Write To Control Blocks Function; Formatting A Specific Ldev - HP XP7 User Manual

Item
Storage system is powered off
and back on
Restrictions

Write to Control Blocks function

The Write to Control Blocks function writes the mainframe system management area to an external
volume.
If the LDEV with the mainframe system emulation type is created on the formatted external volume,
it is recommended that the Write to Control Blocks is set to the format type. If the Write to Control
Blocks is set to the format type, in comparison with the case of the Normal Format setting, the
format time is shortened.
Before using this function, make sure that the external volumes have been formatted by the external
storage system.
CAUTION:
storage system, select Normal Format to perform the format operation. If an option other than
Normal Format is selected, the host may not have access to the formatted external LDEV.
To format the following LDEVs, select Normal Format as the format type:
LDEV which was accessed by hosts
LDEV on which the Write to Control Blocks function was performed

Formatting a specific LDEV

Use this procedure to perform Normal formatting on the volume.
Prerequisites
The Storage Administrator (Provisioning) role is required to perform this task.
Description
groups that have not undergone but can undergo Quick Format, use the following
formula:
72 - X -Y
Where:
Xindicates the number of parity groups on which Quick Format is being performed.
Yindicates the number of parity groups where all volumes are blocked during the Quick
Format.
The Quick Format operation resumes when power is turned back on.
Quick Format cannot be executed on external volumes, virtual volumes, the journal
volumes of Continuous Access Journal Z.
The volume migration feature or the QuickRestore feature cannot be applied to
volumes undergoing Quick Format. When you use RAID Manager to execute the
volume migration operation or the QuickRestore operation on volumes undergoing
Quick Format, EX_CMDRJE will be reported to RAID Manager. In this case, check
the volume status.
The prestaging feature of Cache Residency Z cannot be applied to volumes
undergoing Quick Format.
When it is uncertain whether the external LDEV has been formatted by an external
Formatting LDEVs 53