# Host Monitoring

AOM monitors the resource usage and health status of hosts, common system devices such as disks and file systems of hosts, and service processes or instances running on hosts.

The ICAgent reports resource information every ten minutes. The resource status changes are described as follows:

- If the ICAgent on a host does not report resource information for three consecutive times, the system determines that the resource has been deleted. Therefore, the host status is displayed as Deleted within 30 minutes after the host is stopped or the ICAgent is uninstalled.
- When the ICAgent on a host reports resource information for one time, the system determines that the resource is restored. The host status is displayed as Normal ten minutes after the host is started or the ICAgent is reinstalled.

#### Precautions

- A maximum of five tags can be added to a host, and each tag must be unique.
- The same tag can be added to different hosts.
- For hosts created on the CCE or ServiceStage console, you cannot select clusters or create aliases for them.
- The host status can be Normal, Abnormal, Warning, Silent, or Deleted. The running status of a host is displayed as Abnormal when the host is faulty due to network failures, and power off or shut down of the host, or when the host generates a threshold alarm. If resources are not running properly, follow the instructions in What Can I Do If Resources Are Not Running Properly?.

#### Procedure

1. Log in to the management console.
2. Under Application, click Application Operations Management.
3. In the navigation pane, choose Host Monitoring and perform the following operations as required:

   - Adding an alias

     If a host name is too complex to identify, you can add an alias, which makes it easy to identify a host as required.

     In the host list, choose More > Add Alias in the Operation column of a desired host.

   - Adding a tag

     Tags are identifiers of hosts. You can manage hosts using tags. After a tag is added, you can quickly identify and select a host.

     In the host list, click Add tags in the Operation column of the row that contains the target host. In the displayed dialog box, click , enter a tag, and click and OK. After a tag is added, you can enter a tag keyword in the search box in the upper right corner of the page to search for a host. The Tags column of the host list is hidden by default. You can click in the upper right corner and select or deselect Show tag.

4. Set filter criteria to search for the host to be monitored and monitor resource usage and health status of the host.

   Figure 1 Monitoring the resource usage and health status of the desired host
5. Click the host name to enter the Host Details page. In the instance list, monitor the resource usage and health status of the instances running on the host. Click the View Monitor Graphs tab to monitor all the metrics of the host.

   - Creating a view template

     AOM provides the default view template (Host Template) that you can modify. You can also click the plus sign (+) in to add you own template.

   - Adding a metric graph

     You can click to add a line graph or to add a digit graph to the view template. You can also delete, move, and copy metric graphs in the view template according to Dashboard.

   - Adding a view template to a dashboard

     On the host details page, choose More > Add To Dashboard in the upper right corner to add the view template to a dashboard for monitoring.

6. Monitor common system devices such as GPUs and NICs of the host.

   - Click the GPUs tab to view the basic information about the GPUs of the host. Click a GPU to monitor its metrics on the View Monitor Graphs page.
   - Click the NIC tab to view the basic information about the NICs of the host. Click a NIC to monitor its metrics on the View Monitor Graphs page.
   - Click the Disks tab to view the basic information about the disks of the host. Click a disk to monitor its metrics on the View Monitor Graphs page.
   - Click the File System tab to view the basic information about the file system of the host. Click a disk file partition to monitor its metrics on the View Monitor Graphs page.

Parent topic: Resource Monitoring