The Agent Manager component collects data from monitored hosts and sends it to the Management Server. Foglight™ for VMware can monitor host machines remotely. For that reason, the Agent Manager does not need to be installed on each individual host that you want to monitor. The Management Server includes an embedded Agent Manager instance that starts and stops with the server.
One Agent Manager installation per Management Server is often enough, unless additional installations are needed to balance the collection load onto other machines. The minimum supported version of the Agent Manager is 5.8.5.
On 64-bit hosts meeting the minimum system requirements, the embedded Agent Manager can be used to run VMware Performance Agents to monitor up to 500 virtual machines. If the total number of virtual machines to be monitored from a single agent host is greater than 500, an Agent Manager should be installed on a separate host.
1 Additional CPUs may be required for larger environments.
The Agent Manager JVM usually requires additional memory to monitor more than 4000 virtual machines. The total number of virtual machines is the total from all vCenters that will be monitored from all VMware Performance agents running on the Agent Manager.
The following calculations are guidelines, not hard and fast rules. Memory requirements can vary greatly from installation to installation with similar VM counts. If insufficient memory is configured, the failure mode is easily recognizable: all agents on the Agent Manager host will go into a broken state after the agent(s) were activated for a short period of time, usually within 24 hours. In addition, the Agent Manager log will contain a line similar to the following:
Determine the amount of additional memory required. This will be the total from the last step above minus the default value of 2560 MB. In the example above, this is 4608 MB – 2560 MB = 2048 MB.
On the agent machine, open the baseline.jvmargs.config file for editing. The file is located in the <Agent_Manager_home>/state/default/config directory.
Add the following lines to the memory settings section:
When monitoring larger vCenters, the Agent Manager machine hosting the VMware Performance agents should be dedicated to this task. No other Foglight agent types should run on the host and the host should not run any other applications.
Regardless of the values set for JVM memory above, Agent Manager never allocates more than 80% of system memory. So the machine hosting the Agent Manager and VMware Performance Agents must have sufficient memory. Beyond the memory requirements of the Agent Manager, a minimum of 2 GB should be free for the operating system. In the example above for 8000 VMs and an Agent Manager memory requirement of 4608 MB, the host should have a minimum of 6656 MB - the greater of:
CPU usage on the Agent Manager host is relatively low most of the time. However, usage peaks dramatically during the performance metric collection. This is normal and expected. CPU utilization consistently over 50% is an indication that additional processing power is required. As with memory, usage can vary between different installations with similar numbers of virtual machines. The following guidelines should be followed.
When the Agent Manager and VMware Performance agents are running on a virtual machine, the VM should be configured with CPU reservation whenever possible to ensure best performance. Lack of processing power on the Agent Manager manifests in missed collections and gaps in the data usually noticeable in various graphs throughout the Foglight for VMware dashboards.
Foglight™ for VMware supports VMware® vSphere® and VMware vCenter® Server versions 5.0 and later. Foglight for VMware also provides basic monitoring support for vCenter 6.0, but some advanced vCenter 6.0 features such as long distance vMotion® (Cross vCenter vMotion) will not be fully supported until a future release of Foglight for VMware.
Installing Foglight™ for VMware involves several tasks.
First, install Foglight for VMware, and the Agent Manager (if multiple instances are required) and configure the remote host to allow the collection of data. Next, install Foglight for VMware on the Management Server and deploy the agent package. As the final step, you create agent instances, configure their properties, activate them, and start their data collection. For details, see the following :