What is ClusterLion for SAP?
SAP Hana environments demand the highest degree of availability – in most cases it is critical. ClusterLion for SAP was developed to implement automatic switchover and offers the highest degree of availability and ensures data consistency at all time.
With ClusterLion, there is no need to operate a third site or the connection lines associated with that – this task is performed by ClusterLion with the provision of a Cloud Quorum service. For customers who are reluctant to employ cloud services, there is an on-premise solution available.
Once ClusterLion is implemented, you only require Linux Single Server systems without cluster services, which greatly reduces the complexity of your infrastructure. With ClusterLion all services remain online, even if one of your sites is affected by a total outage.
Cisco Intersight explained:
Cisco Intersight is a software-as-a-service (SaaS) infrastructure lifecycle management platform that delivers simplified configuration, deployment, maintenance, and support. It supports Cisco Unified Computing System (Cisco UCS) and Cisco HyperFlex hyperconverged infrastructure, other Cisco Intersight-connected devices, and third-party Intersight-connected devices. The level of functionality may vary.
The majority of our users enjoy the benefits of SaaS; however, if you have data locality or security needs for managing systems that may not fully meet a SaaS management model, you can leverage the Cisco Intersight Virtual Appliance software on-premises to connect your servers through Intersight.com.
With Intersight, you get all of the benefits of SaaS delivery and full lifecycle management of distributed Intersight-connected servers and third-party storage across data centers, remote sites, branch offices, and edge environments. This empowers you to analyze, update, fix, and automate your environment in ways that were not possible with prior generations’ tools. As a result, your organization can achieve significant TCO savings and deliver applications faster in support of new business initiatives.
Why ClusterLion with Intersight integration offers a perfect solution for SAP High Availability:
In the high availability context, two points always require careful consideration but often represent a major challenge: 1) the integrity of data and 2) the availability of services.
To maintain integrity and availability, cluster services and fencing mechanisms are usually employed. The purpose of fencing is to ensure the functionality and integrity of the cluster by removing individual resources or nodes.
However, this is where the resulting complexity can lead to a loss of overview and things can go wrong very quickly. Too often the opposite is achieved and instead of increasing availability, it is reduced.
ClusterLion reduces the complexity, as conventional clustering is not necessary. The SAP hosts are not touched and remain exactly as they are. As an independent service, ClusterLion monitors everything externally. The setup is easy and the direct integration into Cisco Intersight also ensures a simple and clear fencing mechanism.
Before we look at configuring ClusterLion for use with Intersight, it is important to note the following assumptions: a) the basic setup for ClusterLion has already been done, and b) Intersight has already been set up (this set up is beyond the scope of this article).
How to configure ClusterLion for use with Intersight:
You simply create an API key in Intersight according to OpenAPI schema version 3.
For ClusterLion just open the configuration portal and choose “Environment Integrations”. Here you will find all currently available options for a possible power-off by ClusterLion, or what many people probably know as “fencing devices”. Add a new connection, paste your API token and upload the secret key. Verify that it is working – and you are done – The ClusterLion is now connected to Intersight.
How to add an SAP HANA system to ClusterLion:
If all users and authorizations for the ClusterLion have already been prepared, simply use the easy “Setup new HANA System” wizard and the system is configured in a few minutes. The instance can then be managed via the Config portal and the current status of the database is now visible in the status portal.
What happens if the HANA database fails?
The ClusterLion immediately recognizes that something is wrong with the HANA and shows this in the status portal. A correlation machine, the so-called rule engine, is running in the background and checks in real time whether there is a need for any action to keep the database available.
If the ClusterLion determines that the primary side is no longer working properly and the System Replication is in sync, the ClusterLion initiates the shutdown via Intersight and, if this was successful, switches the database on the other side to primary mode and takes over the Service IP.
ClusterLion Takeover procedure:
ClusterLion offers a superior alternative to conventional cluster systems and brings an additional level of availability due to the simplicity and reduction in complexity.
Thanks to the integration in Intersight, ClusterLion is a particularly attractive solution for SAP HANA operators who already use Cisco Intersight or who have many Cisco UCS in use and are considering purchasing Intersight.