V2ray Slow Dns Server -

Prerequisites

• A server with a compatible operating system (e.g., Ubuntu, CentOS).
• Basic knowledge of Linux commands.
• V2Ray installed on your server.
• Access to your server via SSH.

Slow Speeds: Because DNS is mostly UDP Port 53 and involves high overhead for data tunneling, speeds will naturally be lower than standard VPN protocols. Connection Fails:

"dns": 
  "queryStrategy": "UseIP"  // Bad for slow networks
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 v2ray slow dns server

On V2Ray Configuration: Make sure to update the DNS settings within your V2Ray configuration file (config.json or similar) to use your preferred DNS servers.

"address": "223.5.5.5",
        "domains": ["geosite:cn", "geosite:apple"],
        "expectIPs": ["geoip:cn"]
      ,
      "localhost"
    ],
    "queryStrategy": "UseIPv4",
    "cacheSize": 2048,
    "minTtl": 60,
    "maxTtl": 3600,
    "disableCache": false,
    "disableFallback": false
  ,
  "routing": 
    "rules": [

Check system DNS resolver: On Linux, systemd-resolved can conflict. Stop it or set nameserver 127.0.0.1 in /etc/resolv.conf.
MTU issues: If V2Ray uses UDP-over-TCP (e.g., VMess + mKCP), large DNS packets may fragment. Lower MTU.
Concurrency limit: V2Ray handles ~512 concurrent DNS queries by default. Under heavy load (e.g., torrent with thousands of domains), increase cacheSize and use a local resolver like dnscrypt-proxy as a forwarder.
Firewall inspection: Some corporate/ISP firewalls delay DNS responses they can’t decrypt. Switch to DNS over TLS (DoT) or DoH exclusively.