Host Pair Status Reporting For Ca Xp, Bc, And Ca Xp/Bc Shared Vols; Data Currency Of A Shared Continuous Access Xp/Bc Volume - HP StorageWorks XP12000 User Manual

NOTE:
HP recommends Business Copy (BC) intra-disk array copy operations. If BC is not installed, you can
use Continuous Access XP to copy within the same local disk array. This configuration requires at least
one fibre cable loop.
• For shared Continuous Access XP/BC volumes, the Continuous Access XP pair status is reported
to the host if you query the Continuous Access XP 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 CA XP, BC, and CA XP/BC shared vols.
Number of Continuous
Access XP pairs
0
0
0
1
1
1
Table 14 Data currency of a shared Continuous Access XP/BC volume
Continuous BC pair status
Access XP
COPY (PD)
pair status
COPY
Not current
PAIR Not current
Not current
PSUS/PSUE
Figure 12 through Figure 15
Continuous Access XP supports synchronous and asynchronous operations for shared Continuous Access
XP/BC volumes.
• Figure 12 shows an example of a Continuous Access XP P-VOL that also functions as a BC P-VOL.
With this configuration, use BC for on-site data backup if a Continuous Access XP failure occurs,
and use Continuous Access XP to provide remote backup of the BC P-VOL if a BC failure occurs.
46
Continuous Access XP for the Array
Number of BC S-VOLs
0
1
2 or more
0
1
2 or more
PAIR COPY (SP)
Not current Not current
Not current Not current
CURRENT CURRENT
show various Continuous Access XP/BC configurations that share volumes.
Pair status reported by disk array
Simplex
BC pair status
BC pair status for pair whose S-VOL has lowest
LDEV ID
Continuous Access XP pair status
Continuous Access XP pair status
Continuous Access XP pair status
PSUS COPY
(RS/RS-R)
CURRENT Not current
CURRENT Not current
CURRENT CURRENT
PSUE
Not current
Not current
Not current