IBM SC34-7012-01 manual Tier 4-6 solutions

support the XRC DFSMS/MVS host, and one for the recovery 3990, this allows a total of 86 km (53.4 miles) between the 3990s. If you use channel extenders with XRC, there is no limit on the distance between your primary and remote site.

For RRDF there is no limit to the distance between the primary and secondary sites.

Tier 4–6 solutions

This summary shows the three tiers and the various tools for each that can help you reach your required level of disaster recovery.

Figure 25 summarizes the solutions for tiers 4 through 6, and shows the approximate time required for a recovery with each tier of solution.

Tier 4 - 6

4	5	6
Active	2 site/2 phase	Zero data loss
secondary	commit
site. Host-Host	Application	ESCON
file transfer	based
( < 1 d a y )	(< 1 h o u r )	(Instantly)
DFSMSdss	IMS / XRF	3990 model 6 remote copy
DFSMShsm	CICS	- Peer-to-peer remote copy
(ABARS)	DB/2	- Extended remote copy
NETVIEW	Other	Host data compression

Figure 25. Disaster Recovery Tier 4-6: Summary of Solutions

Tier 4 relies on automation to send backups to the remote site. NetView® provides the ability to schedule work in order to maintain recoverability at the remote site.

Tier 5 relies on the two-phase commit processing supported by various database products and your application program's use of these features. Tier 5 requires additional backup processing to ensure that vital data, other than databases, is copied to the remote system.

Tier 6 is divided into two sections: software solutions for specific access methods and database management systems, and hardware solutions for any data.

RRDF can provide very high currency and recoverability for a wide range of data. However, it does not cover all the data in which you may be interested. For example, RRDF does not support load module libraries.

The 3990-6 hardware solution is independent of the data being stored on the DASD. PPRC and XRC can be used for databases, CICS files, logs, and any other data sets that you need to ensure complete recovery on the remote system.

Chapter 19. Disaster recovery 233