Hp StorageWorks XP Remote Web Console Software Manuel d'utilisateur télécharger pdf (Page 197)

11 Disaster Recovery Operations

The type of disaster and the status of the URz volume pairs will determine the best approach for disaster

recovery. Unfortunately, some disasters are not so “orderly” and involve intermittent or gradual failures

occurring over a longer period of time. The user should anticipate and plan for all types of failures

and disasters.

The major steps in preparing for disaster recovery are:

1. Identify the journal groups and data volumes that contain important ﬁles and data (e.g. DB2 log

ﬁles, master catalogs, key user catalogs, and system control datasets) for disaster recovery.

2. Install the XP Remote Web Console PC and URz hardware and software, and establish Universal

Replicator operations for the journal groups and data volumes identiﬁed in step (1).

3. Establish ﬁle and database recovery procedures. These procedures should already be

established for recovering data volumes that become inaccessible due to some failure.

4. Install and conﬁgure error reporting communications (ERC) between the primary and secondary

sites.

File and Database Recovery Procedures

When the primary storage system (or secondary storage system for URz) suspends a URz pair due to an

error condition, the primary storage system or secondary storage system sends sense information with unit

check status to the appropriate host(s). This sense information is used during disaster recovery. You must

transfer the sense information to the secondary site via the error reporting communications (ERC).

NOTE:

Make su

re that the primary and secondary storage systems are conﬁgured to report the service-level

SIMs to the host.

When the primary or secondary storage system suspends a URz pair due to a disaster, the secondary

data volume may contain in-process data. A data set could be open, or transactions may not have

completed. Therefore, you need to establish ﬁle recovery procedures. These procedures should be the

same as those used for recovering data volume that becomes inaccessible due to control unit failure.

URz does not provide any procedure for detecting and retrieving lost updates. To detect and recreate lost

updates, you must check other current information (e.g., database log ﬁle) that was active at the primary

site when the disaster occurred. The journal log ﬁle entries of most DBMS have the same system TOD clock

information that is used for the I/O time-stamps (when timer type = system). The URz group consistency

time can be extremely useful when performing this detection and retrieval. Since this detection/retrieval

process can take a while, your disaster recovery scenario should be designed so that detection/retrieval

of lost updates is performed after the application has been started at the secondary site.

For details on the timer type option, see “Timer Type Option” on page 31.

You should prepare for ﬁle and database recovery by using:

• Files for ﬁle recovery (e.g., database log ﬁles which have been veriﬁed as current).

• Thesense informationwithsystemtimestamp whichwillbetransferred via ERC.

Important: Remote copy and disaster recovery procedures are inherently complex. Consult your HP

account team on sense-level settings and recovery procedures. See Chapter 14 on page 213 for

informationonrecoveringapinnedtrack on a URz volume

Hitachi Universal Replicator for z/OS user guide for XP12000/XP10000 Disk Arrays and SVS 200

197

1 2 ... 192 193 194 195 196 197 198 199 200 201 202 ... 218 219

Commentaires sur ces manuels

Pas de commentaire

Hp StorageWorks XP Remote Web Console Software Manuel d'utilisateur Page 197

Commentaires sur ces manuels

Produits connexes et manuels pour Stockage Hp StorageWorks XP Remote Web Console Software