Hitachi MP-96RD625-01 manual System Option Modes, Mode Description

–Medium: The speed of the initial copy activity is faster than Low and slower than High.

If you want to specify Medium, please ensure that the amount of update I/Os (i.e., write requests from hosts to primary data volumes) is 10 MB/s or less per one parity group. If it exceeds 10 MB/s, data volume pairs may become split (suspended).

•High: The speed of the initial copy activity is faster than Low and Medium.

If you want to specify High, please ensure that update I/Os (i.e., write requests from hosts to primary data volumes) will not occur. If update I/Os occur, data volume pairs may become split (suspended).

Note: The secondary storage system administrator cannot specify this option.

•Unit of Path Watch Time: Allows you to specify the unit of path watch

time. You can specify one of the following: minute, hour, or day.

•Path Watch Time: Allows you to specify the interval from when a path gets blocked to when a mirror gets split (suspended).

This value must be within the range of 1 to 59 minutes, 1 to 23 hours, or 1 to 30 days. You can specify a numeric value in Path Watch Time.

Note: Make sure that the same interval is set to both the master and restore journal groups in the same mirror, unless otherwise required. If the interval differs between the master and restore journal groups, these journal groups will not be suspended simultaneously. For example, if the interval for the master journal group is 5 minutes and the interval for the restore journal group is 60 minutes, the master journal group will be suspended in 5 minutes after a path gets blocked, and the restore journal group will be suspended in 60 minutes after a path gets blocked.

Caution: If the DKCMAIN microprogram version is 50-05-03-00/00 or higher, the path watch time setting does not take effect because the system option mode 449 is set to ON at the factory setting. To make the path watch time setting take effect, please ask the Support Center to set the mode 449 to OFF.

Note: If you want a mirror to get split (suspended) immediately after a path gets blocked, please ask the Support Center to set the system option mode 448 to ON and set the system option mode 449 to OFF. For detailed information about the modes 448 and 449, see Table 6-2.

Table 6-2 System Option Modes

Mode

Description

448ON: If the SVP detects a blocked path, the SVP assumes that an error occurred, and then immediately splits (suspends) the mirror.

OFF: If the SVP detects a blocked path and the path does not recover within the specified period of time, the SVP assumes that an error occurred, and then splits (suspends) the mirror.

Note: The mode 448 setting takes effect only when mode 449 is set to OFF.

6-18 Chapter 6 Configuring Journal Groups

Hitachi Universal Replicator for IBM /OS User’s Guide