SAP HANA database design considerations

Standard sizing type

This term refers to a sizing exercise where pre-defined configuration sizes are defined based on hardware testing and t-shirt sizing for meeting specific benchmarks to arrive at a sizing result for the hardware requirements of an SAP application (such as network, CPU, Memory, Storage).

Appliance deployment method

Supported hardware for SAP HANA depends on the deployment method. The appliance deployment method uses pre-defined validated SAP-optimized hardware by SAP-certified hardware partners that are running a specific operating system. These hardware options are offered in various configuration sizes.

Partners (such as Cloud Service Providers) offer appliances with multiple layers of redundant hardware, software and network components, which do not interrupt SAP HANA operations and defend against system outage. These components include:

• Redundant power supplies and fans and uninterrupted power supply (UPS)
• Enterprise grade error-correcting memories
• Fully redundant network switches and routers
• Disk storage systems that use batteries to guarantee writing even in the presence of power failure.
• Disk storage systems that use striping and mirroring for redundancy and recovery from disk failures.

In collaboration with SAP, a Cloud Service Provider defines the correct sizing when designing SAP-certified IaaS for SAP HANA with the appliance deployment method:

• Ensures maximum performance with the hardware capable of meeting specified workloads; providing dedicated memory for SAP HANA after the resident memory of OS and other programs is accounted for and with swapping to disk disabled.
• To maximize performance and throughput, SAP recommends that you scale up as far as possible (acquire the configuration with the highest processor and memory specification for the application workload) before scaling out (for deployments with greater data volume requirements).
• You can copy a database to machines from different SAP HANA appliance vendors with different hardware configurations, if both the source and target machines are compliant with the SAP HANA appliance specifications.

Expert sizing type

Expert sizing type refers to a sizing exercise where customer-specific data is analyzed and used to put more detail on the sizing result for the hardware requirements of an SAP application (such as network, CPU, Memory, Storage).

According to SAP, expert sizing typically includes "exploring some business processes in more detail, both on functional and technical level" (quotation source: Sizing Types - Expert Sizing).

Therefore, with expert sizing, there are no standardized tools used to conduct the sizing and it will often require significant effort and SAP expertise. Projects that use expert sizing often use an external consulting and system implementation business partner to assist the internal SAP team.

For expert sizing, the following steps are likely to be performed (source: Sizing Types - Expert Sizing):

• Identify the most important queries/apps/scenarios
• Identify, how they are used, for example, filter criteria, authorizations.
• Run these queries/apps/scenarios on representative test data (quality of test data and quantity of test data). Ideally, on a recent copy of the production data
• Measure resource consumption (CPU/memory) and response times
• Perform a forecast calculation based on the expected usage of the queries/apps/scenarios

TDI deployment method

Supported hardware for SAP HANA depends on the deployment method. The TDI deployment method uses custom-defined hardware by SAP-certified hardware partners that use flexible OS or SAP HANA versions; these can be configured to any size (under the maximum configuration tested by SAP).

Partners (such as Cloud Service Providers) offer TDI with various configuration options and redundancy options. Thes options depend on whether you select scale-up or scale-out sizing, and must be installed by an appointed SAP HANA certified administrator. These may include:

• Redundant power supplies and fans and uninterrupted power supply (UPS)
• Enterprise grade error-correcting memories
• Fully redundant network switches and routers
• Disk storage systems use batteries to guarantee writing even in the presence of power failure
• Disk storage systems that use striping and mirroring for redundancy and recovery from disk failures

SAP and a cloud service provider agree to support the customer for a selected scale-up or scale-out sizing by using SAP-certified IaaS for SAP HANA with the TDI deployment method:

• This provides different system design options regarding scale-up and scale-out variations; the SAP HANA database must then be validated before use in Production systems that use the SAP HANA Hardware Configuration Check Tool for TDI testing when requested by the SAP Support organization.
• To maximize performance and throughput, SAP recommends that you scale up as far as possible (acquire the configuration with the highest processor and memory specification for the application workload) before scaling out (for deployments with greater data volume requirements).

Networking

SAP HANA multi-node requires certain networks be in place to function. Before you order other components of your system, these networks must be set up correctly and together with the database nodes. Separation of the network flows/traffic can improve performance (that is, keeping high storage traffic separate from the user traffic) when more network interfaces are attached to the server.

As a summary of the network separation, you need in SAP HANA scale-out cluster to have:

• A client-side network, which connects the SAP Advanced Business Application Programming (SAP ABAP) application servers, SAP HANA Studio clients, and any other network client to the multi-node system. The network throughput and availability options depend on the environment and usage scenario of your SAP HANA multi-node system. Consider the amount of data transferred from and to the SAP HANA database, and the availability key performance indicators (KPIs), required for your application.
• A storage network, which connects to the Network Storage (File/NFS or Block/iSCSI dependant on infrastructure selection). The network throughput and availability options depend on the environment and usage scenario of your SAP HANA multi-node system. Consider the throughput and latency required to provide 10,000 IOPS is available to each SAP HANA node.
• An internode network for SAP HANA internal communication that is set up equivalent to the storage network. The internode network is only used for communication between nodes and the data transfer that might be required between the nodes during operations.

Within each environment is a separate networking design. The classic infrastructure environment network is the forerunner and is the most robust option of many traditional and physical networking concepts. The VPC Infrastructure environment network is a software-defined network. The IBM Power environment network (as a complementary offering from IBM Power Systems) is designed with networking principles for enterprise-grade performance.

Given these environment networks are different, configuring extra NIC throughput changes for the different infrastructure options:

• Bare Metal, on Classic Infrastructure network: To maximize performance and redundancy, the physical network interfaces (NIC) are provided with 10 Gbps and then provisioned with bonding using Link Aggregation Control Protocol (LACP). The switches are configured automatically when ordering redundancy on the physical NIC. Additional NIC cards might be added, depending on the physical machine specificiation and physical switch availability of ports.
• Intel Virtual Server, on VPC Infrastructure network: To maximize performance and redundancy, up to 5 network interfaces (vNIC) on multiple Subnets can be added.
• IBM Power Virtual Server, on IBM Power Infrastructure network: To maximize performance redundancy, multiple network interfaces (vNIC) attached to different VLANs (and their respective Subnets) can be added.
• VMware for SAP, on Classic Infrastructure network....
  • IBM Cloud for VMware Solutions, on Classic Infrastructure network: redundant adapters for VMware are set up by the VMware vSphere Distributed Switch (VDS) using either VDS on NSX-V or VDS on NSX-T, in accordance with current VMware best practices for SDDC. While subject to change, redundancy is configured by setting every distributed switch with the Route Based on Originating Virtual Port load balancing algorithm. All port groups used by the algorithm should be configured to use teamings across 2 uplinks (Active: 0,1).
  • IBM Cloud Bare Metal with VMware vSphere (manual configuration), on Classic Infrastructure network: adapters are suggested to utilise the best practices, however the vSwitch could use LACP bonding of the physical NIC adapters

Scale-out storage

Data is distributed across the multiple SAP HANA nodes, which are hosting the single database.

Follow the guidelines in Sizing SAP HANA - SAP HANA Master Guide to determine the required total storage capacity size for your target SAP HANA system.

The SAP HANA shared volume, and each of the data and log volumes, must be accessible to all nodes (which may be easier to allow network storage access to all nodes within the Subnet used for storage connectivity). There are specific performance criteria that must be met by the attached Network File System (NFS) volumes:

• /hana/data/ and /hana/log volumes, individual volumes are required for each node with a minimum of 10 IOPS/GB
• /hana/shared volume, required to be shared across all nodes with a minimum of 10 IOPS/GB and recommended to increment further to 12 IOPS/GB

For Classic Infrastructure:

• Read SAP HANA on NetApp FAS Systems with NFS) to assist configuration of your SAP HANA multi-node system.
• Use the following Network File System (NFS) mount options in /etc/fstab for each volume to mount - rw,bg,hard,timeo=600,intr,noatime,vers=4,minorversion=1,lock,rsize=1048576,wsize=1048576.

After you mount all of your volumes to all the nodes, your multi-node servers are configured and ready to install the SAP HANA multi-node database. Follow the steps in the SAP HANA Server Installation and Update Guide) to install an SAP HANA database of your required version.