HP StorageWorks XP Remote Web Console Software - Manual (Page 43)

NOTE: HP recommends XP Business Copy (BC) for intra-disk array copy operations. If BC is not
installed, you can use XP Continuous Access to copy within the same local disk array. This
configuration requires at least one fibre cable loop.
•
For shared XP Continuous Access/XP Business Copy volumes, the XP Continuous Access pair
status is reported to the host if you query the XP Continuous Access P-VOL or S-VOL. To obtain
the BC pair status, query the P-VOL of the BC pair.
•
BC supports multiple S-VOLs for each P-VOL. If you issue a pair status query to a BC P-VOL
(for example, pairdisplay), the status for only one BC pair is reported (pair with the S-VOL
with lowest LDEV ID). To obtain the pair status for BC pairs with other S-VOLs, direct the host
query to the specific S-VOL using the S-VOL's LDEV ID in the host command. The BC remote
console software displays the LDEV ID and BC pair status of all S-VOLs associated with a
P-VOL.
Table 13 Host pair status reporting for XP Continuous Access/XP Business Copy shared volumes
Pair status reported by disk array Number of BC S-VOLs Number of XP Continuous
Access pairs
Simplex 0 0
BC pair status 1 0
BC pair status for pair whose S-VOL has lowest LDEV
ID 2 or more 0
XP Continuous Access pair status 0 1
XP Continuous Access pair status 1 1
XP Continuous Access pair status 2 or more 1
Table 14 Data currency of a shared XP Continuous Access/XP Business Copy volume
BC pair status XP Continuous
Access pair
status
PSUE COPY
(RS/RS-R) PSUS COPY (SP) PAIR COPY (PD)
Not current Not current CURRENT Not current Not current Not current COPY
Not current Not current CURRENT Not current Not current Not current PAIR
Not current CURRENT CURRENT CURRENT CURRENT Not current PSUS/PSUE
Figure 14 (page 44) through Figure 17 (page 45) show various XP Continuous Access/XP Business
Copy configurations that share volumes. XP Continuous Access supports synchronous and
asynchronous operations for shared XP Continuous Access/BC volumes.
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Figure 14 (page 44) shows an example of an XP Continuous Access P-VOL that also functions
as a BC P-VOL. With this configuration, use BC for on-site data backup if an XP Continuous
Access failure occurs, and use XP Continuous Access to provide remote backup of the BC
P-VOL if a BC failure occurs.
Combining XP Continuous Access with other data management operations 43