Login Mode

Description

Password
You can set the initial password for logging in to the ECS and keep it secure. For Linux, the username is root. For Windows, the username is Administrator.

If you forget the password, perform the following steps to reset it:
1. Locate the target ECS, click More in the Operation column, and select Reset Password.
2. Restart the ECS to apply the new password.

Key pair
A key pair is used for ECS login authentication and is recommended for a Linux ECS.

Before using a key pair, ensure that you have obtained the private key. A private key can be downloaded only once. Keep it secure. You can use a key pair in any of the following ways:
- Use an existing key pair.
- Click Create Key Pair to create one.
- Import a key pair. Actually, the public key will be imported and used together with your obtained private key to authenticate logins.
  Creating a Key Pair
Image password
If you use a Linux private image to create an ECS, you can use the image password for login authentication. Make sure that a password has been set for the selected private image.
Skip
If you did not set a login mode when you create an ECS, you can reset the password on the ECS console by choosing More > Reset Password in the Operation column of the target ECS.

FAQs

How Do I Change the Login Password on an ECS?

When your password is forgotten or about to expire or when you log in to an ECS for the first time, you are advised to change the initial password upon the first login.

Windows ECSs
1. Log in to the Windows ECS remotely.
  For details, see Logging In to a Windows ECS.
2. Press Win+R to start the Run dialog box.
3. Enter cmd to open the CLI window.
4. Run the following command to reset the password. For details about password complexity requirements, see Overview of Password Reset.
  net user Administrator New password
Linux ECSs
1. Use the existing key file to log in to the Linux ECS as user root through SSH.
  For details, see Logging In to a Linux ECS Using an SSH Key.
2. Run the following command to reset the password of user root:
  passwd
  
  To reset the password of another user, replace passwd with passwd username.
3. Enter the new password as prompted. For details about password complexity requirements, see Overview of Password Reset.

How Do I Reset the Password for Logging In to a Windows ECS Without the Password Reset Plug-in Installed?

If your Windows ECS has not had password reset plug-ins installed, you can reset the password by reattaching the system disk.

For details, see Resetting the Password for Logging In to a Windows ECS Without the Password Reset Plug-in Installed.

This method can only be used to change the password of a local Windows account, but not the password of a domain account.

How Do I Reset the Password for Logging In to a Linux ECS Without the Password Reset Plug-in Installed?

If your Linux ECS has not had password reset plug-ins installed, you can reset the password by reattaching the system disk.

For details, see Resetting the Password for Logging In to a Linux ECS Without the Password Reset Plug-in Installed.

This method describes how to reset the password of user root. After resetting the password, you can log in to the ECS, and change the private key or reset the password of a non-root user.

What Should I Do If the System Displays a Message Indicating that the Password Is Incorrect When I Remotely Log In to My ECS?

Check the network configuration of the ECS and determine whether the fault is caused by a Cloud-Init failure.

Verify that the inbound and outbound rules of the security group configured for the ECS allow traffic over port 80.
Figure 1 Port 80
Verify that DHCP is enabled in the subnet where the ECS works.
Figure 2 Checking DHCP status

After verifying the preceding configurations, restart the ECS, wait for 3 to 5 minutes, and remotely log in to the ECS using a password or key.

For details about Cloud-Init functions, see Cloud-Init.

How Can I Obtain the Key Pair Used by an ECS?

If you have created multiple key pairs, you might not know which key pair is the required one for logging in to the target ECS. Then, you can quickly identify the target key pair on the management console.

In the ECS list, select the target ECS.
Click the ECS name and view its key pair on the details page.
The value is the key pair used by the ECS.

Why Is Login to a Linux ECS with a Key File Unsuccessful?

Cause 1: The image used to create the Linux ECS is a private image, on which Cloud-Init is not installed.
Solution: If a private image is created without Cloud-Init installed, the ECS configuration cannot be customized. As a result, you can log in to the ECS only using the original image password or key pair. The original image password or key pair is the OS password or key pair configured when the private image was created.

If the original image password was forgotten or key pair has been lost, use the password reset function available on the Elastic Cloud Server page to reset the password.
Cause 2: Cloud-Init is installed on the image, but the key pair was not obtained during ECS creation.
Solution:
1. Select the target ECS and click Restart to restart it.
2. Use the key file to log in to the ECS again and check whether the login is successful.
  - If yes, no further action is required.
  - If no, contact customer service.