Hello everyone,
I am running a DigitalOcean Ubuntu VPS with x-ui panel and Xray 26.5.9.
I am experiencing an issue with my VLESS TCP setup and I would appreciate any guidance.
Environment:
Configuration:
Server status:
Client:
Problem: The VPN connection is established successfully, but no traffic is passing through the tunnel. As soon as I disconnect the VPN, normal internet works again immediately.
What I have already tested:
Question: What could cause a successful VLESS TCP connection with zero traffic passing through the tunnel?
Thank you in advance for any help.
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Hi there,
First thing to check is whether DigitalOcean’s cloud firewall is allowing traffic on port 36730. The port being open on the OS level via ss -lntp does not mean the cloud firewall is passing it through. Go to Networking > Firewalls in the control panel and confirm that port is explicitly allowed for inbound TCP.
Second, check IP forwarding on the server. Xray needs the kernel to forward packets between interfaces:
sysctl net.ipv4.ip_forward
If it returns 0, enable it:
echo "net.ipv4.ip_forward=1" >> /etc/sysctl.conf
sysctl -p
Third, check your iptables rules. Some setups have a default DROP policy on the FORWARD chain which silently blocks all routed traffic even when the connection itself succeeds:
iptables -L FORWARD -n
If it shows DROP as the default policy, that is your problem.
Fourth, DNS could be the issue. Even if the tunnel is up, if DNS queries are not routing through it, nothing will load. Try hardcoding a DNS server in your client config like 1.1.1.1 and see if that changes anything.
The IP forwarding and iptables FORWARD chain are the most likely culprits based on what you have described.
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