Service Mesh (Beta)
This topic describes service mesh for Pivotal Application Service.
To deploy service mesh, see Deploying Service Mesh (Beta).
PAS includes an optional, beta routing plane that uses a service mesh. A service mesh provides traffic management, security, and observability for microservices. For more information, see What is a service mesh? in the Istio documentation.
Service mesh in PAS uses Istio Pilot and Envoy. The Cloud Foundry
istio-release packages these components into a BOSH release. For more information, see the following:
- The Pilot section in Istio documentation.
- The What is Envoy topic in the Envoy documentation.
- The istio-release repository in GitHub.
Service mesh deploys an additional router and runs as a parallel routing plane as illustrated in the following diagram:
Service mesh currently supports configuring routing weights for app. For more information, see Using Weighted Routing (Beta).
Consider the following when deploying service mesh:
- It does not have feature parity with the existing routing plane in PAS.
- It is for deployments with fewer than 20,000 routes. At greater scale, it may impact core platform functions.
- The control plane is not HA and registration of new routes may be delayed during upgrade.
- The domain for routes is
*.mesh.YOUR-APPS-DOMAINand is not configurable.
The following table describes each component VM deployed as part of service mesh in PAS, along with their function.
|istio-router||envoy||A reverse proxy to forward HTTP/HTTPS requests external to the platform to applications on the platform.|
|istio-control||copilot, pilot-discovery||Propagates PAS external routes to all service mesh routers.|
|route-syncer||cc-route-syncer||Syncs routes created through the Cloud Controller API to the service mesh control plane.|
For information about the communication ports and protocols used by these components, see Service Mesh in the Routing Network Communications topic.