Clash — 跨平台、高性能网络代理工具 Clash — Cross-Platform High-Performance Proxy Tool

Steps to install and configure Clash:

1. Choose the right client: Refer to the download matrix on this page. Windows users should choose Clash for Windows; macOS users can select Stash or ClashX Pro; mobile users can use Stash (iOS) or Clash for Android.
2. Download and install: Click the download button for your platform to get the latest package. For GitHub releases, verify the SHA256 checksum to ensure file integrity.
3. Obtain a configuration file: Prepare a YAML-format Clash config file containing proxy server info, routing rules, and DNS settings. You can get one from subscription platforms or write your own.
4. Import the configuration: Open the client and import the config file via the interface (usually supports local file import or subscription URL import). The client will parse it and start the proxy service automatically.
5. Verify connectivity: After starting the proxy, visit a test page to confirm network connectivity and check that routing rules work as expected. Consult the official Wiki or community if issues arise.

Protocols supported by Clash and their characteristics:

1. Shadowsocks (SS): A classic lightweight encrypted proxy protocol, ideal for restricted networks. Clash supports multiple SS encryption methods including AEAD ciphers for data integrity.
2. VMess: The core V2Ray protocol offering robust obfuscation and flexible transport options, suitable for scenarios requiring high anonymity. Clash fully supports VMess over TCP and WebSocket.
3. Trojan: Mimics HTTPS traffic to bypass deep packet inspection (DPI), disguising proxy traffic as normal HTTPS communication. Clash's Trojan support ensures usability under strict censorship.
4. Snell: A lightweight encrypted protocol designed for the Surge ecosystem with low latency and minimal overhead. Clash Premium fully supports Snell v3/v4.
5. WireGuard: A modern VPN protocol known for kernel-level high performance and clean code. Clash supports WireGuard outbound for high-speed stable connections.

Steps to write routing rule configurations:

1. Understand rule structure: Clash rules are defined in the rules field. Each rule includes a match type, match value, and target proxy group. Rules are evaluated top-to-bottom; the first match wins.
2. Choose match types: Supported types include DOMAIN, DOMAIN-SUFFIX, DOMAIN-KEYWORD, GEOIP, IP-CIDR, PROCESS-NAME, and more.
3. Define proxy groups: Create proxy groups in proxy-groups (e.g., "Proxy", "Direct", "Auto-Select") and reference them as rule targets.
4. Write the rule list: Set common domestic domains to DIRECT, point overseas domains to a proxy group, and use a final MATCH rule as the fallback.
5. Test and optimize: Enable logging to observe rule matching behavior, use url-test groups to auto-select the lowest-latency node, and continuously refine rule ordering.

How Fake-IP DNS works and its advantages:

1. Intercept DNS requests: When a client initiates a DNS query, Clash intercepts the request instead of forwarding it to an upstream DNS server for real resolution.
2. Return a fake IP: Clash returns a forged IP from a pre-allocated address pool to the client while recording the mapping between the fake IP and the real domain name.
3. Resolve on connection: When the client establishes an actual connection using the fake IP, Clash restores the real domain from its mapping table and connects through the proxy server.
4. Reduce DNS pollution: Since DNS resolution is handled locally, interference and pollution from intermediate network devices are avoided—especially useful in networks with DNS hijacking.
5. Improve performance: Fake-IP mode reduces DNS round trips, significantly speeding up first-time domain access and lowering perceived latency.

Proxy Group types and configuration methods:

1. Understand group types: Clash supports select (manual), url-test (auto latency-based), fallback (availability failover), load-balance, and relay (chained proxy) group types.
2. Select - manual choice: The most basic type—users manually pick one node from the list, suitable for scenarios requiring a fixed exit IP.
3. url-test - auto testing: Periodically tests latency for all nodes in the group and automatically switches to the lowest-latency node, ideal for speed-conscious users.
4. fallback - availability failover: Tries nodes in priority order and automatically switches to the next when the current one fails, ensuring high availability.
5. load-balance: Distributes traffic across multiple nodes to prevent overloading a single node, suitable for high-traffic stable usage.

Troubleshooting steps and common solutions for connection issues:

1. Check client status: Ensure the Clash client is running and system proxy settings are correctly configured. Review the client log panel for errors, especially config file parsing errors.
2. Verify node availability: Use the client's latency test feature to check each node's connectivity. If all nodes time out, the network may be blocking them or nodes may be expired—try switching nodes or updating subscriptions.
3. Check routing rules: Observe which rule matches the target domain in the logs, and confirm traffic is correctly directed to the intended proxy group. Incorrect rules may cause traffic to go direct and fail to connect.
4. Troubleshoot DNS issues: If domain resolution is abnormal, try switching DNS modes (e.g., from Fake-IP to Redir-Host) or changing the upstream DNS server address.
5. Reset and retry: If all else fails, try restarting the client, re-importing the config file, or using a default config template for minimal testing to isolate the root cause.