6-Retry.md

← Timeouts | Retries (中文) | Error Handling →

---

Retry Mechanism

The SDK has built-in automatic retry logic for network errors and throttling. Business logic errors (e.g., parameter errors, resource not found) will not trigger retries.

Enable and Configure Retry

Default

• autoRetry — true
• maxRetries — 3 (total 4 attempts)

const client = new ECSClient({
  region: "cn-beijing",
  // autoRetry: false,  // Completely disable retry
  maxRetries: 5,
});

Retry Conditions

The SDK retries on:

1. Network errors (e.g., ECONNRESET, ETIMEDOUT)
2. HTTP status codes 429, 500, 502, 503, 504

Backoff Strategies

Default

• ExponentialWithRandomJitterBackoffStrategy
• minRetryDelay — 300ms
• maxRetryDelay — 300000ms (5 minutes)

Where minRetryDelay is minimum delay, maxRetryDelay is maximum delay, n is the current retry attempt number (starting from 1).

Strategy	Description	Formula
NoBackoffStrategy	No backoff, retry immediately	delay = 0
ExponentialBackoffStrategy	Exponential backoff	delay = min(minRetryDelay * 2^(n-1), maxRetryDelay)
ExponentialWithRandomJitterBackoffStrategy	Exponential with jitter (default)	base = min(minRetryDelay * 2^(n-1), maxRetryDelay), delay = min(base + random(0, base), maxRetryDelay)

import { StrategyName } from "@volcengine/sdk-core";

const client = new ECSClient({
  region: "cn-beijing",
  strategyName: StrategyName.ExponentialWithRandomJitterBackoffStrategy,
});

Custom Retry Strategy

const client = new ECSClient({
  region: "cn-beijing",
  retryStrategy: {
    minRetryDelay: 500,
    maxRetryDelay: 20000,

    retryIf: (error) => {
      if (error.data?.ResponseMetadata?.Error?.Code === "ResourceIsBusy") {
        return true;
      }
      return false;
    },

    delay: (attemptNumber) => {
      return 1000;
    },
  },
});

---

← Timeouts | Retries (中文) | Error Handling →