Red Hat CLUSTER SUITE FOR ENTERPRISE LINUX 5.2, Обзор

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Figure 1.17. Creating Logical Volumes
7. Global Network Block Device
Global Network Block Device (GNBD) provides block-device access to Red Hat GFS over
TCP/IP. GNBD is similar in concept to NBD; however, GNBD is GFS-specific and tuned solely
for use with GFS. GNBD is useful when the need for more robust technologies — Fibre Channel
or single-initiator SCSI — are not necessary or are cost-prohibitive.
GNBD consists of two major components: a GNBD client and a GNBD server. A GNBD client
runs in a node with GFS and imports a block device exported by a GNBD server. A GNBD
server runs in another node and exports block-level storage from its local storage (either directly
attached storage or SAN storage). Refer to Figure 1.18, “GNBD Overview” . Multiple GNBD
clients can access a device exported by a GNBD server, thus making a GNBD suitable for use
by a group of nodes running GFS.
Chapter 1. Red Hat Cluster Suite Overview
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