Introduction
CMOSPWD is a command in the IBM i operating system (formerly known as AS/400) that is used to manage the password for the CMO (Common Management Operations) account. The CMO account is a privileged user profile that provides access to a wide range of system administration functions, including certain remote console operations and configuration tasks that require elevated privileges. The CMOSPWD command allows authorized users to set, change, or reset the CMO password, ensuring that the account remains secure while still enabling necessary administrative operations.
History and Background
Origins of the CMO Account
The CMO account was introduced in the early 1990s as part of IBM i's effort to centralize system administration and to provide a consistent, secure mechanism for remote and local administrative access. Prior to its introduction, system administrators relied on a variety of local user profiles with differing levels of access. The CMO account standardized this by offering a single, highly privileged profile that could be used for both console and network-based administration.
Evolution of CMOSPWD
Initially, the password for the CMO account was stored in a flat file and could be set only by using low-level commands that required direct file manipulation. As security requirements increased, IBM introduced the CMOSPWD command to provide a higher-level interface for password management. The command incorporated additional features such as key file support and compliance with password complexity requirements mandated by industry regulations. Over successive releases of IBM i, CMOSPWD has been updated to support new password hashing algorithms and to integrate with modern authentication services such as LDAP and Kerberos.
Key Concepts
Privilege Level and Scope
The CMO account is a member of the QTMHADMIN group, giving it the ability to modify system configuration, manage user profiles, and perform diagnostic tasks. Unlike standard user profiles, the CMO account is not intended for interactive use by end users but rather for automated scripts, remote consoles, and system recovery processes. Because of this privileged status, the integrity of its password is paramount; compromise of the CMO password can lead to full system takeover.
Password Storage and Protection
In IBM i, passwords are not stored in plain text. The CMO password is kept in a protected system file, usually named CMO.PWD, located in the QSYS.LIB library. The file is encrypted using a symmetric key that is unique to each system installation. The CMOSPWD command accesses this file indirectly, ensuring that the raw password is never exposed to user programs. In addition to encryption, the password is hashed with a salted cryptographic hash function (typically SHA‑256 or SHA‑3, depending on the system configuration) before being written to the file. This combination of encryption and hashing protects against both file-based attacks and replay attacks.
Password Complexity and Policy
IBM i enforces password complexity requirements for the CMO account through the IBM i Security Configuration Guide. The default policy requires an eight-character password that includes at least one uppercase letter, one lowercase letter, one numeric digit, and one special character from the set !@#$%^&*(). Administrators can adjust the policy using the *CHGPWD and *CHGPWDPRF commands, which allow them to specify minimum length, character set restrictions, and expiration intervals. The CMOSPWD command respects these policy settings and will reject any password that does not meet the current requirements.
Command Syntax
Basic Form
The fundamental syntax for the CMOSPWD command is:
CMOSPWD PASSWORD(newPassword) KEYFILE(keyFile)
Here, newPassword is the desired CMO password, and keyFile is an optional key file that provides an encrypted representation of the password. When the KEYFILE parameter is omitted, CMOSPWD accepts the clear-text password directly, provided it satisfies the complexity policy.
Advanced Options
Additional parameters can be supplied to control the behavior of the command:
RESET– Resets the CMO password to a system-generated random value and displays it on the console. This option should be used with caution because the random password is not stored in a file until the command completes.VALIDITY(duration)– Sets a validity period for the password. After the specified duration, the password will automatically expire and require renewal.LOG– Logs the password change event to the IBM i audit trail. This option is useful for compliance purposes.QUIET– Suppresses confirmation prompts. Use this in batch or scripted environments where interactive input is not possible.
Applications
System Administration
System administrators frequently use CMOSPWD to rotate the CMO password on a scheduled basis, ensuring that the account remains secure against brute-force attempts. Password rotation scripts can invoke CMOSPWD with the RESET option to generate a new random password, then store the value in a secure vault for future use. The LOG parameter ensures that each rotation is recorded for audit purposes.
Remote Console Access
Many IBM i deployments provide remote console access through the IBM i Access Client Solutions (ACS) or the IBM i Navigator. These tools require the CMO password to establish a secure session. By using CMOSPWD to manage this password centrally, administrators can guarantee that remote access remains controlled and that only authorized users can obtain the credentials. The password can be distributed to trusted console software via secure configuration files or via an authentication proxy that retrieves the value from a vault.
Automated Deployment and Recovery
In disaster recovery scenarios, automated scripts often need to perform high-level administrative tasks such as restoring a database snapshot or restarting a system service. These scripts rely on the CMO account to execute privileged commands. CMOSPWD can be integrated into the recovery workflow to provide a temporary password that is valid only for the duration of the recovery process. After completion, the script can invoke CMOSPWD to reset the password to a known secure value, minimizing the exposure window.
Security Implications
Risk Mitigation Strategies
Because the CMO account has extensive privileges, its password must be protected using best practices:
- Least Privilege – Only designate a minimal set of administrators with the authority to invoke CMOSPWD.
- Strong Password Policy – Enforce complexity, rotation, and expiration policies using IBM i’s password management framework.
- Secure Key Management – When using key files with CMOSPWD, store the keys in a hardware security module (HSM) or an enterprise key management system.
- Audit Trail – Enable logging for all CMOSPWD operations and regularly review the audit logs for anomalous activity.
Common Pitfalls
Administrators may inadvertently expose the CMO password by:
- Storing Clear-Text Passwords – Avoid placing the password in script files, configuration files, or email. Use secure vaults instead.
- Using Default Passwords – Never rely on the system-generated default password; always change it immediately after installation.
- Ignoring Expiration Policies – Failing to enforce password expiration can allow stale credentials to remain valid indefinitely.
Integration with Other IBM i Features
IBM i Access Client Solutions (ACS)
ACS includes a built-in password manager that can retrieve the CMO password from the system’s key store. When a user connects to a remote console, ACS can request the CMO password from the CMOSPWD command indirectly via the IBM i Manager. This integration ensures that the password is not exposed on the local machine and that it can be refreshed automatically when the password changes.
IBM i Navigator
The Navigator’s Administration console provides a graphical interface for managing system profiles. Under the Security tab, administrators can view the status of the CMO account and trigger a CMOSPWD operation. The Navigator captures the output of the CMOSPWD command and displays it in a secure dialog, ensuring that the password is not written to the console log.
Alternatives and Related Commands
While CMOSPWD is the dedicated command for CMO password management, IBM i offers several other commands that can affect privileged passwords:
- *CHGPWD – Changes the password for a specified user profile, which can be used to manage the CMO password if the profile is not explicitly designated for CMO use.
- *CHGPWDPRF – Modifies the password policy for a user profile or profile group.
- *SAVSPS – Saves a system image to a secure backup medium, which can be used to restore the CMO password if it is lost.
- *CHGUSRPRF – Alters attributes of a user profile, such as the password expiration date.
Frequently Asked Questions
Can I set the CMO password without using a key file?
Yes. The CMOSPWD command accepts a clear-text password as a parameter, provided it meets the current complexity policy. However, using a key file is recommended for automated scripts to avoid exposing the password in clear text.
What happens if the CMO password is forgotten?
If the CMO password is lost, an administrator with *SYSADMIN authority can use the CMOSPWD command with the RESET option to generate a new random password. The new password will be displayed on the console, and the old password will be invalidated immediately.
Troubleshooting
Common issues with CMOSPWD include syntax errors, password policy violations, and permission errors. Users should verify that the command syntax matches the IBM i version documentation. If the password does not meet complexity requirements, the command will return an error indicating the specific policy violation. Permission errors usually indicate that the invoking user lacks the necessary authority to modify the CMO password; in such cases, the user should be added to the QTMHADMIN group or granted *SYSADMIN authority.
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