Hello Colleagues !
In this blog, we shall look into how an SAP HANA Cloud Integration landscape meets the expectations of a cloud-based application. We shall look into the failover and scalability component of HCI-PI. This blog is part of the architectural overview of SAP HANA Cloud Integration. You can find all the blogs over here.
I refer to the node architecture of HANA Cloud Integration in this blog. So, it you are new to the concept, I strongly recommend you read this blog before reading further.
Fail-over Capability of HANA Cloud Integration
If the primary instance of a worker node fails to process messages, the failover capability kicks in. Unexpected single instance losses can be due to hardware, system or load failure. HANA Cloud Integration has been designed to be robust against these failures.
SAP HANA Cloud Integration can detect failures, gracefully handle failures, bring up new instances and redirect traffic from a downed instance to a live instance.The tenant management node supervises the worker nodes and shall immediately know if a worker node is not functioning. Health-check reports of worker nodes causes the tenant management nodes to take action.
A pictorial representation can help understand the failover capability of HCI.
Scalability of HANA Cloud Integration
Assume that you are running an Integration worker node and you are starting to get a high enough level of traffic and load. You can add additional integration worker nodes and configure to handle the load. The BigIP load balancer shall spread the load between all the instances. In this situation, you would serve the same integration artifacts from each of the instances - this is ensured by the tenant management node.
There are two levels of scalability for a worker node.
- Increase the VM size of the worker node
- Increase the number of worker nodes
SAP HANA Cloud Platform currently provides the following Virrtual Machine configurations
- Lite = 1 Core / 2GB RAM
- Professional = 2 Cores / 4GB RAM
- Premium = 4 Cores / 8 GB RAM
- Premium Plus = 8 Cores / 16 GB RAM, available in "à la carte" configurations
However, to increase the number of messages that can be handled per second, you have to increase the number of worker nodes. An increase in the number of worker nodes causes an almost linear increase in the number of messages that can be processed.
Note: By default, standard edition of SAP HANA Cloud Integration provides a VM Lite version and one instance of the worker node. You can opt for an higher version of the VM and for more VMs.
Best Regards,
Sujit