Juniper Networks J-Series - Manual (Page 228)

To modify the encryption key:
1. Enter operational mode in the CLI.
2. To configure a new encryption key in EEPROM and determine the encryption
process, enter one of the
request system set-encryption-key commands described
in Table 103 on page 204. For example:
user@host> request system set-encryption-key
Enter EEPROM stored encryption key:
3. At the prompt, enter the new encryption key. The encryption key must have at
least 6 characters.
Enter EEPROM stored encryption key:juniperone
Verifying EEPROM stored encryption key:
4. At the second prompt, reenter the new encryption key.
206 ■ Encrypting and Decrypting Configuration Files
J-series™ Services Router Administration Guide