6.5 HP StoreAll OS CLI Reference Guide

ibrix_hostgroup
Creates and manages host groups.
Description
A host group is a named set of StoreAll clients. Host groups provide a convenient way to centrally
manage clients. Group-wide procedures include:
• Mounting file systems.
• Preferring or unpreferring a network interface for a host group. You can locally override the
preference on individual StoreAll clients with ibrix_lwhost.
• Tuning host parameters.
• Setting allocation policies.
When ibrix_mount, ibrix_host_tune, or ibrix_fs_tune is executed on a host group,
the command is stored on the Fusion Manager for each StoreAll client until the next time a StoreAll
client contacts it. This happens when the StoreAll client reboots, when StoreAll software services
start on the StoreAll client, or when it is forced to query the Fusion Manager. When contacted, the
Fusion Manager replies to the StoreAll clients with information about commands that have been
executed on host groups to which they belong. The StoreAll clients then use this information to
mount file systems or implement host tunings or allocation policy settings.
To force a query on a StoreAll client, execute ibrix_lwmount -a if you executed ibrix_mount
or ibrix_fs_tune on the host group, or run ibrix_lwhost --a if you executed
ibrix_host_tune.
All StoreAll clients belong to the default clients host group, which can be used to globally mount
file systems, tune hosts, or set allocation policy. To perform different actions on different sets of
StoreAll clients, create additional host groups and assign StoreAll clients to them. This involves
creating a host group tree whose root element is the clients host group. Each host group in a
tree can have exactly one parent, and a parent can have multiple children. To create the first level
of nodes beneath the root, execute ibrix_hostgroup -c -g GROUPNAME. To create subsequent
levels of nodes, execute ibrix_hostgroup -c -g GROUPNAME -p PARENT.
After creating a host group, assign StoreAll clients to it. You can do this manually or have the
Fusion Manager automatically assign the clients when they are registered. To set up automatic
host group assignments, define a domain rule for host groups. A domain rule restricts host group
membership to StoreAll clients on a particular cluster subnet. The Fusion Manager uses the IP
address that you specify for StoreAll clients when you register them to perform a subnet match and
sort the StoreAll clients into host groups based on domain rules. Setting domain rules on host groups
thus provides a convenient way to centrally manage mounting, tuning, and allocation policies on
different subnets of StoreAll clients.
In a host groups tree, operations performed on lower-level nodes take precedence over operations
performed on higher-level nodes. This means that you can effectively establish global StoreAll client
mounts, host tunings, and allocation policies and then override them for specific host groups.
Synopsis
Create a host group tree:
ibrix_hostgroup -c -g GROUPNAME [-D DOMAIN] [-p PARENT]
To create one level of host groups beneath the root clients host group, execute the command
once for every host group that you want to add, but omit the -p PARENT option.
To create additional levels of host groups, execute the command for each host group to be added
and include the -p PARENT option.
To set a domain rule on a host group, include the -D DOMAIN option.
ibrix_hostgroup 107