HP XC System Software Administration Guide Version 3.2.1

management nodes Perform system management and other functions for the HP XC system.
These functions can include the following:
• Maintain system software images for installing and updating
software on all the nodes in HP XC system
• External network communications
• Networked file system services
• System monitoring
• Resource management
A management node often hosts multiple management functions. A
node is classified based on the service it provides, so it can be known
by multiple names.
A management node is also known as a service node.
planned nodes Exist in the configuration and management database although the
physical nodes are not yet present in the HP XC system. Established
during the initial installation, a planned node is a placeholder for a
node to be installed at a later time.
The benefit of a planned node is that there is less disruption to the HP
XC system for installation and configuration.
The head node is a special management node. It is the node that is installed first. The head node
is established with the alias nh during installation. You can use this alias in command lines when
you want to designate the head node.
In some configurations, the head node provides all management functions; in other configurations,
the head node is one of many management nodes.
Note:
Perform all system administration from the management node that provides the appropriate
service, usually the head node.
1.1.1.2 Local Storage
The local storage for each node holds the operating system, a copy of the HP XC system software,
and temporary space that can be used by jobs. When possible, ensure that jobs that use local
storage clean up files after they are run. You might need to clean up temporary storage on local
machines if jobs do not do so adequately.
1.1.2 Services
A service is the software that runs on a node to provide a given function. In an HP XC system,
nodes are assigned services, like the following examples:
• Compute
Compute nodes run the Simple Linux Utility for Resource Management (SLURM). SLURM
enables them to launch, monitor, and control jobs.
• SLURM central control daemon service
The node that provides this service runs the daemon for the SLURM central control.
• Linux Virtual Service (LVS) Director service
The LVS Director is the node that controls the placement of the user logins on the LVS ring.
• Login
28 HP XC Administration Environment