To ensure system security, you are advised to use the key authentication mode to authorize the user who attempts to log in to a BMS. Therefore, you must use an existing key pair or create a new one for remote login authentication.
If no key pair is available, create one that contains a public and a private key used for login authentication. You can use either of the following methods:
PuTTYgen is a tool for generating public and private keys. You can obtain the tool from https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html.
If a key pair is available locally, for example, generated using PuTTYgen, you can import the public key on the management console so that the system maintains the public key file. For details, see Import a Key Pair.
The BMS console is displayed.
An automatically populated key name consists of KeyPair- and a 4-digit random number. Change it to an easy-to-remember one, for example, KeyPair-xxxx_bms.
You can save the private key file only once. When you create a BMS, provide the key pair name. Each time you log in to the BMS using SSH, you need to provide the private key.

The key generator automatically generates a key pair that consists of a public key and a private key. The public key is that shown in the red box in Figure 2.
Do not save the public key by clicking Save public key. Storing a public key by clicking Save public key of PuTTYgen will change the format of the public key content. Such a key cannot be imported to the management console.
The format in which to save your private key varies depending on application scenarios: To ensure BMS security, you are limited to downloading the private key only once.
When you are required to log in to a Linux BMS using PuTTY, you must use the .ppk private key. To save the private key in .ppk format, perform the following operations:
When you are required to log in to a Linux BMS using Xshell or attempt to obtain the password for logging in to a Windows BMS, you must use the .pem private key for authentication. To save the private key in .ppk format, perform the following operations:
If you use this private file to obtain the password for logging in to a Windows BMS, when you choose Export OpenSSH key, do not configure Key passphrase. Otherwise, obtaining the password will fail.
If you store a public key by clicking Save public key of PuTTYgen, the format of the public key content will change. Such a key cannot be imported to the management console. To resolve this issue, obtain the public key content in correct format and import the content to the management console. For details, see What Do I Do If a Key Pair Created Using PuTTYgen Cannot Be Imported to the Management Console?
The BMS console is displayed.

When importing a key pair, ensure that the public key is imported. Otherwise, importing the key pair will fail.
After the public key is imported, you can change its name.
If you no longer need a key pair, you can delete it. After a key pair is deleted, it cannot be restored. However, you can still use the private key saved locally to log in to the BMS, and the deleted key pair is still displayed in the BMS details.
The BMS console is displayed.