Rack Leader Controller; Multiple Chassis Manager Connections - Silicon Graphics ICE X User Manual

3: System Overview

Rack Leader Controller

Multiple Chassis Manager Connections

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administrative servers used in a system. In high-availability (HA) administration server
configurations, two servers are paired together. The primary admin server is backed up by an
identical "backup" admin server. The second (backup) server runs the same system management
image as the primary server.
The server is used to install SGI ICE X system software, administer that software and monitor
information from all the compute blades in the system. Check with your SGI sales or service
representative for information on "cold spare" options that provide a standby administration
server on site for use in case of failure.
The administration server on ICE X systems is connected to the external network. All ICE X
systems are configured with dedicated "login" servers for multiple access accounts. You can
configure multiple "service nodes" and have all but one devoted to interactive logins as "login
nodes", see the "Login Server Function" on page 42 and the "I/O Gateway Node" on page 43.
A rack leader controller (RLC) server is generally used by administrators to provision and manage
the system using SGI's cluster management (CM) software. One rack leader controller is required
for every eight CMC boards used in a system and it is a non-blade "stand-alone" 1U server. The
rack leader controllers are guided and monitored by the system administration server. Each RLC
in turn monitors, pulls and stores data from all the blade enclosures within the logical rack that it
monitors. The rack leader then consolidates and forwards data requests received from the blade
enclosures to the administration server. A rack leader controller also supplies boot and root file
sharing images to the compute nodes in the enclosures.
Note that a high-availability RLC configuration is available that doubles the number of RLCs used
in a system. In high-availability (HA) RLC configurations, two RLCs are paired together. The
primary RLC is backed up by an identical "backup" RLC server. The second (backup) RLC runs
the same fabric management image as the primary RLC. Check with your SGI sales or support
representative for configurations that use a "spare" RLC or administration server. This option can
provide rapid "fail-over" replacement for a failed RLC or administrative unit.
In multiple-rack configurations the chassis managers (up to eight CMCs) may be interconnected
to the rack leader controller (RLC) server via one or two Ethernet switches. Figure 3-5 shows an
example diagram of the CMC interconnects between two ICE X system racks using a virtual local
area network (VLAN). This example is not applicable to M-Cell closed-loop systems. For more
information on these and other topics related to the CMC, see the SGI Management Center
007-5806-004