Hitachi MP-96RD625-01 manual Remote Copy Operations, Error Reporting Communications ERC

Error Reporting Communications (ERC)

Error reporting communications (ERC), which transfers information between host processors at the primary and secondary sites, is a critical component of any disaster recovery effort. You can configure ERC using channel-to-channel communications, NetView technology, or other interconnect technologies, depending on your installation requirements and standards. Neither URz nor the URz remote console software provides ERC between the primary and secondary sites.

When URz is used as a data migration tool, ERC is recommended but is not required. When URz is used as a disaster recovery tool, ERC is required to ensure effective disaster recovery operations. When a URz pair is suspended due to an error condition, the primary storage system generates sense information which results in an IEA491E system console message. This information should be transferred to the primary site via the ERC for effective disaster detection and recovery.

Remote Copy Operations

Figure 2-5 illustrates the two types of URz remote copy operations: initial copy and update copy.

Primary host

Write instruction

Secondary host

	Obtaining updated
	journal data
Master	Primary
	data
journal
	volume
volume
Obtaining base-journal
Primary storage system

Update copy

Initial copy

Restore

Restore Secondary

journaldata

volumevolume

Secondary storage system

Figure 2-5 Remote copy operations

This section describes the following topics that are related to remote copy operations with URz:

•Initial copy operation (see the next section)

2-18 Chapter 3 Preparing for Universal Replicator z/OS Operations

Hitachi Universal Replicator for IBM /OS User’s Guide