by the Unity system is known as host I/O

limits. Host I/O limits can be applied on LUNs, VMware vStorage VMFS datastores, and

their associated snapshots. Use host I/O limits to limit incoming host activity on the basis

Competing

workloads








of IOPS, bandwidth, or both. You can enforce limits on individual resources, or you can

share a limit among a set of resources.

Host I/O limits can be effective in consolidated environments if an overload on the storage

resources affects the performance of more critical applications, such as SAP HANA

production installations. To protect the performance of SAP HANA production systems,

consider configuring host I/O limits on LUNs, datastores of non-SAP HANA applications,

or SAP HANA nonproduction systems to limit the total IOPs or bandwidth, which might

otherwise consume a large portion of the system’s resources.

Configuring Unity storage for HANA using Dell EMC Unisphere for Unity



The Unity internal architecture eliminates complex configurations and tuning steps. You

can use Dell EMC Unisphere for Unity to complete the integral storage configuration tasks

required to:

Create the SAP HANA hosts

Create a storage pool:

Traditional pool

Dynamic pool

Create a NAS Server

Create a file system and NFS share

Create SAP HANA volumes and map the volumes to theSAP HANA nodes

Configure FAST VP

Figure 6 shows the Unisphere for Unity interface that enables you to perform these tasks.

Figure 6. Dell EMC Unisphere for Unity

Use the step-by-step instructions in the following sections as an example.

Each SAP HANA node must have two host bus adapter (HBA) ports that are zoned to the

FC ports of the Unity I/O modules.

After the SAP HANA nodes are started, if the zoning is correct, the host initiators are

visible to the Unity module.

To create an SAP HANA host:

1. Select Access > Hosts in the left panel. The Hosts page appears.

Creating a host



2. To add an SAP HANA host, click the plus sign in the upper left corner and select

Host. The Add a Host screen appears.

3. Type a name for the new SAP HANA host and (optionally) a description of

the host. Click Next.

4. On the OS and Network Address page, specify a host operating system and

network address. Although the operating system information is not required, it

allows for more specific configuration and troubleshooting instructions.

The network address (name or IP address) is required to customize access to the

NFS share. Click Next.

5. On the Select iSCSI Initiators page:

If you are using iSCSI initiators, from the list of auto-discovered initiators select the iSCSI initiators the host will use to access storage resources. If you do not find the initiator you want in the list, click Create Initiator to add it manually and then select that initiator from the list of manually added initiators. Click Next.

If you are not using iSCSI initiators, click Next.

6. On the Select Fibre Channel Initiators page, from the list of auto-discovered

initiators (shown in Figure 7), select the FC initiators that the host will use to

access storage resources.

If you do not find the initiator you want in the list, click Create Initiator to add an

initiator manually, and then select it from the list of manually added initiators. Click

Next.

Figure 7. Adding a Host – Select Fibre Channel Initiators page

7. On the Review Host Configuration page, review all the information you entered

for the SAP HANA host and then click Finish to create

the host.



A pool is a set of disks that provide specific storage characteristics for the resources that

use them. For example, the pool configuration defines the types and capacities of the

disks in the pool. For physical deployments, the pool configuration also defines the RAID

configurations.

Dell EMC recommends creating one storage pool for all SAP HANA data volumes and log

volumes in a Unity array when you are using either an all-flash model or a hybrid model.

When using the all-flash model, create one storage pool on the extreme performance tier.

When you use the hybrid model, create one traditional all-flash pool or (optionally) a FAST

VP-enabled traditional storage pool across the performance tier (SAS) and the extreme

performance tier (flash).

Note: Traditional pools are supported on all Unity models. For Unity All Flash models running OE

version 4.2.x or later, you can only create traditional pools using the Unisphere CLI or REST API.

With Unity hybrid models, traditional pools are created in the Unisphere GUI. To create an

all-flash storage pool for provisioning the HANA persistence on the Unity hybrid model:

1. Select Storage > Pools in the left panel. The Pools page appears.

2. To add a storage pool, click the plus sign in the upper left corner. The

Create Pool screen appears.

3. Enter a name and (optionally) a description of the storage pool. Click Next.

4. On the Select Storage Tiers page (shown in Figure 8), select the required tier or

tiers for the storage pool:

Extreme performance tier Provides fast access times for resources

demanding the quickest response time. Databases can achieve their best

performance when using this tier.

Performance tierProvides high, all-round performance with consistent

response times, high throughput, and good bandwidth. This tier is appropriate for

database resources accessed centrally through a network.

Capacity tier Provides high storage capacity with generally lower performance.

This tier is appropriate for storing large amounts of primarily static data (such as

video, audio, and image files) for users and applications without strict

performance requirements.

Creating a traditional

pool



Figure 8. Creating a pool – Select Storage Tiers page

5. Under Selected Tiers, change the RAID configuration, if required.

6. Click Next. The Select Amount of Storage page appears, as shown in Figure 9.

Note: Flash drives are required to successfully meet the SAP HANA performance KPIs for the

SAP HANA persistence. With a FAST VP-enabled traditional storage pool on the Unity hybrid

model, Dell EMC recommends using RAID 5 8+1 (flash) on the extreme performance tier for data

devices and RAID 5 4+1 (SAS) on the performance tier for log devices.

Figure 9. Creating a pool – Select Amount of Storage page

7. From the drop-down list, select the usable capacity required for the

storage pool. Click Next.



8. Review all the information you entered for the storage pool, as shown

in Figure 10, and then click Finish to create the storage pool.

Figure 10. Creating a pool – Review Selection page

In Unity All Flash models running OE version 4.2.x or later, all new pools created in the Unisphere GUI are dynamic pools. New pools created in the Unisphere CLI and REST API are dynamic pools by default.

Note: You cannot change the RAID type of a dynamic pool after it is created. Also, you

cannot shrink a dynamic pool or change its storage characteristics without deleting the

storage resources configured in the pool and the pool itself. You can add drives to

expand the pool.

To create a dynamic pool on All Flash models with Unity OE version 4.2 or later:

1. In the left navigation bar of the GUI, click Storage > Pools. The Pools page

appears.

2. Click the plus sign in the top left corner. The Create Pool screen appears, as

shown in Figure 11.

3. Enter a name and (optionally) a description for the new storage pool. Click Next.

Creating a dynamic

pool



Figure 11. Create Pool page

4. On the Tiers page shown in Figure 12, select Extreme Performance Tier and RAID 5 (the default) for the dynamic pool. Click Next. The Drives page appears, as shown in Figure 12.

Figure 12. Select Storage Tiers page

5. Select the number of flash drives needed to support the amount of storage required. For example, on the 350F we selected18 flash drives to support six SAP HANA nodes. Click Next.

Figure 13. Select Amount of Storage page



6. On the Review Your Selections page, as shown in Figure 14, review all the information you entered for the dynamic pool.

Figure 14. Review Your Selections page

7. If you are satisfied that the information is correct, click Finish.

Each SAP HANA node requires two volumes for persistence, one for data and one for log.

To create the SAP HANA volumes:

1. Select Storage > Block in the left panel. The LUNs page appears.

2. To create a LUN, click the plus sign in the upper left corner. The

Create a LUN screen appears.

3. Enter a name and (optionally) a description of the new LUN. Click Next.

4. On the Configure Storage Characteristics page, select the pool in which

to create the LUN.

If there are multiple tiers in the storage pool, select a tiering policy and enter the

required size of the LUN, as shown in Figure 15. Click Next.

Note: The default LUN selection is THIN. Leave Compression unchecked for SAP HANA

production installations.

Creating a

volume and

mapping to the

SAP HANA node



Figure 15. Creating a LUN – Configure Storage Characteristics screen

Note: Use SAP HANA Storage Requirements to determine the final capacity of the data and log

LUNs. In the following examples, we used 256 GB for the log LUN and 614 GB for the data LUN.

5. In the Select Host Access page, check the host that will have access to the

newly created LUN, as shown in Figure 16. Click OK.




Figure 16. Creating a LUN – Select Host Access page

6. On the Summary page, review all the information you entered for the new LUN,

as shown in Figure 17, and then click Finish to create a LUN that is visible to the

SAP HANA host.



Figure 17. Creating a LUN - Summary



FAST VP is an automated feature requiring very little manual intervention.

If sufficient flash capacity is not available, you can use a FAST VP-enabled storage pool

RAID 5 8+1 (flash) for data devices and RAID 5 4+1 (SAS) for log devices to meet the

SAP HANA performance KPIs. FAST VP enables the system to retain the most frequently

accessed or important data on fast, high-performance disks and to move the less

frequently accessed and less important data to lower-performance, cost-effective disks.

For storage pools, FAST VP:

Monitors the usage of the data in a tiered pool. Tiered pools are heterogeneous pools that are configured with multiple classes of disks (flash plus SAS or NL-SAS).

Depending on the tiering policy, uses the monitoring statistics to relocate data chunks automatically, at a 256 MB granularity, to other tiers within the pool. For

example, the Start High then Auto-Tier policy relocates data to the storage tier that is best suited for that data based on relative activity.

Performs load-balancing across the disks in tiered and non-tiered pools.

Note: FAST VP can use all supported disk types except for the SAS Flash 3 disk.

To enable FAST VP:

1. In the Unisphere GUI, click the Update System Setting in the upper right corner.

Under Software and Licenses > License Information, check that FAST VP is

licensed. If not, you must acquire a license.

2. Select Storage Configuration > FAST VP and review the settings shown in

Figure 19. You can change the Data relocation rate if required – the default

is Medium.

Enabling FAST

VP



Figure 18. FAST VP settings

3. To modify the relocation schedule, click the Modify data relocation schedule

link. The Modify data relocation schedule page appears, as shown in

Figure 19.

Figure 19. Modifying the data relocation schedule



4. Ensure that the Schedule data relocation checkbox is checked, and then select

the desired time and days to perform the data relocation. Click OK, and then

Apply.

In an SAP HANA scale-out implementation, install the SAP HANA database binaries on a

shared file system that is exposed to all hosts of a system under the /hana/shared

mount point. A NAS server can provide access to the shared HANA file systems.

To create a NAS server:

1. Select Storage > File on the left side. The File page appears.

2. To create a NAS server, first click the NAS Servers link and then click the plus

sign in the upper left corner. The Create a NAS Server screen appears.

3. Enter a server name and select a pool. Click Next. The Configure NAS Server

Address page appears, as shown in Figure 20.

Figure 20. Configure NAS Server Address

4. Enter the following information for the NAS server:

Ethernet Port

IP address

Subnet Mask/Prefix Length10

Gateway

VLAN ID

Click Next. The Configure Sharing Protocols screen appears, as shown

in Figure 21.

Creating a NAS

server



Figure 21. Configure Sharing Protocols page

5. Select the Linux/Unix shares (NFS) checkbox and enable NFSv4. Click Next.

6. (Optional) On the Unix Directory Service page, configure NIS as the UDS

for the NAS server. Click Next.

7. (Optional) On the DNS page, configure the DNS for the server. Click Next.

The Review Your Selections page shown in Figure 22 appears.

Figure 22. Review Your Selections page



8. If you are satisfied that the information is correct, click Finish to create the NAS

Server.

Ensure there is a NAS Server configured to support the file system that you want (NFS)

and a pool with enough available storage space.

To create a NAS server:

1. Select Storage > File in the left panel. The File page appears.

2. Click the File Systems link and then click the plus sign in the upper left corner.

The Configure the Protocols the File System Supports screen

appears.

3. Select the NAS Server that was previously configured for SAP HANA. Click Next.

The Provide a Name and Description page appears.

4. Enter a name and description for the file system. Click Next. The

Configure the File System Storage Characteristics page appears, as shown in

Figure 23.

Figure 23. Configure the File System Storage Characteristics page

5. Select the pool in which to create the file system, and then enter the size

of the file system required and the tiering policy requirements. Click Next.

The Configure the Initial Share page appears, as shown in Figure 24.

Creating a file

system and NFS

share



Figure 24. Configure the Initial Share page

6. Check the NFS Share (Linux/Unix) and type a name for the share.

Click Next. The Configure Access page appears.

7. To allow access to hosts, click the plus symbol in the Customize access for the

following hosts page. The Select Host Access page appears, as shown in

Figure 25.

Figure 25. Select Host Access page



8. Select the Access Type required from the list box and check the

hosts that need access to the NFS share.

Note: For the hosts to be visible, a network address must be assigned to the host.

Click OK and then click Next. The Summary page appears, as shown in

Figure 26.

Figure 26. Summary

9. Review the information you have provided. If you are satisfied that it is correct,

click Finish. The file system and NFS share are created.

Accessing Unity storage from the SAP HANA nodes



The SAP HANA 1.0 database requires Linux SUSE SLES11 or later or Red Hat RHEL 6.5

or later on the SAP HANA nodes. The SAP HANA 2.0 database requires Linux SUSE

SLES12 (or later) or Red Hat RHEL 7.5 (or later) on the SAP HANA nodes.

To access the Unity block devices from the SAP HANA nodes, ensure that zoning is correctly configured based on SAN best practices. For more information, see the Dell EMC Host Connectivity Guide for Linux.

To access the block devices from the SAP HANA nodes, first enable native Linux

multipathing. Follow the steps described in the Dell EMC Host Connectivity Guide for

Linux to enable DM-MPIO on your operating system version. Figure 27 shows an example

of a multipath.conf file.

Figure 27. Sample multipath.conf file

The SAP HANA persistent devices are visible on an SAP HANA worker host after a

restart or a rescan (using the rescan-scsi-bus.sh command). To verify that all

devices are present and that each device has the number of active paths you configured

(as shown in Figure 28, type the following command:

Multipath –ll

Figure 28. Sample Multipath -ll

Enabling native

Linux

multipathing

(DM-MPIO)







Dell EMC uses the LUN UUID to identify the correct storage devices. To view the identifier

of a Unity LUN, go to the Volume tab in the configuration workspace in the Dell EMC

Unisphere for Unity.

Note: Linux adds a preceding ‘3’ to the storage UUID.

The XFS file system provides the best performance for both SAP HANA data and log

block devices.

To format a block device with the XFS file system, run the following command on the SAP

HANA node:

$ mkfs.xfs /dev/mapper/3600601600a503e00690f195784759af8

Note: Run this command for all block devices.

If for some reason you must expand a file system, run the xfs_growfs command on the

Linux host after you expand the volume on the Unity array.

In an SAP HANA scale-out environment with worker and standby nodes, the SAP HANA

storage connector for FC (fcClient) mounts and unmounts the devices to the SAP HANA

nodes.

In addition to mounting the devices, the storage connector also writes SCSI-3 persistent

reservations (PRs) to the devices using the Linux sg_persist command. This operation,

which is called I/O fencing, ensures that only one SAP HANA worker host has access to a

set of data and log devices at a given time.

The storage connector API is controlled in the storage section of the SAP HANA

global.ini file, as shown in Figure 29. The storage section of the file contains entries

for the block devices with optional mount options. You can run the multipath –ll

command on the SAP HANA hosts to determine the worldwide identifiers (WWIDs) of the

partition entries.

Figure 29. Sample global.ini file

XFS file system

SAP HANA

storage

connector

SAP HANA

global.ini file



For information on the SAP HANA storage connector and how to configure the global.ini

file, see the SAP HANA Administration Guide and the SAP HANA Server Installation and

Update Guide on the SAP Help Portal.

Note: SAP HANA can only be installed on certified server hardware. The installation must be

performed by a certified HANA expert.

The base layer of HANA provides two file I/O interfaces:

SimpleFile―SimpleFile is used for small, simple I/O requests on configurationfiles, traces, and so on. It uses lightweight, platform-independent wrappersaround system calls.

FileFactory & File―The FileFactory & File I/O interface is used for huge,complex streams of I/O requests on the data and log volumes and for backupand recovery. It uses synchronous and asynchronous I/O operations.

The SAP HANA file I/O layer can be configured with configuration parameters to optimize

file I/Os for a given file system (the Linux XFS file system is used on all Dell EMC storage

LUNs for the SAP HANA persistence) and storage array

After the SAP HANA persistence is installed on Unity LUNs, set the following file I/O layer

parameters for optimal I/O processing after the initial SAP HANA installation has been

completed:

max_parallel_io_requests=128

async_read_submit=on

async_write_submit_blocks=all

SAP HANA 1.0

After the initial SAP HANA installation is complete, set the parameters by using the SAP

HANA hdbparam command as <sid>adm in the Linux shell:

# su - <sid>adm

# hdbparam –p # lists current parameter setting

# hdbparam –-paramset fileio.max_parallel_io_requests=128

# hdbparam –-paramset fileio.async_read_submit=on

# hdbparam –-paramset fileio.async_write_submit_blocks=all

SAP HANA 2.0

Starting with SAP HANA 2.0, the hdbparam command-line tool has been deprecated. Instead, the parameters are defined as normal parameters in global.ini > [fileio]. Set the parameter as follows in the global.ini file:

max_parallel_io_requests=128

Both async_read_submit=on and async_write_submit_blocks=all are set by

default during installation.

For more information, see SAP Note 2399079: Elimination of hdbparam in HANA 2 (access requires an SAP username and password).

Optimizing file

I/Os after SAP

HANA

installation

http://help.sap.com/hana/




Note: The previous instructions for tuning file I/O parameters are based on SAP HANA 1.0 SPS

11 and SAP HANA 2.0 SPS01. Future SAP HANA versions might allow these parameters to be

set in configuration files. See the latest SAP HANA documentation for more information.

Conclusion


Conclusion

Using SAP HANA in TDI deployments with Dell EMC Unity enterprise storage arrays

provides many benefits, including reducing hardware and operational costs, lowering

risks, and increasing hardware vendor flexibility.

All Unity flash and hybrid arrays are certified by SAP and can be used for SAP HANA

production and nonproduction installations and for single-node or scale-out systems.

Customers can now easily transition to this new architecture using SAP HANA, while

relying on Dell EMC services to minimize risk.

During our tests with SAP HANA on Unity, we observed that:

The SAP HANA-HWC-ES 1.1 certification scenario makes higher disk configuration demands than the HANA-HWC-ES 1.0 certification.

SAP HANA production installations on Unity systems require SSDs for the SAP HANA persistence to meet the SAP HANA KPIs.

Using SSDs for the SAP HANA persistence provides the following significant benefits:

Initial array and disk configuration based on capacity without the need to take spindle count into consideration.

Reduced SAP HANA startup and host auto-failover times

Reduced SAP HANA backup times

Summary

Findings

References


References

The following documentation on Dell EMC.com or Online Support provides additional

relevant information. Access to these documents depends on your login credentials. If you

do not have access to a document, contact your Dell EMC representative.

VMware Virtualized SAP HANA with Dell EMC Storage Solution Guide

Dell EMC Host Connectivity Guide for Linux

EMC Unity: Introduction to the Unity Platform - A Detailed Review

Dell EMC Unity: Best Practices Guide

EMC Unity: Compression Overview - White Paper

EMC Unity: Unisphere Overview

EMC Unity: NAS Capabilities - A Detailed Review

You can find the following SAP HANA documentation at:

https://help.sap.com/viewer/p/SAP_HANA_PLATFORM

SAP HANA Master Guide

SAP HANA Server Installation and Update Guide

SAP HANA Studio Installation and Update Guide

SAP HANA Administration Guide

Web resources

SAP HANA Storage Requirements

SAP HANA Appliance

SAP HANA One

SAP HANA Enterprise Cloud

SAP HANA Tailored Data Center Integration - Overview

SAP HANA Tailored Data Center Integration - FAQ

Note: The following documentation requires an SAP username and password.

SAP Note 1943937 - Hardware Configuration Check Tool - Central Note

SAP Note 1969700: SQL statement collection for SAP HANA

SAP Note 1999930: SAP HANA I/O Analysis.

SAP Note 2399079—Elimination of hdbparam in HANA 2

Dell EMC

documentation

SAP HANA

documentation

http://www.dellemc.com/

https://support.emc.com/




http://www.emc.com/collateral/white-papers/h15084-emc-unity-introduction-to-the-unity-platform.pdf



http://www.emc.com/collateral/white-papers/h15085-emc-unity-unisphere-overview.pdf

https://www.emc.com/collateral/white-papers/h15572-emc-unity-nas-capabilities.pdf

https://help.sap.com/viewer/p/SAP_HANA_PLATFORM

https://help.sap.com/viewer/eb3777d5495d46c5b2fa773206bbfb46/2.0.02/en-US

https://help.sap.com/viewer/2c1988d620e04368aa4103bf26f17727/2.0.02/en-US

https://help.sap.com/viewer/6b94445c94ae495c83a19646e7c3fd56/2.0.02/en-US

http://help.sap.com/saphelp_hanaplatform/helpdata/en/33/0e5550b09d4f0f8b6cceb14a64cd22/frameset.htm


http://help.sap.com/hana_appliance

http://help.sap.com/hana_one

http://www.saphana.com/entcloud

https://www.sap.com/documents/2016/05/827c26ba-717c-0010-82c7-eda71af511fa.html

https://www.sap.com/documents/2016/05/e8705aae-717c-0010-82c7-eda71af511fa.html

https://service.sap.com/sap/support/notes/1943937




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