Autodesk 15606-011408-9320 - MAP R6.3 CPU MODEL-UPG 4/5 MIN 2 CPUS INITL, User Manual

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Architecture and Performance
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The distributed data model requires less maintenance than the mirrored
systems model. However, this approach is not fault tolerant—if one Autodesk
MapGuide Server goes down, map viewers cannot access the data on that
server. The mirrored systems model is safer than the distributed data model
because it does have fault tolerance, which provides a backup server so that
the data is still available. However, mirrored systems can require more main-
tenance than distributed data systems if you need to update the servers.
The following diagrams illustrate the two different multiple server architec-
tures. In the first diagram, notice that there are three web server computers,
each with its own Autodesk MapGuide Server. Each contains different data.
In this case, requests are distributed among the servers based solely on which
data is requested; if repeated requests are made for the same data, only the
server containing that data will be processing the requests. To make this
model work, you must plan the placement of your data carefully so that
requests are distributed equally among the servers.
Example of distributed data
OLE DB
Attribute Data
MapGuide
Server 1
Web Server 1
MapGuide
Server 2
Web Server 2
MapGuide
Server 3
Web Server 3
...still more
spatial data
...more
spatial data...
spatial
data...
raster data
Map
Agent
Map
Agent
Map
Agent