V2Ray caches by default but you can adjust TTL:
"dns":
"cacheSize": 1024,
"minTtl": 60, // minimum cache TTL (seconds)
"maxTtl": 3600
Note: Do not set minTtl too high for dynamic sites.
The review is interesting because "Slow DNS" is almost never the actual problem. It is usually a symptom of:
If you are troubleshooting this, the solution is rarely to change the DNS IP (e.g., switching from Google to Cloudflare), but to change how v2ray queries it (e.g., forcing DNS through the proxy tunnel or using DoH).
Optimizing V2Ray with Slow DNS Servers: A Comprehensive Guide
V2Ray is a popular platform for building and customizing VPN-like services. When configuring V2Ray, users often overlook the impact of DNS settings on performance. A slow DNS server can significantly affect the overall speed and reliability of your V2Ray connection. In this write-up, we'll explore the implications of using slow DNS servers with V2Ray and provide practical advice on optimizing your setup.
The Role of DNS in V2Ray
DNS (Domain Name System) plays a crucial role in resolving domain names to IP addresses, allowing your device to connect to remote servers. In the context of V2Ray, DNS is used to:
The Impact of Slow DNS Servers on V2Ray Performance
Using a slow DNS server can lead to:
Common Causes of Slow DNS Servers
Optimizing V2Ray with Fast DNS Servers
To mitigate the issues associated with slow DNS servers:
Configuring V2Ray with a Fast DNS Server
To configure V2Ray with a fast DNS server:
"dns":
"servers": [
"address": "8.8.8.8",
"port": 53,
"protocol": "udp"
]
Replace the address field with the IP address of your chosen DNS server.
Conclusion
A slow DNS server can significantly impact the performance of your V2Ray connection. By choosing a fast and reliable DNS server, configuring V2Ray to use a local DNS server, and exploring DoH or DoT, you can optimize your V2Ray setup and enjoy a faster, more reliable connection.
Setting up a V2Ray Slow DNS server allows you to tunnel internet traffic through DNS queries, which is often used to bypass restrictive networks or firewalls. This setup is popular for mobile VPN apps like HTTP Custom, ZiVPN, and HTTP Injector. 1. Generate Your V2Ray Slow DNS Account
To get started, you need to create a server account that specifically supports "Slow DNS."
When setting up a configuration that uses (often referred to as DNS-over-UDP or DNSTT), the "draft text" you need typically refers to the server details generated by a provider or the specific JSON configuration structure. 1. Typical V2Ray Slow DNS Configuration Draft If you are manually drafting a configuration for apps like HTTP Custom , your "text" will follow a structure similar to this: Server Name (Name Server): ://example.com (The subdomain pointing to your server) Public Key: your-generated-public-key-here (Used for encryption) DNS Resolver: (Commonly used upstream resolvers) VMess or VLESS 2. Sample V2Ray JSON (DNS Section)
If you are editing the configuration file directly, the DNS block should look like this to ensure traffic is routed correctly: "localhost" "dns-inbound" Use code with caution. Copied to clipboard 3. Steps to Generate Your Own Text
To get the actual credentials for your draft, follow these steps: Visit a Provider: Search for sites like UDP Custom or similar V2Ray/SlowDNS account creators. Create Account: v2ray slow dns server
Choose a server location, enter a username, and complete the CAPTCHA. Copy Details:
The site will generate a "Slow DNS Config" text block containing your NS (Name Server) Public Key 4. Application-Specific Drafts HTTP Custom: You often import a
When using V2Ray, a "slow DNS server" usually refers to a bottleneck in the DNS resolution phase, which can make your entire connection feel sluggish even if your actual bandwidth is high. This happens because every website request must first wait for a response from the DNS server before the V2Ray proxy can even start routing data. 🛑 Why V2Ray DNS Can Feel Slow
The primary reason for slowness is often latency or incorrect routing. If V2Ray is configured to send DNS queries through the proxy tunnel to a far-away server (like a US-based resolver while you are in Europe), the "Round Trip Time" for every single link you click increases significantly.
Outdated Resolvers: Using old or congested server addresses can lead to timeouts.
Cloged Caches: A buildup of local DNS data can slow down the initial lookup process.
Misconfigured Sniffing: If V2Ray's "traffic sniffing" isn't handled correctly, it might resolve DNS multiple times, doubling the wait time. ✅ Best Practices for Speed
To fix a slow DNS experience in V2Ray, experts typically recommend the following:
Use High-Performance Resolvers: Switch from ISP defaults to fast public resolvers like Google (8.8.8.8) or Cloudflare (1.1.1.1).
Deploy CoreDNS: Project V recommends using a professional relay like CoreDNS for better dispatching based on your routing settings.
Configure Internal DNS: Ensure your config.json has a dedicated dns object. This allows V2Ray to resolve domains internally rather than relying on the operating system, which is often slower when a proxy is active. ⚖️ Pros & Cons of Third-Party DNS in V2Ray Speed Resolvers like Cloudflare are built for low latency. Third-party servers can still experience rare outages. Privacy Prevents DNS leaking to your local ISP. You must trust the privacy policy of the DNS provider. Customization V2Ray caches by default but you can adjust
Allows for rules-based routing (e.g., local DNS for local sites). Requires more complex config.json setups.
If you'd like to troubleshoot your specific setup, let me know:
Which V2Ray client are you using (e.g., V2RayN, Shadowrocket, or command line)?
Are you experiencing slowness on all websites or just specific ones?
Do you have a copy of your DNS configuration block? (Please remove any private server IPs/passwords first!) DNS · Project V Official - V2Ray
V2Ray has powerful traffic sniffing capabilities. It intercepts traffic to see if it is HTTP or TLS to extract the real domain name.
When using V2Ray, most users immediately suspect the proxy protocol (VMess, VLESS, Trojan) or the remote server's bandwidth when they experience lag, buffering, or timeouts. However, one of the most common—and most overlooked—culprits is a slow DNS server.
In a typical V2Ray setup, every website you visit requires a Domain Name System (DNS) lookup to translate a human-friendly name (like google.com) into an IP address. If this lookup is slow, your entire connection suffers, regardless of how fast your V2Ray server is.
SSH into your V2Ray server and run:
time nslookup google.com 8.8.8.8
Look at the real time. If it is above 100ms, you have a problem.
Many users test their proxies by going to a "DNS Leak Test" website. Note: Do not set minTtl too high for dynamic sites