Red Hat GFS 6.0 -, Administrator'S Manual

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Chapter 1. Red Hat GFS Overview 7
1.4. GFS Software Subsystems
GFS consists of the following subsystems:
•
Cluster Configuration System (CCS)
•
Fence
•
Pool
•
LOCK_GULM
•
LOCK_NOLOCK
Table 1-1 summarizes the GFS Software subsystems and their components.
Software Subsystem Components Description
Cluster Configuration
System (CCS)
ccs_tool
Command used to create CCS archives.
ccs_read
Diagnostic and testing command that is
used to retrieve information from
configuration files through
ccsd
.
ccsd
CCS daemon that runs on all cluster nodes
and provides configuration file data to
cluster software.
ccs_servd
CCS server daemon that distributes CCS
data from a single server to ccsd daemons
when a shared device is not used for storing
CCS data.
Fence
fence_node
Command used by
lock_gulmd
when a
fence operation is required. This command
takes the name of a node and fences it
based on the node’s fencing configuration.
fence_apc
Fence agent for APC power switch.
fence_wti
Fence agent for WTI power switch.
fence_brocade
Fence agent for Brocade Fibre Channel
switch.
fence_mcdata
Fence agent for McData Fibre Channel
switch.
fence_vixel
Fence agent for Vixel Fibre Channel switch.
fence_rib
Fence agent for RIB card.
fence_gnbd
Fence agent used with GNBD storage.
fence_egenera
Fence agent used with Egenera BladeFrame
system.
fence_xcat
Fence agent used with xCAT-managed
cluster.