## 4.3.6  Develop Resilient Applications in the Kyma Runtime
All SAP BTP, Kyma runtime production plans ensure high availability. To benefit from the high-availability setup, make sure the architecture and deployment of your application comply with resiliency best practices. Use the following guidelines for Kubernetes and microservice-based applications to develop a stable application. Read further to find some Istio-related resiliency tips.
## Resilient Applications Deployed on Kubernetes
To develop resilient applications deployed on Kubernetes, use:
- Kubernetes built-in health checks. For more information, read how to Configure Liveness, Readiness and Startup Probes .
- Deployment across multiple availability zones for high availability. For more details, see the blog post .
- The Keda Module [page 1929] or Kubernetes autoscaling to automatically adjust the number of replicas based on resource usage.
- Rolling updates to minimize downtime during application updates. If you don't provide any configuration, rolling updates are by default enabled in your SAP BTP , Kyma runtime.
- BTP backing services, such as PostgreSQL or Object Store on SAP BTP. If you have to store some application data on SAP BTP, Kyma runtime, use persistent storage to ensure data is not lost in the event of a pod failure.
- Resource quotas to prevent resource starvation and ensure fair resource allocation.
- The Telemetry Module [page 1947] to configure a logging and monitoring solution to identify and troubleshoot issues in real time.
## Resilient Microservice-Based Applications
The Istio Module [page 1778] and Istio traffic management features help you achieve inbuilt microservices resiliency. Moreover, to develop resilient microservice-based applications, use:
- Istio's circuit breaker and retry features to prevent service overloads and recover from service failures.
- Distributed tracing with Istio's observability features to monitor the flow of requests across microservices and identify performance and error issues by shipping logs to SAP Cloud Logging (for details, see Integrate with SAP Cloud Logging [page 2011]).
- The Eventing module for asynchronous communication patterns, such as messaging queues, to decouple services and reduce dependencies. See how to Configure SAP Event Mesh for Kyma Eventing [page 2030].
- Health check endpoints as a part of your microservice. For more details, read Kubernetes API health endpoints .
- A centralized logging and monitoring solution to identify issues across multiple microservices and quickly troubleshoot them.
- A clear and well-defined boundary in your microservice`s design to minimize the impact of failures and enable easy replacement or scaling of individual services.
- Istio's service mesh to implement mutual TLS and authorization policies to secure communication between microservices. For more details, read the blog post .
- Network resiliency using Istio's traffic management features to test how your microservices respond to various failure scenarios, such as slow or failing services.
- The Telemetry Module [page 1947] to ship your Istio's access logs and metrics to your logging backend to monitor traffic patterns and quickly troubleshoot issues.
## Related Information
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