public void saveToCredentialStore(CredentialStoreService credentialStoreService) {
    try {
      credentialStoreService.setCredential(null, ALIAS, this, CredentialStoreType.PERSISTED);
    } catch (AmbariException e) {
      throw new AmbariRuntimeException("Cannot save agent encryption key: " + e.getMessage(), e);
    }
  }
The encryption key which is used to encrypt sensitive data in agent config updates.
This key is shared with the agent so that it can decrypt the encrypted values.
ambari-server/src/main/java/org/apache/ambari/server/agent/AgentEncryptionKey.java