Event Agent Settings

The Event Agent Settings page is used to make modifications to the agent task characteristics.

This includes the CPU, Memory and Disk Size (for the AWS Fargate tasks), the VPC and Subnet(s) as well as the scaling characteristics including Scaling Threshold, Minimum # of Agents and Maximum # of Agents. This is typically used to make modifications to existing running infrastructure, but this page can also be used to stage regions in anticipation they will be used. This is useful so not just any user picks the VPCs and Subnets to use, but also to pre-configure regions that may be leveraged with tag triggered bucket protection. You also gain a bit of insight into your overall deployment as each region where scanning agents exist is displayed for Event Agents. You can get more detailed deployment info on the Deployment Overview page.

Deployed Agents

Displayed to you are any regions where event agents have been deployed. The Event Agents will be one of two colors, green or orange. Green indicates the agents in those regions are running off the default settings. Whereas orange indicates the agents in those regions are running with custom characteristics. This may occur for many reasons, but one simple example is adapting regions for the load they see. US-East-1 may see the brunt of your object handling and so you tune the scaling and up the Max Agents, whereas your other regions see much less traffic so you turn on Smart Scan for those regions.

To see or manage a specific region's settings, click the pill for the desired region. The pill will fill-in to represent what you are looking at. In the image below, the eu-west-1 region is selected.

This does not indicate whether the agents are running or whether any buckets in those regions are being protected. It does indicate that buckets in those given regions were scanned at one point and the agent has been deployed there.

Staged Regions

The Regions with Event Agents (deployed agents as described above) represent regions that have event agent infrastructure in place. The Staged Regions represent the default settings for all new regions that come online, but also pre-defined regions. Pre-defined regions do not have infrastructure installed, but allow you to pre-define which networking should be used in those regions. Two primary use cases stand out: automatic bucket protection and allowing admins to determine the network to be used rather than the other users of the system. Automatic bucket protection turns event-based protection on for buckets as they are created or have tags added to them. This could be in any region and may happen in regions that are not already protecting buckets and are therefore not setup. Now you can create the setup ahead of time.

Adding a Staged Region will not deploy infrastructure to those regions. It only saves the config details to a database table to be used in the event the region is needed.

To stage a region:

The rest of the settings will be pre-populated from the default settings. You are welcome to keep those or make changes as you see fit.

To learn more about the settings continue reading.

Agent Task Settings

The Task Settings apply to the actual AWS Fargate Task (container) running the scanning agents. The default settings within the CloudFormation Template are to run the agents with 1vCPU and 3GB of Memory. This is suitable for all use cases and file types at this time. You also set the values for Scaling Threshold, Min Agents and Max Agents during the CloudFormation Stack creation. Whether you've determined you need to tune regions or reset all regions to new defaults, this section is to allow you to easily modify the running values of each of the scanning agents.

When you first enable a bucket for protection you are prompted to select a VPC and two Subnets to run the agents in for that region. There may be times you want to change these values after the fact which can easily be done on this page.


Select Region

Click the region pill in the Regions with Event Agents area above. The filled in pill is the currently selected field

Scaling Threshold

This is the value that determines the number of entries in the work queue before a scaling event happens. There are a number of considerations here that can affect what this value should be. Review the Sizing Discussion to get more details on how to think through this

Min Agents

The minimum number of scanning agents you'd like running by default or in the given region. This value can be 0. The scanning agents will not be running, but will scale up based on the Scaling Threshold setting

Max Agents

The maximum number of scanning agents you would like to possibly scale to. This number can be anything greater or equal to the minimum (except 0).


The amount of vCPU you would like allocated to each agent. Each additional auto-scaled agent would also have this value.


The amount of memory you would like allocated to each agent. Each additional auto-scaled agent would also have this value.

Disk Size (GB)

The amount of disk space assigned to each agent. Each additional auto-scaled agent would also have this value. The default value and included in the AWS pricing is 20GB. If all files you will be scanning are under 15GB in size then keep the default. If there are regions or needs to scan files larger than 15GB in size, then increase this to a size larger enough to handle your largest files. 200GB is the current maximum this number can be set to. As a result, the maximum size file that can be scanned through this scanning method is 195GB. If you require the scanning of anything larger than 195GB, please refer to ==Extra Large File Scanning== option. You can scan TB(s) sized files. NOTE: There are increased pricing costs for any GB above the 20GB size. Currently, this price per GB per hour is $0.000111, but refer to the AWS Fargate Pricing page to get the latest costs.

Agent Memory

The Memory must always be set to a value that is between 2x and 8x of the vCPU. The new minimum memory requirement for agents is 3GB.


    vCPU = 1, then 3gb <= memValue <= 8gb  
    vCPU = 2, then 4gb <= memValue <= 16gb
    vCPU = 3, then 6gb <= memValue <= 24gb
    vCPU = 4, then 8gb <= memValue <= 32gb

You'll notice a Public or Private associated with each VPC. This is an indicator of whether or not the VPC is tied to an Internet Gateway. Thought process being that with an IG in place you will have the required outbound access. The console does not require a public IP address or to be accessible from the public in general, but it does require outbound internet access to get to AWS ECR to pull new Task images.

You'll notice a Public or Restricted associated with each Subnet. This is an indicator of whether or not the Subnet is outbound routable to the internet. Minimally, the agent task must be able to reach the AWS ECR to pull new Task images and to be able to pull AV signature updates. Two validations are performed for this check. First, we check to see if the NACL associated with the Subnet(s) has outbound open for Secondly, we check to see if there is a custom Route Table in place and verify it is routed to an internet gateway.

Generally, the first indicator for a good configuration will be whether or not the VPC has an internet gateway or something that is taking its place. Secondly, check the subnets for their outbound access.

Changing these values will cause the agents to reboot.

If the VPC or Subnets are not proper for the agents, you could have trouble with the agents not booting up or entering a constant reboot cycle.

Smart Scan

Smart Scan is an agent settings configuration that creates infrastructure cost optimizations. The idea behind it was to enable and support the scenario where you didn't want or need a scanning agent running full time in one or all of the regions you were protecting.

This is the classic example of run the "server" only when you need it and taking advantage of scaling policies to do just that. Smart Scan can be enabled as the global Default so each and every region you protect is setup that way or on a one-off basis for each region that requires it.

Examples of when Smart Scan is useful

  • You only get new objects during the work day hours and nothing comes in at night. You can switch Smart Scan on and your scanning agents will only run while work is coming in. They may even shut down during stagnant times during the work day as well to add additional savings.

  • Another scenario is where you may have one or two really busy regions and would like to have scanning agents running full time, but in other less used regions you want to take advantage of the scan on-demand settings.


Scaling Threshold

We set this value to 1 by default which states: any time there is work (at least 1 item in the queue) an agent will be spun up to process that work. While it is up if other work comes in it will continue to run and process all of the items in the queue. You can set this value to something greater than 1. For example, you don't want a scanning agent to spin up and process the workload until you have a certain amount of work so you set this threshold to 50 or 100. This would indicate you will scan once you have 50 or 100 objects waiting. This value translates to the LargeQueue CloudWatch Alarm which controls when to spin up scanning agents.

Min Agents

This value is set to 0 which indicates that the agents can contract back down all the way to no running agents.

Max Agents

This value is set to 1, but can be modified to anything greater than 1 as well. This indicates how many agents you would permit to spin up. If you get objects in large sets, it may be useful to have this greater than 1.

SmallQueue CloudWatch Alarm

This attribute is not visible on the page. The value for the CloudWatch Alarm that controls the scale down of the tasks will be set to 1. Meaning, whenever the queue is emptied and below 1 to stop by scaling down all tasks. Note: If you were to simply change the Min Agents to 0 on this page, it would not change this alarm setting. It would still accomplish a shutdown of all agents, but might have unexpected consequences depending on your Scaling Threshold settings.

Turning off Smart Scan will allow you to go back to modifying all the fields. It also goes back to the default scaling up and down behaviors where both the LargeQueue and SmallQueue scaling threshold are set to the same value which is the Scaling Threshold value as you have defined in this page.

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