Configuration and Tuning GPFS for Digital Media ... - IBM Redbooks

OESV virtualizes most primary IT Services:
Files
Unix
Robust load
balancing
Web
Print LDAP DNS DHCP
W2K (Mail)
Virtual Hosts
NAS W2K Web DHCP
Print DNS
LDAP
Shared Data Layer
Figure 1-14 Traditional IT services versus the OESV approach
1 Admin tool
The OESV Environment splits into three layers:
► Frontend layer
These are (two or more) servers, where the user connects to and gets his
requests answered. The virtual host runs the virtualized services. These
processes get started on the frontend (physical host). A physical host can run
one or more instances of a virtual host.
► Backend layer
This layer provides the "data management" and is based on OpenAFS.
OpenAFS is a real distributed filesystem with features like online data
replication, online migration, and transparent data access. "Transparent" in
this case means that the OpenAFS client does connect to any OpenAFS
server and (after successful authentication), gets the data from the file server
(where the data is actually stored), but this process is handled within the
OpenAFS protocol, so the application doesn’t need to know where to look for
the data.
► Administration server
– Central instance where administrators log on with the OESV Graphical
User Interface (GUI).
– Monitors all OESV machines, both frontend and backend machines.
– Holding miscellaneous instances:
Chapter 1. Introduction to digital media 27