AIX - Quorum - LVCB (Logical Volume control block)

LVCB (Logical Volume control block)

Logical volume control block (LVCB) contains important information about the
Logical volume, such as the number of the logical partitions or disk allocation
Policy. Its architecture and location on the disk depends on the type of the
Volume group it belongs to. For standard volume groups, the LVCB resides on
The first block of user data within the LV. For big volume groups there is
Additional LVCB information in VGDA on the disk. For scalable volume groups
All relevant logical volume control information is kept in the VGDA as part of
The LVCB information area and the LV entry area.


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-- AIX - Quorum - VGDA (Volume Group Descriptor Area)


Volume group descriptor area (VGDA) is an area on the disk that contains
Information pertinent to the volume group that physical volume belongs to. It
Also includes information about properties and status of all physical and
Logical volumes that are part of the volume group. The information from VGDA
is used and updated by LVM commands. There is at least one VGDA per
Physical volume. Information from VGDAs of all disks that are part of the
Same volume group must de identical. VGDA internal architecture and location on the disk depends on the type of the volume group (original, big, or
Scalable).


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-- VGSA (Volume Group Status Area)


Volume group status area (VGSA) is used to describe the state of all physical
Partitions from all physical volumes within a volume group. The VGSA
indicates if a physical partition contains accurate or stale information. VGSA
Is used for monitoring and maintained data copies synchronization. The
VGSA is essentially a bitmap and its architecture and location on the disk
Depends on the type of the volume group.