failgrp command

Purpose

Manages failure groups in a shared storage pool.

Syntax

failgrp -create [-clustername ClusterName] [-sp StoragePool] -fg FGName: PhysicalVolume ...

failgrp -create [-clustername ClusterName] [-sp StoragePool] -file -fg FGName: FileName

failgrp -remove [-clustername ClusterName] [-sp StoragePool] -fg FGName

failgrp -modify [-clustername ClusterName] [-sp StoragePool] [-fg FGName] -attr Attribute=Value

failgrp -list [-clustername ClusterName] [-sp StoragePool] [-verbose | -field FieldName ...] [-fmt delimiter [-header]]

Description

The failgrp command is used to manage the failure groups within a shared storage pool (SSP). A failure group is a set of physical volumes that are treated as a single point of failure by the system, which has one mirror copy of the data in a shared storage pool. By using the failgrp command, various operations, such as create, remove, modify, and list can be performed on the failure groups. When a shared storage pool is created by using the cluster with -create flag, a default failure group is created. A new failure group can be created by using the failgrp with the -create flag. If you create a failure group, it means that it is a second failure group, which has a mirror copy of the data in a default failure group. Ensure that the total capacity of the new failure group that is created is equal to or more than the default failure group. Use -remove flag to remove failure groups from the shared storage pool. This means that one mirror copy of the data is removed. To display information about the failure groups in a shared storage pool, use the -list flag. Use the attr option with -modify flag to modify the specified attribute.

Note: Only two failure groups are supported in a shared storage pool.

Flags

Flag name	Description
-attr	Specifies the failure group attribute and a value to be changed. Supports the following attributes: `fg_name`
-clustername	Specifies the name of the cluster.
-create	Creates the failure group in a shared storage pool.
-fg	Specifies the name of the failure group. When this flag is combined with the -create flag, it specifies the physical volume names, which are separated by a white space or the file name, along with the failure group name.
-file	Specifies that a file name must be provided by using the -create flag. The file must contain physical volume names that are separated by a white space.
-field	Supports one or more of the following fields if the -list flag is specified: `fg_name, fg_size, fg_state, pool_name, tier_name`
-fmt	Separates output that is specific to an individual failure group, by a user-specified delimiter.
-header	Specifies the display field names in the formatted listing output.
-list	Lists failure groups in a shared storage pool.
-modify	Modifies the properties of a failure group.
-remove	Removes failure group from a shared storage pool.
-sp	Specifies name of the shared storage pool.
-verbose	Displays detailed information about the failure group.

Exit Status

This command returns the following exit values:

Return code	Description
0	Successful completion.
>0	An error occurred.

Examples

To create the myfg failure group within the mysp pool. in the mycluster cluster and on two disks hdisk1 and hdisk2, type the following command:
```
failgrp -create -clustername mycluster -sp mysp -fg myfg:hdisk1 hdisk2
```
The system displays the following message:
```
myfg failuregroup has been created successfully.
```
Alternatively, to create the myfg failure group by using the physical volumes from the pvfile file, type the following command:
```
failgrp -create -file -fg myfg:/tmp/pvfile
```
The pvfile file contents: hdisk51 hdisk52

The system displays the following message:
```
myfg failuregroup has been created successfully.
```
To modify the failure group name from myfg to newfg, type the following command:
```
failgrp -modify -fg myfg -attr fg_name=newfg
```
The system displays the following message:
```
Given attribute(s) modified successfully.
```
To list failure groups in a shared storage pool, type the following command:
```
failgrp -list
```
The system displays the following message:
```
POOL_NAME: sp
TIER_NAME: SYSTEM
FG_NAME        FG_SIZE(MB) FG_STATE
Default        20416       ONLINE
```
To remove the newfg failure group from the shared storage pool, type the following command:
```
failgrp -remove -fg newfg
```
The system displays the following message:
```
newfg failuregroup removed successfully.
```

Related Information

The chsp command, cluster command, and lssp command.

Last updated: Wed, November 18, 2020