HP XP7 for Compatible FlashCopy Mirroring User Guide (TK940-96001)

Even if the pool is in a 100% used state (area becomes insufficient), you can create a relationship
in which the T-VOL is a TSE-VOL. However, when write processing is done to the S-VOL for the
relationship in this situation, the relationship enters the Failed state.
Managing failed states
Because of running short of physical capacity in a pool that is allocated to one or more TSE-VOLs,
the data copy to the FC T-VOL before updating the S-VOL fails, resulting in that FC relationship
entering the Failed State. Once the FC relationship enters the Failed State, any Read/Write
operations performed to the T-VOL will not be available until the relationship is released. Read/Write
operations to the S-VOL remain available, but the data is not copied to T-VOL.
To restore the FC relationship from a Failed state, the relationship must be released.
Pool capacity warning to the host
When the used capacity of a pool that is associated with TSE-VOL exceeds the threshold value
that is set by the user, a warning message is issued to the mainframe host.
Examples of warning messages include the following:
• If the user sets the warning threshold at 70% and the pool usage capacity exceeds this
threshold, the following warning message is issued:
REPOSITORY VOLUME WARNING: AT 30% CAPACITY REMAINING
• If the user sets the exhaustion threshold at 80% and the pool usage capacity exceeds this
threshold, the following warning message is issued:
REPOSITORY VOLUME WARNING: AT 20% CAPACITY REMAINING
• If the pool usage rate reaches 100%, the following warning message is issued:
REPOSITORY VOLUME EXHAUSTED
The above message is issued regardless of FCSE relationships when I/O operation is performed
on a single TSE-VOL.
Messages are reported to all hosts in which one of the following volumes is online. If one host has
more than one such volume, only one of the volumes is mentioned in the message.
• TSE-VOL (FCSE target volume or volume in Simplex (unpaired) status) associated with the pool.
• Source volume in FCSE relationship.
Notes when sharing pool with THP V-VOL
TSE-VOL and THP V-VOL can share a pool. However, if THP V-VOL and TSE-VOL share a pool,
the capacity of the pool must be designed by estimating the combined capacity of the THP V-VOLs
and the TSE-VOLs.
Establishing relationships for FlashCopy SE
Keeping data consistent while establishing relationships
When you use the FCESTABL command to establish FlashCopy SE relationships, you can keep
data consistent by suspending write operations to S-VOLs using the ACTION parameter. The
ACTION parameter, which is a parameter for the FCESTABL command, is described in the
following table.
Notes when sharing pool with THP V-VOL 93