166a8b2a58
Co-authored-by: Matt Keeler <mkeeler@users.noreply.github.com> Currently when passing hostname clusters to Envoy, we set each service instance registered with Consul as an LbEndpoint for the cluster. However, Envoy can only handle one per cluster: [2020-06-04 18:32:34.094][1][warning][config] [source/common/config/grpc_subscription_impl.cc:87] gRPC config for type.googleapis.com/envoy.api.v2.Cluster rejected: Error adding/updating cluster(s) dc2.internal.ddd90499-9b47-91c5-4616-c0cbf0fc358a.consul: LOGICAL_DNS clusters must have a single locality_lb_endpoint and a single lb_endpoint, server.dc2.consul: LOGICAL_DNS clusters must have a single locality_lb_endpoint and a single lb_endpoint Envoy is currently handling this gracefully by only picking one of the endpoints. However, we should avoid passing multiple to avoid these warning logs. This PR: * Ensures we only pass one endpoint, which is tied to one service instance. * We prefer sending an endpoint which is marked as Healthy by Consul. * If no endpoints are healthy we emit a warning and skip the cluster. * If multiple unique hostnames are spread across service instances we emit a warning and let the user know which will be resolved.
Consul 
- Website: https://www.consul.io
- Tutorials: https://learn.hashicorp.com
- Forum: Discuss
Consul is a tool for service discovery and configuration. Consul is distributed, highly available, and extremely scalable.
Consul provides several key features:
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Service Discovery - Consul makes it simple for services to register themselves and to discover other services via a DNS or HTTP interface. External services such as SaaS providers can be registered as well.
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Health Checking - Health Checking enables Consul to quickly alert operators about any issues in a cluster. The integration with service discovery prevents routing traffic to unhealthy hosts and enables service level circuit breakers.
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Service Segmentation/Service Mesh - Consul Connect enables secure service-to-service communication with automatic TLS encryption and identity-based authorization. Applications can use sidecar proxies in a service mesh configuration to establish TLS connections for inbound and outbound connections without being aware of Connect at all.
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Key/Value Storage - A flexible key/value store enables storing dynamic configuration, feature flagging, coordination, leader election and more. The simple HTTP API makes it easy to use anywhere.
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Multi-Datacenter - Consul is built to be datacenter aware, and can support any number of regions without complex configuration.
Consul runs on Linux, Mac OS X, FreeBSD, Solaris, and Windows. A commercial version called Consul Enterprise is also available.
Please note: We take Consul's security and our users' trust very seriously. If you believe you have found a security issue in Consul, please responsibly disclose by contacting us at security@hashicorp.com.
Quick Start
A few quick start guides are available on the Consul website:
- Standalone binary install: https://learn.hashicorp.com/consul/getting-started/install
- Minikube install: https://learn.hashicorp.com/consul/kubernetes/minikube
- Kubernetes install: https://learn.hashicorp.com/consul/kubernetes/kubernetes-deployment-guide
Documentation
Full, comprehensive documentation is available on the Consul website:
Contributing
Thank you for your interest in contributing! Please refer to CONTRIBUTING.md for guidance.