Suspended pairs – HP StorageWorks XP Remote Web Console Software User Manual

Page 38

Advertising
background image

38

TrueCopy for the XP128/XP1024/XP10000/XP12000

Suspended Pairs

Table 10

on page 39

lists and describes the TC390 suspend types, which indicate the reason for

suspension. A user can suspend aTC390 pair at any time after the initial copy operation is complete. The

user must suspend a TC390 pair to perform ICKDSF maintenance on the M-VOL or to access the R-VOL

(read only mode). TC390 pairs are also suspended when the CGROUP/ RUN command is processed (see

CGROUP (FREEZE/RUN) Support” on page 158

). When the user suspends a TC390 Synchronous pair, the

MCU ensures synchronization by completing any pending update copy operation before changing the

status to suspended. When the user suspends a TC390A pair, the MCU and RCU ensure synchronization

by either completing or discarding any pending update copy operations according to the user-specified

drain/purge suspend option.
A TC390 pair is suspended by the MCU when any of the following suspension conditions are detected. A

TC390A pair can also be suspended by the RCU (see ”

Suspended TrueCopy Asynchronous Pairs

” on

page 40).

When the MCU detects that the user has deleted the volume pair from the RCU (for example, to access

an R-VOL at the remote site).

When the MCU detects an error condition related to the RCU, R-VOL, a TC390 Synchronous update

copy operation or a TC390A recordset operation (see

Suspended TrueCopy Asynchronous Pairs

” on

page 40).

When the RCU cannot execute DFW (DASD fast write) to the R-VOL (only if DFW required is selected).

When the MCU is unable to communicate with the RCU.

Suspended

(see

Table 10 on

page 39

for suspend

types)

This volume pair is not synchronized:
For TC390 Synchronous only, if the MCU cannot keep the pair synchronized for any

reason, the MCU changes the status of the M-VOL and R-VOL (if possible) to suspended.
For TC390A only, if the MCU detects a TC390A suspension condition (see ”

Suspended

TrueCopy Asynchronous Pairs

” on page 40), the MCU changes the M-VOL status and

R-VOL status (if possible) to suspended.
For TC390A only, when the RCU detects a TC390A suspension condition (see ”

Suspended

TrueCopy Asynchronous Pairs

” on page 40), the RCU changes the R-VOL status to

suspended.
For TC390 Synchronous only, the MCU changes the status of all TC390 Synchronous pairs

to suspended when it performs the CGROUP/RUN command (see

CGROUP

(FREEZE/RUN) Support” on page 158

).

When you suspend a pair from the MCU, the MCU changes the status of the M-VOL and

R-VOL (if possible) to suspended. When you suspend a pair from the RCU, the RCU

changes the status of the R-VOL to suspended.
When the MCU detects that the pair was suspended or deleted from the RCU, the MCU

changes the status of the M-VOL to suspended.

Pair Status for TC390A only:

Suspending

This pair is not synchronized. This pair is in transition from duplex or pending duplex to

suspended. When the suspension is requested (by user, MCU, or RCU), the status of all

affected pairs changes to suspending. When the suspension is complete, the status

changes to suspended.

Deleting

This pair is not synchronized. This pair is in transition from duplex, pending duplex, or

suspended to simplex. When the delete pair operation is requested (by user), the status of

all affected pairs changes to deleting. When the delete pair operation is complete, the

status changes to simplex.

SEQCHK

The RCU encountered a non-time-stamped recordset for a TC390A pair using the System

timer type option. This status can be displayed at the MCU and RCU, but the MCU may not

have the most current information. Always use the pair status information displayed at the

RCU for disaster recovery.

Table 9

TrueCopy volume pair status (continued)

Pair Status

Description

Advertising