VIO Volume Groups Test

A physical volume is a collection of regions on one or more disks. Data is stored in physical volumes and administrative operations are performed on physical volumes. A volume group is a collection of one or more physical volumes of varying sizes and types. A physical volume can belong to only one volume group per system; there can be up to 4096 active volume groups on a Virtual I/O Server.

To know the state, composition, and usage of each volume group configured on a Virtual I/O server, use this test.

Target of the test : An IBM pSeries server

Agent deploying the test : A remote agent

Outputs of the test : One set of results for each volume group configured on the VIO server on the IBM pSeries server being monitored.

Configurable parameters for the test
Parameter	Description
Test period	How often should the test be executed
Host	The IP address of the host for which this test is to be configured.
Port	Indicate the port at which the specified Host listens. By default, this is NULL.
HMC Server IP	This test connects to an HMC server to perform LPAR discovery and to collect host-level and "outside view" metrics from the pSeries server. To enable this communication, first, provide the IP address/host name of the HMC server in the HMC Server IP text box. If the eG manager had automatically discovered the target pSeries server by connecting to an HMC server in the environment, then, the IP address/host name will be automatically displayed in the HMC Server IP text box. and user credentials pertaining to that HMC server However, if the pSeries server being monitored was manually added to the eG Enterprise system (and not auto-discovered via the HMC server), then, you will have to explicitly provide the IP address of the HMC server that manages the target pSeries server in the HMC Server IP text box.
HMC Console Username, HMC Console Password and Confirm Password	This test makes REST API requests to the HMC console to pull the metrics. For this purpose, the test needs to be configured with the credentials of a user who can access the HMC console in the HMC Console Username and HMC Console Password text boxes. Confirm the HMC Console Password by retyping it in the Confirm Password text box.

Measurements made by the test
Measurement	Description	Measurement Unit	Interpretation
Volume group status	Indicates the current state of this volume group.	Percent	If this measure reports the value 100, it indicates that this volume group is active/complete. Such a state implies that all physical volumes within the group are currently active. On the other hand, if this measure reports the value 0, it indicates that this volume group is active/partial. This state implies that some physical volumes in the group are currently inactive.
Maximum logical volumes	Indicates the maximum number of logical volumes allowed in this volume group.	Number	A logical volume presents the user with a contiguous address space of pages (0 .. N-1 pages in a volume with N pages) on secondary storage. Page I/O, mounting, and dismounting volumes is performed by applications on logical volumes. A logical volume is mapped to one or more physical volumes. All user I/O occurs through a logical volume.
Currently available logical volumes	Indicates the number of logical volumes currently in this volume group.	Number	The detailed diagnosis of this measure lists the logical volumes within the group, the current state of the volume, and the number of logical partitions, physical partitions, and physical volumes attached to this volume group.
Currently opened logical volumes	Indicates the number of logical volumes within this volume group that are currently open.	Number
Total physical volumes	Indicates the total number of physical volumes within this volume group.	Number	To know which physical volumes are within this group, use the detailed diagnosis of this measure. The detailed diagnosis will list the physical volumes in the group, the state of each volume, the number of physical partitions within every volume, and the number of free partitions per volume.
Stale physical volumes	Indicates the total number of stale physical volumes within this volume group.	Number	A physical volume is stale if its contents reflect a version of the logical volume that is earlier than the current version. Typically, if a user mounts a logical volume while one of two physical volumes backing it is unavailable, but immediately dismounts it, the unavailable physical volume is declared as stale.
Currently active physical volumes	Indicates the number of physical volumes that are currently active in this volume group.	Number
Maximum physical partitions per volume group	Indicates the maximum number of physical partitions allowed for this volume group.	Number
Maximum physical partitions per physical volume	Indicates the maximum number of physical partitions per physical volume allowed for this volume group.	Number
Size of each physical partition	Indicates the size of each physical partition supported by each physical volume in this volume group.	MB	When you add a physical volume to a volume group, the physical volume is partitioned into contiguous, equal-sized units of space called physical partitions. A physical partition is the smallest unit of storage space allocation and is a contiguous space on a physical volume. Physical volumes inherit the volume group’s physical partitions size.
Total physical partitions	Indicates the total number of physical partitions within this volume group.	Number
Not allocated physical partitions	Indicates the number of physical partitions in this volume group that are not allocated to logical volumes.	Number
Allocated physical partitions	Indicates the number of physical partitions in this volume group that are currently allocated to logical volumes.	Number
Stale physical partitions	Indicates the number of stale physical partitions currently available in the logical volumes supported by this volume group.	Number	A STALE physical partition is a physical partition that contains data you cannot use. Physical partitions marked as STALE must be updated to contain the same information as valid physical partitions. This process, called resynchronization, can be done at vary-on time, or can be started anytime the system is running. Until the STALE partitions have been rewritten with valid data, they are not used to satisfy read requests, nor are they written to on write requests.
Maximum physical volumes	Indicates the maximum number of physical volumes allowed in this volume group.	Number

The detailed diagnosis of the Currently available logical volumes measure lists the logical volumes within the group, the current state of the volume, and the number of logical partitions, physical partitions, and physical volumes attached to this volume group.

Figure 1 : The detailed diagnosis of the Currently available logical volumes measure

The detailed diagnosis of the Total physical volumes measure will list the volumes in the group, the state of each volume, the number of physical partitions within every volume, and the number of free partitions per volume.

Figure 2 : The detailed diagnosis of the Total physical volumes measure