Troubleshooting problems connecting to a Linux Instance

If you are having trouble connecting to the Linux instance, please read the following for the solutions!

First of all, please make sure that the public IP address is bind to your cloud server and the status of the instance is running. You can connect to the Linux instance via VNC. For further information, please refer to "How to use a Linux Server."

Troubleshooting problems connecting to a Linux Instance

1. Is it normal to obtain the internal IP Address of the host?

Error: Unable to remote the host
Solution: Connect to the host through VNC and check the host's network card information to see if the internal IP address is obtained.
Steps: Check the cloud server console-intranet IP, for example, the intranet IP is [192.168.0.171]

Click "More Actions" and then select the [Connect] to connect to the Linux cloud server through VNC.

Enter the account name "root" and the operating system password to log in.

Enter the ifconfig command and check the cloud server network card's information to see if the intranet IP is obtained. If the internal network IP [192.168.0.171] appears, then the intranet IP is normal.

Ping www.google.com to test network connectivity.
Execute the ping www.google.com command. If the following figure appears, it means that the host can access the external network.

If the host cannot access the external network, ping the internal gateway and external gateway of the node (such as the United States) from the host. The cloud server gateways of each region will be different. You can consult customer service or submit a ticket to obtain the corresponding cloud server gateway information.

If you are located locally, you can also ping the intranet gateway and extranet gateway of a node (ex: United States) to verify your local operator's connectivity to our service gateway.

2. Is the configuration of the firewall correct?

First, you will need to check whether the firewall configuration rules are correct. For example, we tried to configure inbound rules and access port 80. However, we accidentally configured as an outbound rule. Which end up we are unable to access port 80.
**Please note that if the firewall is configured correctly, but you still cannot access the port, please submit a ticket or contact the customer service.

3. Network Security Group Rules

Error: Unable to connect to the cloud server, and have checked the firewall and internal IP configuration is correct. Yet, still unable to connect to the cloud server.
Possible Reason: The cloud server security group's default public network rule is deleted, or the port service is not available in the cloud server.
Solution: Reconfigure the cloud server's network security group rules, add inbound ICMP protocol, and open port 22 and port 3389. If you want to see which ports are available on the cloud server, execute the netstat -ant command line to see the ports.

4. Failed to Access Remote Port

Possible Reasons: 1. The host status is off 2. The remote port is modified 3. The operator blocks the IP.

5. High CPU Usage

Error: There is a high CPU usage, which causes the system cannot be connected remotely.
Solution: Run the top command to view the loading status of the program. If the application has many disk access, network access behavior, and high computing demand, then a high CPU usage is normal. Try to upgrade the instance specifications to solve the resource bottleneck problem.

Finally, try to restart the instance.
The restart operation will stop the instance from working. Please proceed with caution.
Note: Before restarting the instance, you need to create a snapshot of the instance for data backup or system rollback.
Restart the instance in the console. After restarting the instance, please try to connect the instance again.

After all the troubleshooting above, if the ECS instance still cannot be connected, please record the troubleshooting results, related log information or screenshots, host password of the preceding steps, and contact our technical support.

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Troubleshooting problems connecting to a Linux Instance