What causes "error writing state: %w" in hashicorp/terraform?

Treat as an out-of-memory condition: reduce state size or raise provider memory limits.

error writing state

Error message

error writing state: %w

What it means

Returned by the tfplugin6 WriteStateBytes handler when writing a received chunk into the in-memory bytes.Buffer fails. bytes.Buffer.Write only errors on a negative byte count or allocation failure, so under normal operation this guard is effectively unreachable; encountering it signals memory exhaustion or stream corruption.

Solutions

Treat as an out-of-memory condition: reduce state size or raise provider memory limits.
If reproducible, capture the chunk size and investigate stream/transport corruption.
Report as a likely bug if it occurs without memory pressure.

Example fix

// defensive guard; practically unreachable
n, err := state.Write(chunk.Bytes)
if err != nil {
    return fmt.Errorf("error writing state: %w", err)
}
// no normal code path triggers this; address OOM/corruption upstream

Defensive patterns

Strategy: try-catch

Try / catch

// Practically unreachable (bytes.Buffer.Write only fails on OOM/negative count).
err := client.WriteStateBytes(ctx, chunks)
if err != nil && strings.Contains(err.Error(), "error writing state") {
    // treat as resource exhaustion; reduce state size or raise limits
    return fmt.Errorf("state write failed (likely OOM): %v", err)
}

Prevention

Size provider memory to hold the largest expected state plus overhead.
Investigate immediately if this fires; it is not a normal operating condition.

When it happens

Trigger: state.Write(chunk.Bytes) returns a non-nil error, which realistically requires OOM/absurd allocation or a corrupted chunk payload producing an impossible write.

Common situations: Extreme memory pressure on the provider process; absurdly large state; corrupted/garbage chunk bytes; not expected in normal operation.

Related errors

AI-assisted analysis of hashicorp/terraform@d32a084675 (2026-08-11). Data as JSON: /api/errors/4676da02cb90e786. Report an issue: GitHub.

Appendix: source

Thrown at internal/grpcwrap/provider6.go:1092

		if err != nil {
			grpcErr = fmt.Errorf("wrapped err: %w", err)
			break
		}
		if expectedTotalLength == 0 {
			// On the first iteration
			expectedTotalLength = chunk.TotalLength // record expected length
			if chunk.Meta != nil {
				// We expect the Meta to be set on the first message, only
				typeName = chunk.Meta.TypeName
				stateId = chunk.Meta.StateId
			} else {
				panic("expected Meta to be set on first chunk sent to WriteStateBytes")
			}
		}

		n, err := state.Write(chunk.Bytes)
		if err != nil {
			return fmt.Errorf("error writing state: %w", err)
		}
		totalReceivedBytes += n
	}

	if grpcErr != nil {
		return grpcErr
	}

	if int64(totalReceivedBytes) != expectedTotalLength {
		return fmt.Errorf("expected to receive state in %d bytes, actually received %d bytes", expectedTotalLength, totalReceivedBytes)
	}

	if totalReceivedBytes == 0 {
		// Even an empty state file has content; no bytes is not valid
		return errors.New("No state data received from Terraform: No state data was received from Terraform. This is a bug and should be reported.")
	}

	resp := p.provider.WriteStateBytes(providers.WriteStateBytesRequest{

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