besttrace.sh: One-Command Return Route Testing

besttrace.sh is a very popular one-click return-route (回程) testing script for Linux. The name usually refers to two different but related projects: one maintained by “搬瓦工中文网” (Bandwagon Host Chinese site) and another maintained by tomdiary on GitHub. Both aim to simplify return-route testing with similar core functionality.

Core Features and Benefits

The core value of besttrace.sh is reducing complex return-route testing to a single command with automatic analysis.

One-click execution: No complex installation required; one command starts the test.
Smart line analysis: The biggest highlight. The script automatically identifies line types (such as CN2 GIA, CMIN2, Unicom 9929, etc.) and labels them directly in the output, making line quality obvious at a glance.
Comprehensive test nodes: Covers China Telecom, China Unicom, China Mobile, and CERNET, with test points in major cities like Beijing, Shanghai, and Guangzhou.
Summary report: Generates a summarized result after testing, saving you from manually analyzing routes hop by hop.
Advanced underlying engine: Uses the NextTrace traceroute engine with a high-precision IP database to accurately show the geolocation and ISP of every hop.

Quick Start: Installation and Usage

Both scripts are very easy to install and use.

Option 1: 搬瓦工中文网 Maintained Version

The most common version online.

Official site: https://besttrace.sh
One-click command (recommended): run it in your VPS SSH terminal as root or a user with sudo privileges:
```
wget -qO- besttrace.sh | bash
```
Note: If wget is not found, install it first via your package manager (e.g., yum install wget or apt install wget).

After running, the script prompts you to choose a test mode:

请选择测试模式：
0. 测试所有节点（默认-直接回车）
1. 仅测试电信（ChinaTelecom）
2. 仅测试联通（ChinaUnicom）
3. 仅测试移动（ChinaMobile）
4. 仅测试教育网（CERNET）
5. 自定义IP测试（自动识别运营商）
请输入选项[0-5]：

Enter the corresponding number and press Enter to start the test.

Option 2: tomdiary/besttrace (GitHub Maintained)

An open-source project continuously updated on GitHub.

GitHub: https://github.com/tomdiary/besttrace

One-click command (recommended):

bash <(curl -Ls "https://raw.githubusercontent.com/tomdiary/besttrace/main/main.sh")

Common options:
- -6: Test IPv6 routes.
- -l en: Switch output language to English.
- -i zc: Switch node data source.

Examples:

# Default test (IPv4, Chinese)
bash <(curl -Ls "https://raw.githubusercontent.com/tomdiary/besttrace/main/main.sh")

# Test IPv6 routes
bash <(curl -Ls "https://raw.githubusercontent.com/tomdiary/besttrace/main/main.sh") -6

Interpreting the Results

After the script finishes, the output clearly shows routing information for every hop with intelligent analysis.

Detailed traceroute: Lists every hop a packet passes through, including IP address, geolocation, and latency.
Smart line analysis: After the traceroute, the script gives a summary line judgment. For example:
```
>>> [智能分析] 线路判定 (目标: CT)：
类型：电信 163 骨干网 (AS4134)
```
If you see a marker like [CN2-BackBone], it usually means the route traverses a high-quality CN2 line.

In short, besttrace.sh reduces complex return-route testing to a single command with automatic analysis, making it ideal for quickly evaluating a VPS’s return-route network quality.