Agent-based device monitoring in OpManager

Agent monitoring

With the introduction of Agent-based monitoring in OpManager, users can now install a lightweight piece of software called an "agent" in their network devices such as Windows servers to aid OpManager with monitoring your devices. The agent takes over all polling actions related to that device from OpManager, allowing your OpManager server to function more efficiently. For smooth functioning of OpManager without load configuration changes, it is recommended that the agent be installed on not more than 1000 devices.

Agent monitoring feature in OpManager is available in build 125312 and above.

• Advantages of Agent-based monitoring
• Prerequisites for Agent-based monitoring
• Installing the agent in your device

Advantages of Agent-based monitoring

• Credentials are not necessary to employ agent monitoring for your network devices (except when deployed from OpManager UI), it is sufficient if you install the agent in your device.
• Even if communication between the monitored device and OpManager server is lost, the device's monitoring data will be temporarily stored in the agent for upto 6 hours.
• Even if the IP address of the monitored device changes constantly, data collection will not be affected as long as the OpManager server's IP address remains static.

Prerequisites for Agent-based monitoring

Before proceeding to install the agent and beginning to monitor your network devices, there are a few prerequisites that need to be addressed as follows:

1. Hardware requirements
   

   These are the minimum specifications required in the device where the OpManager agent will be installed:

   Parameter	Minimum requirement
   Processor speed	1.0 GHz
   RAM	512 MB
   Hard disk space	100 MB

2. Supported OS versions:
   
   The OpManager agent supports all major versions of Microsoft Windows as listed below:

   • Windows OS:
     • Windows 11
     • Windows 10
     • Windows 8.1
     • Windows 8
     • Windows 7
     • Windows Vista
   • Windows Server OS:
     • Windows Server 2022
     • Windows Server 2019
     • Windows Server 2016
     • Windows Server 2012 R2
     • Windows Server 2012
     • Windows Server 2008
     • Windows Server 2008 R2
3. Port requirements

   To ensure smooth functioning of Agent-based monitoring in OpManager, the following ports need to be opened/available in the firewall, with respect to the device being monitored.

   a. Agent - OpManager server communication

   Port	Protocol	Direction	Description
   OpManager webserver port* (https)	TCP	Outbound	Used for communicating with the OpManager Server to transmit data. (8061 by default)

   b. Remote agent deployment from UI (Deploy Agent)

   For remote deployment, Ports 135 and 445 should be kept open and Inbound with respect to the monitored device. Initially, port 135 is used. RPC later switches it to any random port of TCP Dynamic port range. This dynamic port range must also be opened (Inbound).

   NOTE:

   • These ports might also be needed to set an Outbound rule with respect to the OpManager-Installed device. (OpManager probe-installed device, in case of enterprise edition.)
   • These ports are used only when the Deploy Agent option is used from the OpManager UI.
   • Kindly note that these ports might not be needed post installation. If you do not want to open these ports for deploying the agent remotely, you can use other deployment options.
4. Firewall exceptions for Notification ServerIf Push Mode is going to be enabled in any of the agents, it is necessary that there are no firewall restrictions for the Notification server to run smoothly.
   1. Ensure that WebSocket (WSS) protocol related requests are not blocked in the firewall, for the OpManager server's port (8061 by default, unless changed by the user).
   2. Ensure HTTP 1.1 GET requests are allowed in the firewall.
   3. Ensure Content Length is allowed to be included in the response.
   4. If Path Resolver has been enabled, then the relative path /NSHandler/ needs to be added in the exception list.
   5. All type of Websocket frames (except binary type frame) need to be allowed in the response, if Websocket connection monitor has been enabled.
   6. In your antivirus program, enable WebSocket handling option if has been disabled.
5. Enabling SSL in OpManager

   To start using Agent-based monitoring mode in OpManager, SSL needs to be enabled to ensure secure communication. Click here to read in detail about how you can enable SSL in OpManager.

6. Communication between the device and OpManager server:

   Before beginning the installation process, make sure the OpManager webclient is reachable from the end device that you are going to install the agent in.

7. Adding exclusions in Endpoint Management Solutions:

   If any Endpoint Management solutions have been employed in your network to manage your client computers, these applications need to be added in the exclusion list to ensure the OpManager agent can run without any issues:

   • OpManagerAgent.dll
   • MonitoringAgent.exe
   • MEAgentHelper.exe
   • OpManagerAgentTrayIcon.exe
   • OpManagerTroubleShooter.exe
   • OpManagerAgentUpgrade.exe

Port Usage

The destination Server will also send Ack(Acknowledge) using the same port.

Installing the agent in your device

1. Make sure all the above mentioned prerequisites have been met before beginning the installation.
2. Once done, you can proceed with the agent installation, which can be done in either of these three ways:
   • From OpManager's web console
   • Manual installation
   • Using GPO in Active Directory (bulk installation)
   Once the agent is installed, the device is added into OpManager and is listed under the Inventory page.

1. All default monitors are associated automatically with the help of device templates, based on the device type/category. You can also add additional monitors in the usual methods - from the Device Snapshot page, from Performance Monitors page or from the Device Templates page.
2. You can also view the devices which have the OpManager agent installed in them, by navigating to the Monitoring Agents page under Settings → ITOM Agent → Monitoring Agents. In this page, all the agents are displayed along with the device details and their real-time status.