/ Chapter 4. Configuring Cluster Resources with the GUI | ||||
|---|---|---|---|---|
 | Part II. Configuration and Administration | 4.2. Creating Cluster Resources |  | |
/ Chapter 4. Configuring Cluster Resources with the GUI | ||||
|---|---|---|---|---|
| Part II. Configuration and Administration | 4.2. Creating Cluster Resources | | |
Contents
Abstract
The main purpose of an HA cluster is to manage user services. Typical examples of user services are an Apache web server, or a database. From the user's point of view, the services do something specific when ordered to do so. To the cluster, however, they are just resources which may be started or stopped—the nature of the service is irrelevant to the cluster.
As a cluster administrator, you need to create cluster resources for every resource or application you run on servers in your cluster. Cluster resources can include Web sites, e-mail servers, databases, file systems, virtual machines, and any other server-based applications or services you want to make available to users at all times.
To create cluster resources, either use the graphical user interface (the
Linux HA Management Client) or the crm command line utility. For the
command line approach, refer to
Chapter 5, Configuring Cluster Resources From Command Line.
This chapter introduces the Linux HA Management Client and then covers several topics you need when configuring a cluster: creating resources, configuring constraints, specifying failover nodes and failback nodes, configuring resource monitoring, starting or removing resources, configuring resource groups or clone resources, and migrating resources manually.
The graphical user interface for configuring cluster resources is
included in the
pacemaker-pygui package.
When starting the Linux HA Management Client you need to connect to a cluster.
![[Note]](admon/note.png) | Password for the hacluster User |
|---|---|
The installation creates a linux user named
Do this on every node you will connect to with the Linux HA Management Client. | |
To start the Linux HA Management Client, enter crm_gui at the command
line. To connect to the cluster, select +. By
default, the field shows the localhost's IP
address and hacluster as . Enter the user's password to continue.
If you are running the Linux HA Management Client remotely, enter the IP address of a
cluster node as . As , you can also use any other user belonging to the
haclient group to connect ot the cluster.
After being connected, the main window opens:
The Linux HA Management Client lets you add and modify resources, constraints,
configurations etc. It also provides functionalities for managing cluster
components like starting, stopping or migrating resources, cleaning up
resources, or setting nodes to standby. Additionally,
you can easily view, edit, import and export the XML structures of the
CIB by selecting any of the subitems and
selecting +.
In the following, find some examples how to create and manage cluster resources with the Linux HA Management Client.
