Installation as the root user
A non-root user is required for executing software. Therefore, you need to create such a user before the installation.
- If the non-root user is HwHiAiUser, the system will specify it as the execution user by default when you install a software package.
- If the non-root user is not HwHiAiUser, you need to specify an execution user by configuring the --install-username=username --install-usergroup=usergroup parameter when installing a software package.
Installation as a non-root user
The installation user must be the same as the execution user.
- If a non-root user already exists, you do not need to create a new one.
  If you want to use a new non-root user, create one and set a password for it by performing the following operations as the root user:
  1. Create a non-root user.
```
groupadd usergroup
useradd -g usergroup-d /home/username -m username
```
  2. Set a password for the user.
```
passwd username
```
- An execution user is specified for a driver only and will also be applied to firmware. You cannot specify an execution user for firmware separately.
- username indicates the username of the non-root user to be created. Replace it with an actual username, for example, HwHiAiUser.
- Permission control may cause security risks. You are not advised to add the new user to the root user group.
- Do not disable login authentication for the HwHiAiUser user.
- The password validity period is 90 days. You can change the password validity period in the /etc/login.defs file or by running the chage command. For details, see Configuring Password Aging.

Configuring Password Aging

For security purposes, run the chage command to set the validity period of a password.

The command is as follows:

chage [-m minimum days] [-M maximum days] [-d last day] [-I inactive] [-E expiration date] [-W warning days] user

Table 1 describes the parameters.

**Table 1** Password aging
Parameter	Description
-m	Minimum number of days between password changes. 0 indicates that you can change your password at any time.
-M	Maximum number of days during which a password is valid. -1 will remove checking a password's validity and may cause security risks. You are not advised to set this parameter to -1 unless extremely necessary.
-d	Date of the last password change.
-I	Number of inactive days after the password expiration before the account is locked.
-E	Date on which the account is locked.
-W	Number of days of warning before a password change is required.
-l	Lists account aging information.

Table 1 lists only common chage parameters. You can run the chage --help command to learn other chage parameters.
The date is in the format of YYYY-MM-DD. For example, chage -E 2019-12-01 test indicates that the test user will expire on December 1, 2019.
If user is not specified, the settings will be applied to the root user by default.

For example, to make the test user expire on December 31, 2019, run the following command:

chage -E 2019-12-31 test

Creating an Execution User

Configuring Password Aging