Red Hat GLOBAL FILE SYSTEM 4.7, Manual

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might require a combination of configurations shown in the examples.
1.1. Superior Performance and Scalability
You can obtain the highest shared-file performance when applications access storage directly.
The GFS SAN configuration in Figure 1.1, “GFS with a SAN” provides superior file performance
for shared files and file systems. Linux applications run directly on GFS nodes. Without file
protocols or storage servers to slow data access, performance is similar to individual Linux
servers with directly connected storage; yet, each GFS application node has equal access to all
data files. GFS supports over 300 GFS nodes.
Figure 1.1. GFS with a SAN
1.2. Performance, Scalability, Moderate Price
Multiple Linux client applications on a LAN can share the same SAN-based data as shown in
Figure 1.2, “GFS and GNBD with a SAN” . SAN block storage is presented to network clients as
block storage devices by GNBD servers. From the perspective of a client application, storage is
accessed as if it were directly attached to the server in which the application is running. Stored
data is actually on the SAN. Storage devices and data can be equally shared by network client
applications. File locking and sharing functions are handled by GFS for each network client.
Chapter 1. GFS Overview
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