Cloud Server: Troubleshooting

Identifying and Fixing Errors in Case of a Server Failure

This article explains how to collect information about your system and possible sources of errors when your Cloud Server fails.

If your server is no longer accessible, first try to narrow down the possible source of the error(s) step by step in order to identify and solve the problem as quickly as possible. Proceed as follows:

Restart the Server and Check the SSH or Remote Desktop Connection


Depending on the operating system and configuration of the server, this process can take up to 10 minutes.


If you receive the message that the password is incorrect, check the credentials in the Cloud Panel and reset the root password (Linux) or the administrator password (Microsoft Windows) if necessary.

Check the Log Files

If you can establish a connection to your server, check the server's log files. When troubleshooting, consider updates and configuration changes that may have been made recently.

If you cannot connect to your server, continue to the next step.

Check the Firewall Policy and Rules

  • In the Infrastructure > Servers section of the Cloud Panel, check which firewall policy is assigned to the server. 

  • In the Network > Firewall Policy section, check if the required ports have been opened in the assigned firewall policy. If necessary, assign the correct firewall policy to the server or create the necessary rules for the port releases in the assigned firewall policy, such as port 22 for SSH or port 3389 for RDP.

  • Try again to connect to the server via SSH  (Linux) or Remote Desktop (Microsoft Windows Server).

Perform a Port Scan

If you cannot connect to the server after checking and adjusting the firewall policy in the Cloud Panel, perform a port scan. To perform a port scan on your local computer, enter the appropriate command in the terminal (Linux) or in the Powershell (Microsoft Windows):



[root@localhost ~]# nc -v 22
Microsoft Windows


[root@localhost ~]# Test NetConnection -Port 22


If the required ports are still blocked after the firewall policies have been checked and adjusted, you will need to check the firewall settings in your operating system.

Check the Configuration of the Server

If you cannot connect to the server, log on to the server using the KVM console. Then check the firewall configuration and network settings of the server.

For the most important commands you need to check the network configuration and firewall configuration, see the following article:

Checking the firewall configuration and the network settings (Linux)

Use Knoppix for Data Rescue If Access to the Operating System Is Not Possible

If you cannot access the operating system, you can boot your server using the Knoppix DVD and mount the partitions so that you can access the data via SSH or SFTP. Simply follow these steps:

In the Cloud Panel, insert the Knoppix DVD in the Infrastructure > Server section and restart the server. The server now boots with the Knoppix-DVD. The server now boots with the Knoppix DVD. After the restart of the the server, you can access Knoppix through the KVM console and create a backup of your data or change the configuration of your server. Step-by-step instructions can be found here:

Cloud Server: Use Knoppix for data recovery


If your server cannot boot with the Knoppix DVD or if you have problems with troubleshooting, please contact support.