IBM AS/400e User Handbook Manual page 88

AS/400e Advanced Technology
environments. From its inception, the AS/400 system was architected with reliability and
availability as equal parameters to features like processor speed, memory capability, and
number of disk arms.
AS/400 design and development resources enable high levels of availability in a single
system environment. This highly reliable design has long been used for unplanned
outages by the AS/400 customer. The single-system AS/400 remains the core building
block to repeat and extend functions into other areas of the business.
• Single-system availability management: The AS/400e servers have high-availability
facilities that are fast, automated, and easy to use. AS/400e customers are more likely to
use the best availability practices, which helps them reduce the length of both planned
and unplanned outages. These practices include facilities such as:
– Save-while-active
– Parallel save and restore
– Backup Recovery and Media Services (BRMS) for AS/400
– ADSTAR Distributed Storage Manager for AS/400 V3R1 (ADSM)
– RAID-5 disk parity protection
– Disk mirroring protection
– Automated journal management
– Access path protection
Note: ADSM was withdrawn from marketing on 31 December 1999. Tivoli Systems Inc.,
an IBM company, now offers Tivoli Storage Manager Version 3.7 to replace the ADSM
product set. See Tivoli Storage Management Solutions at:
• Clusters: Cluster technology is implemented on the AS/400 system to provide availability
during both planned and unplanned outages. In today's world, however, it is becoming
increasingly clear that there is no time for any unplanned outages, or planned outages for
that matter. In an AS/400 installation, the lion's share of downtime comes from planned
outages.
Clusters are implemented to reduce downtime due to planned outages and site disasters.
Providing system availability during planned outages results in increased unplanned
outage coverage as a side benefit.
AS/400 investment in cluster technology. Significant advanced features and functions
were introduced in V4R4 that put the AS/400 system in a leadership position.
Cluster technology has been around for many years, but only recently have common
terms and concepts begun to emerge. In the case of the AS/400 system, it has adopted
these concepts and integrated the infrastructure needed to achieve a level of
standardization, an advance of cluster technology, and the involvement of the Solution
Developer (SD) and the cluster middleware business partner in the total solution. While
the AS/400 provides the basic cluster infrastructure, the cluster middleware business
partner provides data resiliency and the SD provides application resiliency. Together,
these three parts provide the whole solution to continuous availability.
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AS/400e System Handbook
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