Planned outage of the mcu, Planned outage of the mcu and rcu – HP StorageWorks XP Remote Web Console Software User Manual
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generate SIMs reporting the failures. The MCU will change the status of the P-VOLs to suspended-by
RCU but will not be able to change the status of the S-VOLs.
If an MCU/RCU is powered off and its backup batteries are fully discharged while XP Continuous
Access pairs are suspended, the P-VOL/S-VOL differential data will not be retained. In this unlikely
case, the MCU/RCU will mark all tracks of all suspended XP Continuous Access P-VOLs as modified
so that the MCU will perform the equivalent of an entire initial copy operation when the pairs are
resynchronized. The S-VOL differential data is used for XP Continuous Access Asynchronous
operations and for the XP Continuous Access S-VOL write enable option.
Planned Outage of the MCU
A planned MCU outage does not affect XP Continuous Access Synchronous. For XP Continuous
Access Asynchronous operations, the MCU must communicate with the RCU even if there are no
P-VOL update I/Os from the primary system. During the power-off sequence, the MCU automatically
suspends all XP Continuous Access Asynchronous pairs in the PAIR and COPY states (suspend type
= MCU P/S-OFF). During the power-on-reset sequence, the MCU automatically resynchronizes
these suspended pairs (pairs with other suspend types are not automatically resynchronized).
Planned Outage of the RCU or Remote Copy Connection
You must split all affected XP Continuous Access pairs prior to a planned outage of an RCU or of
a remote copy connection component (for example, switch or channel extender). If you do not split
the pairs first, the MCU(s) will detect the communications failure, suspend all affected pairs, and
generate SIMs reporting the failures. To perform a planned outage of an XP Continuous Access
RCU or remote copy connection component:
1.
Identify all XP Continuous Access P-VOLs that will be affected by the equipment outage. You
need to know the MCU, CU, and ID (port, GID, LUN) for each of these P-VOLs.
a.
For an RCU power-off, identify all P-VOLs that are paired with S-VOLs in the RCU to be
powered off.
b.
For a remote copy connection outage, identify all P-VOLs in all MCUs that use the
path/component to be powered off.
2.
Connect to each MCU that contains affected P-VOLs, and split all affected XP Continuous
Access pairs. Make sure to confirm the pair status changes (Pair Operation window or Detailed
Information dialog box).
3.
Perform the planned outage of the RCU or remote copy connection.
4.
When the RCU is fully powered on and ready to resynchronize operations, resynchronize
(pairresync) all XP Continuous Access pairs at each MCU. Make sure to confirm the pair status
changes.
Planned Outage of the MCU and RCU
When you plan an outage of XP Continuous Access MCUs and RCUs at the same time, the MCUs
must be powered off before the RCUs and powered on after the RCUs. To perform a planned
outage of an XP Continuous Access MCU and RCU:
1.
If an RCU power-on will be difficult to control (for example, Power-Control-Interface setting),
you should consider increasing or disabling the Time Out (RCU ready) group option (see
) for each XP Continuous Access Asynchronous group with S-VOLs
in the RCU(s) to be powered off.
2.
Perform the planned outage of the MCU(s) as described in
. Do not power-on the MCU(s) yet.
3.
If an RCU to be powered off is connected to an MCU that is not powered off, make sure to
split those XP Continuous Access pairs before powering off the RCU.
4.
Perform the planned outage of the RCU(s) as described in
Remote Copy Connection” (page 145)
.
Powering Off/On XP Continuous Access Components
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