New system functions, Section “new system functions, 7 new system functions – FUJITSU CentricStor V3.1D User Manual
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New system functions
2.7 New system functions
CentricStor Version 3.1C for the first time provides the option of creating logical volumes
(LVs) more than 2 GB in size as a standard feature. The LV size can be selected in discrete
steps for each logical volume group (LVG):
The DTV file system must be migrated for CentricStor systems configured with
Version 3.0 or earlier. This is done by the service staff.
For the user, using large logical volumes is basically no different from the way logical
volumes have been used to date.
The following special aspects must be taken into consideration:
–
The LV size of an existing LVG can be increased if the PVs (physical volumes) of the
PVG (physical volume group) which is linked to the LVG has the necessary capacities
(see the
section “Logical Volume Groups” on page 173
).
–
The LV size of an existing LVG cannot be decreased (see the
).
–
The size of the LVG "TR-LVG" cannot be modified (see the
).
–
An LVG with LVs > 2 GB can be assigned to a PVG only if the capacity of the PVs
already assigned is twice as large as the LV size (see the
Operations » Link/Unlink Volume Groups” on page 221
).
–
PVs can be assigned to a PVG only if their capacity is greater than or equal to the LV
size of the LVG which is linked to the PVG (see the
section “Physical Volume Opera-
tions » Add Physical Volumes” on page 223
).
–
The TVC must be large enough to permit the use of large LVs. If the TVC is too small,
frequent displacement of LVs must be reckoned with. This can have a significant effect
on the LV mount times depending on the volume size and the drive type (e.g. with 200
GB approx. 90-120 min.).
●
STANDARD:
900 MB
●
EXTENDED:
2 GB
5 GB
10 GB
20 GB
50 GB
100 GB
200 GB
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