Hardware Management Console

Hardware Management Console (HMC) is a Physical / Virtual appliance used to manage IBM Systems including IBM System i, IBM System p, IBM System z, and IBM Power Systems. HMC supports command line (ssh) as well as web (https) user interfaces. Using an HMC, the system administrator can manage many systems and partitions. It can also be used for monitoring and servicing a system.

The HMC is a PC connected to the mainframe. zSeries mainframes prior to the IBM System z9 used a modified version of OS/2 with custom software to provide the interface. System z9's HMC no longer uses OS/2, but instead uses a modified version of Linux with an OS/2 lookalike interface to ease transition as well as a new interface. Unlike the previous HMC application on OS/2, the new HMC is web-based which means that even local access is done via a web browser. Remote HMC access is available, although only over an SSL encrypted connection. The web-based nature means that there is no longer a difference between local console access and remote access, which means a remote user potentially has full control if authorized, allowing more flexibility for locating systems within data centers. IBM refers to the new HMC as a "closed platform" which does not allow the user to install software or access the command line interface to increase security and stability. The HMC is also firewalled by default with a minimal number of open ports for remote access.

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