EMC DATA PROTECTION FOR SAP HANA

Transcription

1 White Paper EMC DATA PROTECTION FOR SAP HANA Persistence, Disaster Tolerance, Disaster Recovery, and Efficient Backup for a Data Center Ready SAP HANA EMC Solutions Group Abstract This white paper explains EMC s approach to data protection used with its SAP HANA Appliances. The SAP HANA Appliance protects data through: Persistence for booting and fallback in case of in-memory data failure High availability within the data center with EMC & Cisco UCS Disaster tolerance between data centers with EMC replication Backup and recovery with EMC Data Domain deduplication storage systems November 2013

2 Copyright 2013 EMC Corporation. All Rights Reserved. EMC believes the information in this publication is accurate as of its publication date. The information is subject to change without notice. The information in this publication is provided as is. EMC Corporation 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 EMC software described in this publication requires an applicable software license. For the most up-to-date listing of EMC product names, see EMC Corporation Trademarks on EMC.com. Part Number H12431a EMC Data Protection for SAP HANA 2

3 Table of contents Executive Summary... 4 Audience... 4 SAP HANA Appliances... 5 The SAP HANA Database... 5 SAP HANA Certification... 5 EMC s SAP HANA Appliance... 5 EMC s HANA Appliance Solution... 6 Availability... 6 Architecture... 6 Technologies... 7 Data Protection... 8 SAP HANA Persistence... 8 Data Volume... 9 Log Volume... 9 Restore from Persistence SAP Block API High Availability Node Failover Scenario Scale-Out Host with Auto-Failover Disaster Tolerance EMC MirrorView/S Scaling Disaster Tolerance Backup and Disaster Recovery Backup Solution Conclusion For More Information EMC Data Protection for SAP HANA 3

4 Executive summary To harness the potential of big data, SAP has targeted their SAP HANA in-memory database as their platform for innovation, and has recently announced support for SAP Business Suite on SAP HANA. The in-memory platform provides real-time analytics and transactions on a consolidated in-memory database that is optimized for both, avoiding the need to duplicate and restructure data for analytics. For those who can harness its power, real-time performance provides companies with extreme agility and a competitive advantage of being able to react instantly to important market changes. Regardless of the upside benefit, planning a move of a company s most missioncritical application to a new platform is no small undertaking. Ignoring the political ramifications, the technical team has to determine how to insure that the new platform will support its continuously available mission-critical applications. They also need to determine how they will protect their data and meet recovery time and recovery point objectives. Fortunately, all of these needs are addressed by EMC s data center ready SAP HANA solutions, available through Cisco or VCE. SAP HANA requires the use of an SAP-certified platform that simplifies the scaling of both storage and compute layers while providing enterprise-level business continuity with disaster tolerance. As partners, EMC and Cisco are raising the bar by bringing together the top SAP storage vendor with the most widely deployed base and the fastest-growing SAP infrastructure vendor to provide the optimum data center-ready solution with enterprise-class availability, disaster tolerance, backup, and recovery. EMC s data protection solution for the SAP HANA Appliance provides: Persistence for booting and fallback in case of in-memory data failure High availability within the data center with EMC and Cisco UCS Disaster tolerance between data centers with EMC replication Backup and recovery with EMC Data Domain deduplication storage systems Audience This white paper is intended for SAP Basis Administrators, storage administrators, IT architects, and technical managers responsible for designing, creating, and managing mission-critical SAP applications in 24/7 landscapes. It describes EMC s data protection solution for SAP HANA providing persistence, high availability, disaster tolerance, faster, more efficient SAP HANA database backup and recovery, plus complete control over the SAP HANA disaster recovery procedures. EMC Data Protection for SAP HANA 4

5 SAP HANA Appliances To harness the potential of big data, SAP has targeted their SAP HANA in-memory database as their platform for innovation. SAP has recently announced support for SAP Business Suite on SAP HANA and is quickly moving other applications. The inmemory platform provides real-time analytics and transactions on a consolidated inmemory database that is optimized for both. This avoids the need to duplicate and restructure data for analytics while providing real-time information for unprecedented corporate agility. The SAP HANA database The SAP HANA database is an in-memory database that combines transactional data processing, analytical data processing, and application logic processing functionality in memory. SAP HANA removes the limits of traditional database architecture that have severely constrained how business applications can be developed to support real-time business. SAP HANA s database design lets you perform real-time online analytical processing (OLAP) analysis on an online transaction processing (OLTP) data structure. As a result, you can address today s demand for real-time business insights by creating business applications that previously were neither feasible nor cost-effective. SAP HANA certification SAP HANA requires the use of an SAP-certified platform that simplifies the scaling of both storage and compute while providing enterprise level business continuity and disaster tolerance. To gain SAP HANA certification, SAP HANA solutions are fully tested by SAP. Today, HANA Solutions are delivered to customers as an appliance with factory pre-installed hardware, operating system, and SAP HANA database software, either as a single-node or multi-node cluster, on proven hardware provided by SAP s hardware partners. With the appliance model, the hardware components include dedicated servers using the latest Intel CPU architecture to run the SAP HANA database software as well as dedicated network and storage components. In the future, customers will be offered other deployment options, including configurations that can be built on their installed infrastructure. EMC s SAP HANA Appliance As partners, EMC and Cisco are raising the bar by bringing together the top SAP storage vendor with the most widely deployed base and the fastest growing SAP infrastructure vendor to provide the optimum data center-ready solution with enterprise class availability, disaster tolerance, backup, and recovery. By using popular technology solutions, customers can move to the new SAP HANA platform using familiar tools, minimizing the learning curve. EMC Data Protection for SAP HANA 5

6 EMC s HANA Appliance solution The SAP HANA Appliance by EMC and Cisco is a scale-out solution that enables IT departments to run big data, growth-oriented applications, and analytics by rapidly scaling to many nodes in high-performance, highly available configurations. The unified infrastructure inherent in the Cisco Unified Computing System (UCS) and EMC primary and protection storage for SAP HANA scale-out solution dramatically reduces the number of physical components required. It effectively uses limited space, power, and cooling by deploying less infrastructure to perform the same or even more work. For example, the unified fabric built into Cisco UCS results in fewer network interface cards (NICs), host bus adapters (HBAs), cables, and upstream switch ports, and eliminates the need for parallel Fibre Channel or management networks. Availability Architecture The SAP HANA Appliance by EMC and Cisco is available either directly through Cisco or through VCE. The VCE solution is very similar architecturally, based on Cisco UCS and Vblock and with the same inherent functionality. VCE adds attractive lifecycle management services such as preselecting and pretesting patches and upgrades. By combining EMC s expertise in storing, protecting, and managing vast amounts of data with the power and flexibility of Cisco UCS, Cisco, VCE, and EMC are reshaping the IT landscape. With 20,000 joint customers and 16 joint solution centers, Cisco, VCE, and EMC understand customer challenges, share a common vision, and have a deep technology alignment that enables them to help customers implement the right solution at the lowest total cost of ownership (TCO) through extensive collaboration, testing, and validation. The Cisco UCS with EMC primary and protection storage for SAP HANA scale-out solution combines the innovative Cisco UCS platform with EMC VNX Series unified storage and EMC Data Domain deduplication storage systems to deliver a highperformance, scalable infrastructure. 1 The SAP HANA in-memory database holds the bulk of its data in memory for maximum performance but still uses persistent storage to provide a fallback in case of a failure. The SAP HANA persistence volumes reside on the VNX array. Each node uses two LUNs, one for data and another for logs as shown in Figure 1. SAP HANA data is backed up to a Data Domain system over NFS. 1 The SAP HANA version considered as reference for concepts when writing this document was SAP HANA 1.0 SP6 EMC Data Protection for SAP HANA 6

7 Figure 1. Cisco EMC SAP HANA Appliance Cisco UCS B440 M2 servers are used as the compute nodes within the appliance. Each server becomes a single HANA node. The VNX array contains the server boot LUNs as well as the SAP HANA shared directories. Technologies EMC s data center ready SAP HANA solutions use a combination EMC, Cisco, and SAP technologies along with VCE service offerings. These technologies and offerings include: Table 1. Technologies of the EMC SAP HANA Appliance solution EMC Cisco SAP EMC VNX5300 EMC MirrorView EMC Data Domain EMC Unisphere UCS 5108 Chassis UCS B440 M2 Cisco UCS C200 M2 Cisco UCS 6248UP FI Cisco Nexus 5596UP Cisco Nexus 2244IP SAP HANA Database SAP HANA Studio SAP HANA Client For more information on these technologies, please visit the vendors respective websites. EMC Data Protection for SAP HANA 7

8 Data protection For EMC s SAP HANA Appliance solution to qualify for data center readiness, it requires data protection in depth, featuring various levels of protection as depicted in Figure 2. Figure 2. SAP HANA data protection layers As an SAP HANA data-center-ready solution, the SAP HANA Appliance by EMC and Cisco protects data through: Persistence: Persistence for booting and fallback in case of in-memory data failure High availability (HA): Redundant components, manageability (IIPA), and node failover make the server reliable within the data center Disaster tolerance (DT): Protects from complete server failure within and between data centers with EMC replication and EMC Data Domain systems Backup and disaster recovery (DR): Protects from complete data center disaster using backup and disaster recovery with EMC Data Domain systems and remote fail-over SAP HANA persistence The SAP HANA in-memory database holds the bulk of its data in memory for maximum performance but still uses persistent storage to provide for booting and fallback in case of a failure. Persistence is managed by the SAP Block API to ensure exclusive access to persistence. The SAP HANA persistence resides on either internal disks (single node) or on shared storage (multi-node cluster) and uses two volumes: Data and Log, as shown in Figure 3. EMC Data Protection for SAP HANA 8

9 Figure 3. The SAP HANA persistence layer Data and undo log information are automatically saved to disk at regular savepoints as depicted in Figure 4and described in the following sections. Figure 4. Persistence Mechanism Data Volume Data in memory is asynchronously written to the persistence mechanism as a savepoint every five minutes by default. This data volume also contains undo log information and additional HANA information such as modeling data. The data volume savepoint capture method uses a locking mechanism to prevent modification of pages while copying modified pages and capturing open transactions before finally increasing the savepoint version and releasing the lock. Log Volume The log file system captures all database transactions since the last savepoint. It is saved to disk continuously and synchronously after each commit of a database transaction at the end of the disk write operation, or if the internal log buffer (1MB) is full. As always, this information allows the database to be rolled back to any point in time as well as to back out of or redo individual transactions. In case of failure, the log volume allows the database to be restored from the last savepoint onwards. EMC Data Protection for SAP HANA 9

10 Restore from Persistence After a power failure, the database can be restarted like a disk-based database: Lazy Reload: System is normally restarted with lazy reloading of tables to keep the restart time short. This means that tables with a preload flag and subsequently requested tables are loaded first. Replay Logs: System returns to its last consistent state by replaying the redo log since the last savepoint. SAP Block API Persistence is controlled by the HANA name server using the SAP Block API. This ensures exclusive access to persistence using SCSI-3 PGR (persistent group reservations). This ensures that only the owning node has access to the persistence layer as well as has persistence mounted. The SAP Block API was co-developed by SAP and EMC. High Availability EMC worked with SAP to develop the concept of a scale-out appliance for scalability and high availability. High availability within the data center provides protection from both storage and server failures. To ensure high availability, Cisco and EMC provide a redundant configuration that eliminates single points of failure with host autofailover. 4-Node Failover Scenario Figure 5 shows a typical 4-node configuration where there are three HANA worker nodes and one extra node configured as a HANA standby node. The standby node is configured as a warm standby to provide a non-disruptive recovery from node failures. Figure 5. HANA HA example with three worker nodes plus standby. EMC employs SAP s Block API for non-disruptive failover when a node fails. The whole process is controlled by the SAP HANA name server, which also triggers the calls to the Block API. As shown in Figure 6, during a node failure, the standby node assumes its workload. When the node is restored, it becomes the new standby. EMC Data Protection for SAP HANA 10

11 Figure 6. Non-disruptive failover to standby node Scale-Out Host with Auto-Failover Extracting deep insight from stored information within limited time frames becomes harder as data volumes grow. SAP HANA delivers scale-out solutions that enable IT departments to run big data, growth-oriented applications and analytics by rapidly scaling to many nodes in high-performance, highly available configurations. This scale out solution allows businesses to easily add additional nodes as needed while insuring system and data high availability with auto-failover. HANA host auto-failover functionality protects against server hardware failures. HANA permanently monitors the status of all processes. If a failure of one server node is detected, HANA automatically shuts down this server and moves the respective data to one of the configured standby nodes. The standby node reads the data of the failing node from the shared storage infrastructure and fully takes over the role of this node. There is no loss of data or committed transactions. Disaster Tolerance Disaster tolerance provides complete protection in the event of a storage system failure or in the event of a failure of the entire production site. This section describes the basic concepts of EMC s certified SAP HANA disaster tolerance implementation based on Cisco UCS servers and EMC VNX Series storage arrays. The SAP HANA DT solution uses the storage-based replication, EMC MirrorView /Synchronous (MirrorView/S). EMC MirrorView/S EMC MirrorView/S provides the key functionality for EMC s SAP HANA Data Protection solution supporting high availability and disaster tolerance, for VNX series arrays. It is a limited-distance synchronous data mirroring facility that maintains a synchronized remote mirror of production on the destination VNX system at a separate location. MirrorView/S provides SAP HANA with: Continuous Replication: MirrorView/S provides end-to-end data protection by replicating the contents of a primary volume to a secondary volume that resides on a different VNX series or CLARiiON series storage system. Data Protection: MirrorView data protection is defined as end-to-end because, in addition to performing replication, it protects the secondary volume from EMC Data Protection for SAP HANA 11

12 tampering or corruption by only making the volume available for server access when initiated through MirrorView. Consistency Groups: A unique consistency technology for the midrange market that replicates write-order dependent volumes. Using this technology, MirrorView maintains write ordering across secondary volumes in the event of an interruption of service to one, some, or all of the write-order dependent volumes. Scaling Disaster Tolerance The SAP HANA Appliance by EMC and Cisco provides the flexibility to scale disaster tolerance capabilities to meet the needs of each company. There are three available options for failover, each bringing an increasing amount of data security. System Replication Providing active/active disaster tolerance, system replication is implemented inside SAP HANA. During a failure of either system, the synchronous mode ensures that there is no data loss and production is maintained with the other active system. The key advantage to system replication is that fail-over only takes about five minutes. System replication is shown in Figure 7. Figure 7. DT with system replication Storage Replication In an SAP-certified active/passive configuration through storage replication, MirrorView/S provides a complete disaster tolerance configuration of the SAP HANA database by writing data to two VNX systems in separate locations, using mirrors of source LUNs and their equivalent destination LUNs. Synchronous replication ensures that the second copy of the data associated with the source LUNs is accurate to the last transaction and is available for use at the destination site after a MirrorView/S failover procedure. This backup system can be used for QAS/DEV or non-critical production. Although failover is longer than with system replication at around an hour, it costs less to implement and it supports remote failover for added geographic protection. Storage replication is illustrated in Figure 8. EMC Data Protection for SAP HANA 12

13 Figure 8. DT with storage replication In an active/passive MirrorView/S configuration: 1. Data is written to the source VNX system 2. MirrorView/S copies the data to the destination VNX 3. The remote VNX performs a cyclic redundant check (CRC) on the data in cache and sends an acknowledge to the source VNX 4. The write-acknowledge signal is sent to the SAP HANA node that initiated the I/O request In the event of a disaster or unavailability of Site A, the SAP HANA database needs to failover to Site B. This is a manual process and includes the following steps: 1. Storage failover of the file components to the target array at Site B 2. Storage failover of the HANA node persistence LUNs to Site B 3. Update the SAP HANA Storage Connector API global.ini file 4. Associate the corresponding UCS service profiles to the UCS blades at the destination site (if required) 5. Boot the UCS blades from the target array at Site B 6. Start the SAP HANA database at Site B System plus Storage Replication By combining the two previous solutions, you get the benefit of both. This option provides for the high possible availability within and between data centers, and is shown in Figure 9. EMC Data Protection for SAP HANA 13

14 Figure 9. DT with system plus storage replication Backup and Disaster Recovery The SAP HANA Appliance has many lines of defense for data protection which have been described in this paper. However, in extreme cases where a disaster occurs that can t be solved with local persistence and HA methods, it is always a recommended practice to have a defined backup and disaster recovery strategy. For SAP HANA, the final line of defense is a backup which is required in the unlikely event that HANA is unable to start from a consistent point-in-time after a failure. Backup solution The SAP HANA Appliance backup solution consists of backups orchestrated through SAP HANA Studio to the Data Domain system via NFS as seen in the following figure. Figure 10. SAP HANA backup over NFS to a Data Domain system Backups can be triggered using the SAP HANA Studio, the DBA Cockpit in Business Warehouse (BW), SQL script commands or third party tools. Configuration files can be backed up by using a simple script that is executed by cron under Linux. Since these are not automatically run by the SAP HANA system, each HANA database administrator will have to design a backup strategy with the hardware vendor before purchasing SAP HANA to ensure that they have the appropriate hardware to support the backup process. EMC Data Protection for SAP HANA 14

15 Data Domain EMC Data Domain deduplication storage systems deliver industry-leading performance and scale for the protection of HANA databases. They offer a costeffective alternative to tape and provide faster, more reliable recovery and longer retention on disk. Data Domain inline deduplication dramatically reduces the amount of disk storage needed to retain and protect enterprise data. With the industry s fastest deduplication storage controller, Data Domain systems allow more backups to complete faster while putting less pressure on limited backup windows. All Data Domain systems are built as the storage of last resort. The data in each Data Domain system is protected by the EMC Data Domain Data Invulnerability Architecture an end-to-end data verification, continuous fault detection and selfhealing mechanisms coupled with other resiliency features transparent to the application. This ensures reliable recovery of SAP HANA data every time. Data Domain systems also integrate easily into your existing environment, enabling you to consolidate all backup and archive data on a single protection storage system. For example, you can use the same Data Domain system to protect SAP HANA, Microsoft Exchange, and VMware backup data as well as database archives. Data Domain is the ideal solution to protect SAP HANA because it provides: Performance and Scale: With inline deduplication to reduce storage requirements and a throughput of up to 31 TB per hour, it provides the speed and scalability needed to handle big data. Reliable Recovery: The Data Invulnerability Architecture provides end-to-end data verification, continuous fault detection, self-healing, and additional resiliency features to ensure recovery in any circumstance. Network-Efficient Replication: Data Domain replicator software sends only unique, compressed data across existing networks, providing faster time-to-dr readiness. Seamless Integration: Qualified for all SAP HANA configurations and optimized for SAP HANA Studio over NFS. Restore from Backup The recovery of SAP HANA Database is performed through SAP HANA Studio. SAP HANA supports the following recovery types: 1. Recover the database to its most recent state, 2. Recover the database to a point-in-time 3. Recover the database to a specific data backup For solutions one and two, both data backup and redo log backup will be used. For solution three, only data backup will be used. EMC Data Protection for SAP HANA 15

16 Conclusion Although SAP HANA s in-memory design adds additional considerations to a typical data protection model, EMC s data protection solution - developed jointly with Cisco and SAP - allows customers to be confident that their data is completely protected. In addition, EMC s SAP HANA Appliance data protection solution takes advantage of an already familiar EMC toolset that minimizes the learning curve for EMC customers. By defining and integrating the data protection solution into an appliance, the implementation of the entire HANA solution including data protection is greatly streamlined. The key addition to a typical data protection model is the need for persistence to back up the in-memory database in case of power failure or data corruption. The persistence allows for the database to be restarted like a disk-based database after a power failure or other failure. This persistence is the key to all the other layers of protection from backup to remote replication that both pull from these persistence volumes. Data Domain provides a reliable and efficient means to perform normal backups and restoration of system files. In the event of a disaster, a current copy of the data, logs, and even configuration files can be easily restored from a local or remote Data Domain system. The Data Invulnerability Architecture ensures that the data can always be restored. Disaster tolerance for the Cisco EMC SAP HANA Appliance enables a remote system to assume the workload of a production HANA Database in the event of a catastrophic failure, without losing committed changes to the database. Within this SAP-certified solution, local and remote consistency pairs ensure all storage devices are synchronized as changes are made to the production system. Service Profiles enable the use of the compute and network resources on the remote site for QA & Dev under normal operating conditions. In the event of a planned or unplanned outage on the primary site the Service Profile can be quickly changed to that of the production system. EMC Data Protection for SAP HANA 16

17 For More Information The EMC Cisco SAP HANA Appliance data protection solution is part of the EMC Solution Suite for SAP. To learn more about this and other SAP solutions, visit or contact your local EMC, VCE, or Cisco representative. Additional information can be found at: White Paper: EMC Disaster Tolerance for SAP HANA White Paper: EMC Data Domain Deduplication Storage Systems -SAP HANA Data Protection EMC Data Protection for SAP HANA 17