Cloudera Manager provides a number of features that let you configure and manage the hosts in your clusters.
The Status Tab
Viewing All Hosts
To display summary information about all the hosts managed by Cloudera Manager, click Hosts in the main navigation bar. The All Hosts page displays with a list of all the hosts managed by Cloudera Manager.
- Clicking the to the left of the number of roles lists all the role instances running on that host. The balloon annotation that appears when you move the cursor over a link indicates the service instance to which the role belongs.
- All columns in the table can be filtered either by typing text and clicking Enter or by selecting a filter specification from the drop-down list in the filter field.
- You can change the data you see for the hosts in the host list using the View Columns menu:
- Current States shows you basic information (Host name, IP, rack assignment, CDH version, health status, when the Last Heartbeat occurred, and the Decommission status.)
- Physical Attributes shows you physical information about the host such as the number of cores, system load averages for the past 1, 5, and 15 minutes, disk usage, physical memory and swap space usage.
Disks OverviewClick the Disks Overview button to display an overview of the status of all disks in the deployment. The statistics exposed match or build on those in iostat, and are shown in a series of histograms that by default cover every physical disk in the system.
Adjust the endpoints of the time line to see the statistics for different time periods. Specify a filter in the box to limit the displayed data. For example, to see the disks for a single rack rack1, set the filter to: logicalPartition = false and rackId = "rack1". Click a histogram to drill down and identify outliers.
Viewing the Hosts in a Cluster
- Select .
- In the Home screen, click in a cluster table.
Viewing Individual Hosts
You can view detailed information about an individual host—resources (CPU/memory/storage) used and available, which processes it is running, details about the host agent, and much more—by clicking a host link on the All Hosts page. See Viewing Host Details.
The Configuration Tab
The Configuration tab lets you set properties related to parcels and to resource management, and also monitoring properties for the hosts under management. The configuration settings you make here will affect all your managed hosts. You can also configure properties for individual hosts from the Host Details page (see Viewing Host Details) which will override the global properties set here).
- Select .
For more information on making configuration changes, see Modifying Configuration Settings.
The Templates Tab
The Templates tab lets you create and manage host templates, which provide a way to specify a set of role configurations that should be applied to a host. This greatly simplifies the process of adding new hosts, because it lets you specify the configuration for multiple roles on a host in a single step, and then (optionally) start all those roles.
The Parcels Tab
In the Parcels tab you can download, distribute, and activate available parcels to your cluster. You can use parcels to add new products to your cluster, or to upgrade products you already have installed.
Other Host Configuration Tasks
The following topics describe other tasks you can perform concerning the hosts on your cluster.