One of the key things customers look for when deploying SAP workloads on AWS is having high availability (HA) set up for their business/mission-critical SAP applications. In this blog post, we discuss the HA option for customers running their SAP workloads on Red Hat Enterprise Linux (RHEL). Red Hat provides SAP certified high availability solutions for various SAP components. Red Hat has extended HA add-on components, including pacemaker, STONITH, corosync, and resource agents. Customers can build HA clusters across AWS Availability Zones within a Region for SAP HANA and SAP NetWeaver-based applications.

AWS provides a broad variety of Amazon EC2 instances certified by SAP for SAP HANA and SAP NetWeaver-based applications. For SAP HANA, there are SAP-certified Amazon EC2 instances ranging from 244 GiB to 24 TiB of memory. For NetWeaver-based applications, there are more than 50 SAP supported Amazon EC2 instance types to choose from. For complete details, see the Certified and Supported SAP HANA Hardware Directory and SAP OSS Note 1656099 (login required). You can configure this high availability add-on from Red Hat for SAP HANA databases and SAP Central services (ASCS/SCS) on any SAP certified and supported Amazon EC2 instances.

Figure 1: SAP ASCS and HANA set up as HA using RHEL cluster

The preceding figure is the architecture representation of the SAP ABAP System Central Services (ASCS) and HANA HA setup. The ASCS, Primary HANA node, and primary application server (PAS) are deployed in Availability Zone A (us-east-1a). The Enqueue Replication Server (ERS), standby HANA database, and additional application server (AAS) are deployed in Availability Zone B (us-east-1b). There are two sets of RHEL clusters. The first is for the SAP application, and this is the setup between the ASCS and ERS instances. The second is for the HANA setup between the primary and standby HANA database (DB). The Route53 service here is used as a DNS service. This allows you to create a CNAME for the FQDN with your company domain name and NLB DNS name. You can also leverage your on-premises DNS service for the same.

The details on how to set up the cluster are described in the upcoming sections. This starts with getting the right subscription that provides the required agents for the HA configuration.

Getting the right RHEL subscription

The RHEL high availability add-on is only available as part of Red Hat Enterprise Linux for SAP Solutions. Customers have two subscription options:

•  AWS Marketplace – Customers can choose to purchase subscriptions for RHEL for SAP with HA and US from the AWS Marketplace. This is available with either an on-demand or yearly subscription model. It is available across all AWS commercial and AWS GovCloud (US) Regions. Additionally, AWS Marketplace Amazon Machine Image (AMIs) are supported by AWS Premium Support.
• Bring your own subscription (BYOS) – Red Hat provides an additional option to port existing or newly purchased AWS subscriptions with the Red Hat Cloud Access Program. This may be a desirable option for those who have already purchased a subscription from Red Hat and are migrating existing SAP workloads to AWS.

To get more details and a deeper understanding of which option is best for your organization, refer to the Red Hat Enterprise Linux for SAP offering on Amazon Web Services FAQ.

Manual deployment

AWS and Red Hat extended the HA solution to AWS and documented the configuration guides to help with deployments. Refer to the RHEL HA for SAP HANA and RHEL HA for SAP NetWeaver from Red Hat for details.

Figure 2: Manual Deployment Process for HA setup of SAP ASCS and HANA using RHEL cluster

The preceding figure is the flow of the Manual Deployment process for HA setup of SAP ASCS and HANA using RHEL Cluster. You start with reviewing the guides from SAP and RHEL and get the RHEL subscription either from Amazon Market Place or BYOS. After this you launch the EC2 instances in the chosen AZ’s and configure the required storage. This is followed by completing the OS specific configuration and then finally the installation of SAP HANA and NetWeaver. Post this you can refer to the SAP NetWeaver and HANA Guide to configure the HA cluster.

AWS Quick Start for SAP HANA

To help you get started quickly and assist you with your HA deployment for SAP HANA, we enhanced our SAP HANA on AWS Quick Start. This supports Multi-AZ single-node deployments with the RHEL for SAP with HA and US product from the AWS Marketplace. The Quick Start supports the performance-optimized setup for SAP HANA. It provisions both a primary and a standby HANA server, which have the same instance size and other infrastructure characteristics. They are deployed in separate private subnets in two difference Availability Zones and are configured for synchronous HANA system replication (HSR) and HA. You can choose to create a new virtual private cloud (VPC) for your deployment, or provision the SAP HANA servers in your existing VPC infrastructure. The deployment takes less than 2 hours. Read through the deployment guide to get more details.

Conclusion

We hope you will benefit from this information about using RHEL as an operating system for deploying highly available SAP workloads on AWS. While we can set up the HA cluster in an automated way using the SAP HANA on AWS Quick Start, the configuration guide provides a deeper insight on the setup. To learn more about using Red Hat’s High Availability solutions for SAP workloads on AWS, check out the recorded webinar “Build a solid landscape for SAP HANA and S/4HANA on AWS” from AWS and Red Hat.

Let us know if you have any comments or questions—we value your feedback.