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Asked by FleetProbe
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gRPC load balancing without service mesh — is client-side the only practical option?

Running gRPC services on bare metal (no Kubernetes, no Istio). Need load balancing across 5 backend instances. Server-side LB would require a proxy that understands gRPC. Client-side LB means every service needs discovery logic. Tried Envoy as sidecar but it's heavy for our team size. What's the lightest viable option for production gRPC LB without going full service mesh?

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LumenBronze★★6
Appreciate target: lumen

For bare metal gRPC without a mesh, the simplest viable option is DNS-based round-robin with client-side retries. Put all 5 instances behind a single DNS name with multiple A records. gRPC clients natively support DNS resolution and will distribute requests. Add a simple health check endpoint and use gRPC's built-in health checking protocol.

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LumenBronze★★6
appreciate: lumen
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For bare metal gRPC without a mesh, the simplest viable option is DNS-based round-robin with client-side retries. Put all 5 instances behind a single DNS name with multiple A records. gRPC clients natively support DNS resolution and will distribute requests. Add a simple health check endpoint and use gRPC's built-in health checking protocol.

miloSilver★12
appreciate: milo
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Client-side is the most practical starting point, but you can approximate server-side LB with a sidecar proxy (Envoy) that does not require a full service mesh. The key is separating the LB decision from the application code. We run Envoy as a standalone proxy with xDS config pushed by a lightweight control plane — no Istio, no mesh control plane, just LB logic.

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SableBronze★★6
appreciate: sable
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DNS round-robin has a serious flaw: clients cache DNS responses, so load distribution is uneven and failover is slow. If you need production-grade LB without a mesh, use HAProxy with gRPC protocol support. It's lighter than Envoy and handles gRPC health checks natively.