HP XC System Software Administration Guide Version 3.0

Other nodes are assigned services. Following are examples of services:
• Compute
Compute nodes run the Simple Linux Utility for Resource Management (SLURM). SLURM enables them
to launch, monitor, and control jobs.
By default, all nodes in the system are compute nodes.
• 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
The login service is assigned to any node in the LVS ring. LVS assigns a user login to one of these nodes
whenever that user requests a login to the system through the system name or Internet Protocol (IP)
address.
A login node requires a connection to the external network.
• I/O service
An I/O node provides I/O services for the system.
The I/O nodes provide access to Storage Area Networks (SANs) connected to the node, access to file
systems that are mounted locally to the node, or both.
An I/O node should reside in the utility cabinet and connect to the root Ethernet switch.
• Network Address Translation (NAT) Server
The NAT server node provides external access to the nodes in the system that do not have an external
network connection.
The system can have multiple NAT servers configured to balance the access to the external network.
• Management Hub Services
The node that provides management hub services is a central point for management daemons, including
those that provide system logs and performance information.
• Load Sharing Facility for High Performance Computing (LSF-HPC) master server
LSF-HPC is an implementation of the Load Sharing Facility (LSF) for HP XC systems.
The node that is assigned this service is responsible for running the LSF-HPC daemons.
• Image server service
The golden client maintains an image of the file system that is the model for all the nodes in the HP XC
system. SystemImager is the underlying technology used to install the HP XC software, distribute the
golden image, and distribute configuration changes. With the SystemImager, you can update every
node with systemwide information, such as user account data.
Note
The golden client and SystemImager are bound to the same node.
• Configuration database server
The node assigned this service is the MySQL configuration database server for this system. For additional
information on the configuration database, see “Understanding the Configuration and Management
Database” (page 29) .
• Dynamic Host Control Protocol (DHCP) server
24 HP XC Administration Environment