I introduced Volume Groups in one of my previous posts. In this post I’m going to discuss, how to carry out common operations on Volume Groups. For more information you can see the previous article: Aix Logical Volume Manager A Brief Introduction.
Here are few things which I’m gonna discuss in this post:
How To List Volume Groups
Using command lsvg provides the complete list of Volume Groups available in the system. That does not matter whether the volume group is varied on or varied off.
How To List Only Varied On Volume Groups
Using command lsvg, with -o option provides the list of Volume Groups which are currently varied on. Varied on means the Volume Group is open for use.
wiw_labs:$ lsvg -o
How To List Volume Group Characteristics
To list characteristics of a particular Volume Group, we use the lsvg command with -l option and name of Volume Group.
e.g wiw_labs:$ lsvg appvg
|VOLUME GROUP||appvg||VG IDENTIFIER||005ab34300004c00000000ff753cd62b|
|VG STATE||active||PP SIZE||64 megabyte(s)|
|VG PERMISSION||read/write||TOTAL PPs||1618 (103552 megabytes)|
|MAX LVs||256||FREE PPs||215 (13760 megabytes)|
|LVs||25||USED PPs||1403 (89792 megabytes)|
|OPEN LVs||25||QUORUM||1 (Disabled)|
|TOTAL PVs||2||VG DESCRIPTORS||3|
|STALE PVs||0||STALE PPs||0|
|ACTIVE PVs||2||AUTO ON||yes|
|MAX PPs per VG||32512||Â||Â|
|MAX PPs per PV||2032||MAX PVs||16|
|LTG size||128 kilobyte(s)||AUTO SYNC||no|
|HOT SPARE||no||BB POLICY||relocatable|
Below is explained the meaning of various terms used in the listing:
- Volume Group: Name of Volume Group.
- VG State: active/partial. Partial indicates that some of the Physical Volumes in the Volume Group are not active. See this for more on VG state.
- VG Permission: It indicates if the volume group is read-only or read-write.
- Max LVs: Maximum number of Logical Volumes allowed in Volume Group.
- LVs: Total number of Logical Volumes at present in Volume Group.
- Open LVs: Number of LVs open at present in the Volume Group for any Read Write operation.
- Total PVs: Total number of Physical Volumes present in Volume Group.
- Stale PVs: How many stale Physical Volumes are there in Volume Group. The stale Physical Volumes are those ones on which I/O operations are not possible.
- Active PVs: Total number of Physical Volumes which are active in Volume Group.
- Max PPs per VG: Maximum no. of Physical Partitions which can be there in the Volume Group.
- Max PPs per PV: Maximum number of Physical Partitions which can be there in Physical Volume.
- VG Identifier: The very long string to identify Volume Group.
- PP Size: The size of Physical Partition used in every Physical Volume of Volume Group.
- Total PPs: Total number of Physical Partitions in Volume Group.
- Free PPs: Total number of free Physical Partitions with in Volume Group.
- Used PPs: Total number of Physical Partitions in use in Volume Group.
- Quorum: Whether the quorum is on or not in Volume Group.
- VG Descriptors: Number of Volume Group Descriptor Areas(VGDA) in Volume Group.
- Stale PPs: How many Physical Partitions are stale or unable to perform I/O operations.
- Auto On: Whether the Volume Group will varyon on system startup or not.
- Max PVs: Maximum number of Physical Volumes allowed in this Volume Group.
- Auto Sync: Whether this Volume Group should sync automatically or not.
- BB Policy: Its bad block relocation policy. So, this value here is relocatable, that means we are allowed to relocate bad blocks in this Volume Group if need be.
(Refer AIX Manpages for more details.)