# rpc error: code = Unavailable desc = no healthy upstream

- **ID:** `go/grpc-unavailable-load-balancer-no-backends`
- **Domain:** go
- **Category:** network_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

The load balancer or service mesh cannot find any healthy backend instances to route the request.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 1.1 | active | — | — |

## Workarounds

1. **** (85% success)
   ```
   // Configure health checks: grpc.HealthCheck(healthpb.NewHealthClient(conn))
   ```
2. **** (80% success)
   ```
   // Configure destination rules with outlier detection.
   ```

## Dead Ends

- **** — Backends remain unhealthy; client restart doesn't fix server issues. (70% fail)
- **** — New replicas may also fail health checks due to same issue. (60% fail)