How to troubleshoot the problem of no network after logging into the cloud server?

To troubleshoot the issue of no network after logging into a cloud server, follow these steps:

1. Check Network Configuration:

   • Verify if the server has a valid IP address. Run ip addr (Linux) or ipconfig (Windows) to check.
   • Ensure the subnet mask, gateway, and DNS settings are correct.

2. Test Basic Connectivity:

   • Ping the default gateway: ping <gateway_ip> (Linux/Windows).
   • Ping an external IP (e.g., ping 8.8.8.8) to check if outbound traffic is allowed.

3. Check Firewall Rules:

   • On Linux, inspect iptables or firewalld:

     sudo iptables -L  # Check rules
     sudo systemctl status firewalld  # Verify firewall status
     

   • On Windows, check Windows Defender Firewall settings.

4. Inspect Routing Table:

   • Run route -n (Linux) or route print (Windows) to ensure the default route is set correctly.

5. Verify Cloud Network Settings:

   • Ensure the cloud server is in the correct Virtual Private Cloud (VPC) or subnet.
   • Check if the security group or network ACL allows inbound/outbound traffic.

6. Check for Service Disruptions:

   • If using a cloud provider, verify if there are any network service interruptions in the region.

Example:
If ping 8.8.8.8 fails but ping <gateway_ip> works, the issue may be with the default route or outbound rules.

Recommended Tencent Cloud Services:

• Use VPC to manage subnets and routing.
• Configure Security Groups to control traffic.
• Check Cloud Monitor for network diagnostics.
• Use NAT Gateway if the server lacks a public IP but needs internet access.