Chapter 2. Preparing the SAP HANA Scale-Out environment For a complete SAP HANA Scale-Out environment with System Replication and Pacemaker integration, it is advisable to gather all necessary data in advance and to prepare the infrastructure for the installation process. The installation of SAP HANA requires a large number of variables from different operating system components, including SAP itself. The minimum requirements are described in this chapter. 2.1. Subscriptions and repositories Requirements for SAP HANA deployment: RHEL for SAP Solutions Subscriptions must be enabled on all RHEL servers running SAP HANA. Staging environment with satellite server to ensure the correct package versions are installed on every system.The following repository must be enabled for installing SAP HANA on RHEL 8: rhel-8-SAP-Solutions : rhel-8-for-<arch>-sap-solutions-rpms (RHEL 8.10) rhel-8-for-<arch>-sap-solutions-e4s-rpms (RHEL 8.0 to 8.8) The <arch> denotes the specific hardware architecture as follows: x86_64 ppc64le For more information, see Overview of Red Hat Enterprise Linux for SAP Solutions Subscription and RHEL for SAP Subscriptions and Repositories . A separate storage network, backup network, and admin network are not required for this solution. In addition to the network configuration, use Pacemaker to configure an additional virtual IP. This IP address allows SAP application servers and certain end-users to communicate with the SAP HANA environment. The following example lists the minimum requirements for a network configuration of eight SAP HANA nodes. Parameter Value domainname example.com NTP Server 1 0.de.pool.ntp.org NTP Server 2 1.de.pool.ntp.org Virtual IP 10.111.222.52/24 Note Note: Pacemaker manages the virtual IP (VIP) address in the public network for communication between the SAP application server and the SAP HANA database. The following example lists the physical addresses that are mapped to hosts with three NICs (Network Interface Cards). Table 2.1. Datacenter 1 Hostname Public Network HANA Communication Pacemaker dc1hana01 10.0.1.21/24 192.168.101.101/24 192.168.102.101/24 dc1hana02 10.0.1.22/24 192.168.101.102/24 192.168.102.102/24 dc1hana03 10.0.1.23/24 192.168.101.103/24 192.168.102.103/24 dc1hana04 10.0.1.24/24 192.168.101.104/24 192.168.102.104/24 Table 2.2. Datacenter 2 Hostname Public Network HANA Communication Pacemaker dc2hana01 10.0.1.31/24 192.168.101.201/24 192.168.102.201/24 dc2hana02 10.0.1.32/24 192.168.101.202/24 192.168.102.202/24 dc2hana03 10.0.1.33/24 192.168.101.203/24 192.168.102.203/24 dc2hana04 10.0.1.34/24 192.168.101.204/24 192.168.102.204/24 Hostname Public Network Pacemaker majoritymaker 10.0.1.41/24 192.168.102.100/24 2.2. Storage There are two methods to configure storage for an SAP HANA Scale-Out scenario: Shared storage Non-shared storage There is no communication between both scale-out environments on the storage level. As a result, storage configuration must be completed on each scale-out environment to ensure SAP HANA System Replication is working as expected. 2.2.1. Shared storage Shared storage configuration requires methods and mount points. When configuring shared storage over NFS, the NFS Server, NFS Paths, and directories are necessary, and it is necessary to provide the directories /hana/data , /hana/log , and /hana/shared . Table 2.3. Datacenter 1 Method NFS Server NFS Path Mount Point NFS 10.0.1.61/24 /data/dc1/data /hana/data NFS 10.0.1.61/24 /data/dc1/log /hana/log NFS 10.0.1.61/24 /data/dc1/shared /hana/shared Table 2.4. Datacenter 2 Method NFS Server NFS Path Mount Point NFS 10.0.1.61/24 /data/dc2/data /hana/data NFS 10.0.1.61/24 /data/dc2/log /hana/log NFS 10.0.1.61/24 /data/dc2/shared /hana/shared 2.2.2. Non-shared storage Non-shared storage configuration requires the integration of the storage connector. The storage connector manages access to the LUNs or LVM Devices over SCSI or LVM locking mechanisms. For this configuration type, WWID or LVM devices are needed. For a non-shared storage configuration, one shared directory is required for each scale-out environment. This configuration is described in the SAP HANA Fiber Channel Storage Connector Admin Guide . Table 2.5. Non-shared storage example Parameter Value ha_provider hdb_ha.fcClient Table 2.6. Datacenter 1 Method Parameter Name WWID SAN partition_1_data wwid 3600508b400105e210000900000491000 SAN partition_1_log wwid 3600508b400105e210000900000492000 SAN partition_2_data wwid 3600508b400105e210000900000493000 SAN partition_2_log wwid 3600508b400105e210000900000494000 SAN partition_3_data wwid 3600508b400105e210000900000495000 SAN partition_3_log wwid 3600508b400105e210000900000496000 Table 2.7. Datacenter 2 Method Parameter Name WWID SAN partition_1_data wwid 3600508b400105e210000900000491000 SAN partition_1_log wwid 3600508b400105e210000900000492000 SAN partition_2_data wwid 3600508b400105e210000900000493000 SAN partition_2_log wwid 3600508b400105e210000900000494000 SAN partition_3_data wwid 3600508b400105e210000900000495000 SAN partition_3_log wwid 3600508b400105e210000900000496000 2.2.3. Shared devices Table 2.8. Datacenter 1 Method NFS Server NFS Path Mount Point NFS 10.0.1.61 /data/dc1/shared /hana/shared Table 2.9. Datacenter 2 Method NFS Server NFS Path Mount Point NFS 10.0.1.61 /data/dc2/shared /hana/shared Note If the shared storage is managed by a filesystem resource, the mount should not be added into the /etc/fstab . 2.3. SAP HANA There are four steps in building an SAP HANA deployment for a scale-out environment with SAP HANA System Replication: Configuring the operating system. Installing the SAP Host Agent. Deploying two scale-out environments. Activating HANA System Replication after both SAP HANA Scale-Out environments are running. Preparation of the RHEL environment includes provisioning the SAP HANA installation sources. Installation sources are available from SAP. You must have an SAP account to download the installation sources, which are provided over a shared directory, or copied manually on every host. SAP software can be downloaded from the SAP Software Center . In our example, we put the software in a shared directory /install. Table 2.10. Installation sources for SAP HANA Host Agent Software Path Host Agent /install/51053381/DATA_UNITS/HDB_SERVER_LINUX_X86_64/server/HOSTAGEN T.TGZ SAP HANA /install/51053381/DATA_UNITS/HDB_SERVER_LINUX_X86_64/ The following information is required for the deployment of the SAP HANA Host Agent: Parameter Value sapadm user password Us3Your0wnS3cur3Password Hostagent SSL certificate password Us3Your0wnS3cur3Password sapadm User ID 996 For an SAP HANA deployment, the following additional parameters are required: Parameter Value shmadm group ID 20201 sapsys group ID 996 SID RH1 System number 10 <sid>adm password Us3Your0wnS3cur3Password HANA components client,server System type Master System usage custom System User Password (SAP) Us3Your0wnS3cur3Password Table 2.11. SAP HANA deployment datacenter 1 hdblcm Parameter Value hostname dc1hana01 Addhosts parameter dc1hana02:role=worker,dc1hana03:role=worke r,dc1hana04:role=standby ScaleOut Network DC1 internal_network 192.168.101.0/24 Table 2.12. SAP HANA deployment datacenter 2 hdblcm Parameter Value hostname dc2hana01 Addhosts parameter dc2hana02:role=worker,dc2hana03:role=worke r,dc2hana04:role=standby ScaleOut Network DC2 internal_network 192.168.101.0/24 Table 2.13. HSR configuration Parameter Value Operation mode logrelay Replication mode sync Backup directory /hana/shared/L01/HDB10/backup/ Table 2.14. Datacenter 1 Parameter Value System replication name DC1 HSR type PRIMARY HSR remote host dc1hana01 SR network 192.168.101.0/24 Table 2.15. Datacenter 2 Parameter Value System replication name DC2 HSR type Secondary HSR remote host dc2hana01 SR network 192.168.101.0/24 2.4. Pacemaker Pacemaker manages the configuration of SAP HANA Scale-Out System Replication. For a working configuration, Pacemaker requires a fencing method. This can be achieved by the STONITH Pacemaker configuration. For an overview of STONITH methods, refer to Support Policies for RHEL High Availability Clusters-Fencing/STONITH . There are many fence-agents available, please also check: yum search fence-agents Pacemaker fencing configuration is dependent on the underlying hardware or the virtualization environment. In this solution, because Red Hat Virtualization (RHV) is used, the fence_rhevm fencing method must be configured according to the environment. To prevent split-brain scenarios a quorum is required. which is realized using an additional cluster node majoritymaker . If you need more information about quorum, please check Design Guidance for RHEL High Availability Clusters - Considerations with qdevice Quorum Arbitration and Exploring Concepts of RHEL High Availability Clusters-Quorum . Table 2.16. Majoritymaker parameters Hostname Public Network Pacemaker Majoritymaker 10.0.1.42/24 192.168.101.100/24 Table 2.17. General parameters Parameter Value Cluster name hana-scaleout-sr Fencing method fence_rhevm Fencing ipaddr/hostname 10.20.30.40 Fencing parameter fencing_user/password Corosync network 192.168.101.0/24 Password hacluster user Us3Your0wnS3cur3Password In this example, we use fence_rhevm . For more details about configuring fence_rhevm , please check How do I configure a fence_rhevm stonith device in a Red Hat High Availability cluster? .

Commands:
search fence-agents