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Every SAP HANA node requires storage devices and capacity for:
When the SAP HANA nodes boot from a volume on PowerStore (referred to as “booting 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, including space for the /usr/sap/ directory.
When booting from a SAN, follow the best practices that are described in the Dell EMC Host Connectivity Guide for Linux.
The SAP HANA in-memory database requires disk storage to:
Every SAP HANA scale-up or scale-out (worker) node requires two disk volumes or file systems to save the in-memory database on disk (data) and to keep a redo log (log). The size of these volumes or file systems depends on the anticipated total memory requirement of the database and the RAM size of the node. To help you prepare the disk sizing, see the SAP HANA Storage Requirements white paper that is attached to SAP Note 1900823: SAP HANA Storage Connector API. (Access to the note requires SAP login credentials.) The size of the data and log devices depends on the database size. Version 2.10 of the white paper provides the following formula to calculate the size of the data volume:
Sizedata = 1.2 x anticipated net disk space for data
where anticipated 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, divide the anticipated net disk space by the number of SAP HANA worker nodes in the cluster. For example, if the anticipated net disk space is 2 TB and the scale-out cluster consists of four worker nodes, every node must be assigned a 616 GB data volume:
(2 TB / 4 = 512 GB x 1.2 = 616 GB).
If the anticipated net disk space is unknown at the time of the storage sizing, use the RAM size of the node plus 20 percent free space for a capacity calculation of the datafile system.
Sizedata = 1 x RAM
Note: The preceding calculations are based on in-memory data (hot data). If you are deploying SAP HANA NSE, the size of the data volume must increase with the size of the buffer cache and anticipated warm data.
The size of the log volume depends on the RAM size of the node. The SAP HANA Storage Requirements white paper that is attached toSAP Note 1900823: SAP HANA Storage Connector API provides the following formulas to calculate the minimum size of the log volume:
[systems ≤ 512 GB] Sizeredolog = 1/2 x RAM
[systems > 512 GB] Sizeredolog = (min) 512 GB
Before you install the SAP HANA binary, configuration, trace, and log files, every SAP HANA node must have access to a file system that is mounted under the local /hana/shared/ mount point. 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 a Network File System (NFS) for this purpose. PowerStore unified storage systems can provide this file system with the NAS option. If there is a NAS or NFS option available to provide the /hana/shared mount point, PowerStore can be configured as block-only.
You can calculate the size of the /hana/shared/ file system by using the formula in the SAP HANA Storage Requirements white paper. This paper is included as an attachment in SAP Note 1900823: SAP HANA Storage Connector API. Version 2.10 of the white paper provides the following formulas.
Sizeinstallation(single-node) = 1 x RAM but max 1 TB
Sizeinstallation(scale-out) = 1 x RAM_of_worker per four worker nodes
SAP HANA supports backup to a file system or the use of third-party tools that SAP has certified. Dell Technologies supports data protection strategies for SAP HANA backup using Dell Data Domain systems and Dell NetWorker software. Although an SAP HANA backup to an NFS file system on a PowerStore all-flash or hybrid storage system is possible, backing up the SAP HANA database to the storage system where the primary persistence resides is not recommended. If you plan to back up SAP HANA to an NFS file system on a different Dell storage array, see the sizing information in the SAP HANA Storage Requirements white paper that is attached to SAP Note 1900823: SAP HANA Storage Connector API. The capacity depends on not only the data size and the frequency of change operations in the database, but also the number of backup generations that are kept on disk.