Devices

By clicking on a device name, you can view all of the information discovered about the device by the ExtraHop system on the Device Overview page. The Device Overview page is divided into three sections: a top-level summary, a properties panel, and an activity panel.

https://example-eda/extrahop/#/metrics/devices//0026b94c03810000/overview/&tab=detections

Metrics are real-time measurements of your network traffic that the ExtraHop system calculates from network or flow data. Metrics collected from device traffic can be viewed in built-in charts and graphs from a device page.

Click a built-in metric page from the left pane to view top-level device metrics or client and server metrics by protocol. Click a chart to drill down to detail metric pages, which display metric values for a specific key (such as a client or server IP address).

In addition to network and TCP built-in pages, devices display built-in metric pages for associated cloud services if data is available. See the Protocol Metrics Reference for more information about what data is available on built-in device pages.

The ExtraHop system provides thousands of built-in metrics. Here are some ways you can gain further insight about your devices

• Create a chart to visualize specific metrics and save the chart to a dashboard.
• Create an activity map to view peer device relationships over specified protocols.
• Write a trigger to create custom metrics or create an application container to collect metrics for specific devices.

Type an IP address in the global search field or click an IP address link from a Device Overview page to view details about an IP address.

The following information appears for an IP address seen on a device:

• Each device where the IP address is currently observed, regardless of the selected time interval.
• Each device where the IP address was previously observed within the selected time interval, including the timestamp from when the IP address was last seen on the device.

If L2 Discovery is enabled, both IPv4 and IPv6 addresses might be simultaneously observed on the device, or different IP addresses might be assigned to the device by DHCP over time.

The following information appears for an IP address associated with a device:

• The geolocation of the IP address and links to the ARIN Whois website.
• Each device where the associated IP address was seen outside of the network at any time during the selected time interval. For example, a VPN client on your network might be associated with an external IP address on the public internet.
• Any cloud services associated with the IP address.
• The IP address of the device as seen by the ExtraHop system on your network.
• The timestamp when the associated IP address was last seen on the device.

Here are some ways you can view additional IP address and device information:

• Hover over a device name to view device properties.
• Click a device name to view the Device Overview page.
• Click Search for Records to start a record query that is filtered by the IP .
• Click Search for Packets to start a packet query that is filtered by this device.

Custom devices enable you to collect metrics for devices that are outside of your local network or when you have a group of devices that you want to aggregate metrics for as a single device. These devices can even be different physical interfaces that are located on the same device; aggregating the metrics for these interfaces can make it easier to understand how heavily taxed your physical resources are as a whole, rather than by interface.

You might create a custom device to track individual devices outside of your local broadcast domain or to collect metrics about several known IP addresses or CIDR blocks from a remote site or cloud service. You can collect remote site metrics for custom devices to learn how remote locations consume services and to gain visibility into traffic between remote sites and a data center. See the Protocol Metrics Reference for a full list of remote site metrics and descriptions.

After you create a custom device, all of the metrics associated with the IP addresses and ports are aggregated into a single device that collects L2-L7 metrics. A single custom device counts as one device towards your licensed capacity for Advanced Analysis or Standard Analysis, which enables you to add a custom device to the watchlist. Any triggers or alerts are also assigned to the custom device as a single device.

While custom devices aggregate metrics based on their defined criteria, the metric calculations are not treated the same as for discovered devices. For example, you might have a trigger assigned to a custom device that commits records to a recordstore. However, the custom device is not shown as either a client or a server in any transaction records. The ExtraHop system populates those attributes with the device that corresponds to the conversation on the wire data.

Custom devices can affect the overall system performance, so you should avoid the following configurations:

• Avoid creating multiple custom devices for the same IP addresses or ports. Custom devices that are configured with overlapping criteria might degrade system performance.
• Avoid creating a custom device for a broad range of IP addresses or ports, which might degrade system performance.

If a large number of custom devices is affecting your system performance, you can delete or disable a custom device. The unique Discovery ID for the custom device always remains in the system. See Create a custom device to monitor remote office traffic to familiarize yourself with custom devices.

A device group is a user-defined collection that can help you track metrics across multiple devices that are typically grouped by shared attributes such as protocol activity.

You can create a static device group that requires you to manually add or remove a device from the group. Or, you can create a dynamic device group that includes criteria that determines which devices are automatically included in the group. For example, you can create a dynamic device group based on the device discovery time that adds devices that are discovered during a specific time interval.

By default, the Device Group page includes the following dynamic device groups that you can overwrite or delete:

New Devices (Last 24 Hours)

Includes assets and endpoints that were first seen by the ExtraHop system over the last 24 hours.

New Devices (Last 7 Days)

Includes assets and endpoints that were first seen by the ExtraHop system over the last 7 days.

The ExtraHop system also includes built-in dynamic device groups by role and by protocol. You can assign built-in device groups as a metric source for objects such as charts, alerts, triggers, and activity maps. You cannot overwrite or delete a built-in device group, but you can add filter criteria and save it as a new device group.

From the Devices page, click a device count for a role or protocol, such as Domain Controller or SMB clients, to view the Device Group Overview page. Clicking the filter at the top of the page enables you to add additional criteria and update the page data on demand instead of requiring you to create a device group.

There is no performance impact to collecting metrics with device groups. However, we recommend that you prioritize these groups by their importance to make sure that the right devices receive the highest level of analysis.

Device groups are a good choice when you have devices that you want to collectively apply as a source. For example, you could collect and display metrics for all of your high-priority production web servers in a dashboard.

By creating a device group, you can manage all of those devices as a single metric source instead of adding them to your charts as individual sources. However, note that any assigned triggers or alerts are assigned to each group member (or individual device).

The ExtraHop system discovers device names by passively monitoring naming protocols, including DNS, DHCP, NETBIOS, and Cisco Discovery Protocol (CDP).

If a name is not discovered through a naming protocol, the default name is derived from device attributes, such as MAC addresses and IP addresses. For some devices discovered on flow sensors, the ExtraHop system assigns names based on the role of the device such as Internet Gateway or Amazon DNS Server. You can also create a custom name or set a cloud instance name for a device.

A device can be identified by multiple names, which appear as Known Aliases on the Device Overview page. If a device has multiple names, the order of display precedence is specified in Administration settings. You can search by any name to find a device.

If a device name does not include a hostname, the ExtraHop system has not yet observed naming protocol traffic associated with that device. The ExtraHop system does not perform DNS lookups for device names.

Based on the type of traffic associated with the device or the device model, the ExtraHop system automatically assigns a role to the device, such as a gateway, file server, database, or load balancer. The Other role gets assigned to devices that cannot be identified.

A device can only be assigned one role at a time. You can manually change a device role, or the ExtraHop system might re-assign a different role if observed traffic and behavior changes. For example, if a PC has been repurposed into a Web server, you might change the role immediately, or the change might be observed over time and the role updated by the system.

The ExtraHop system identifies the following roles:

Icon	Role	Description
	Custom Device	A user-created device that collects metrics based on specified criteria. The ExtraHop system automatically assigns this role when you create a custom device. You cannot manually assign the Custom role to a device.
	Attack Simulator	A device that runs breach and attack simulation (BAS) software to simulate attacks in a network.
	Database	A device that primarily hosts a database instance.
	DHCP Server	A device that primarily processes DHCP server activity.
	DNS Server	A device that primarily processes DNS server activity.
	Domain Controller	A device that acts as a domain controller for Kerberos, SMB, and MSRPC server activity.
	File Server	A device that responds to read and write requests for files over NFS and SMB protocols.
	Firewall	A device that monitors incoming and outgoing network traffic and blocks traffic according to security rules. The ExtraHop system does not automatically assign this role to devices.
	Gateway	A device that acts as a router or gateway. The ExtraHop system looks for devices associated with a large amount of unique IP addresses (past a certain threshold) when identifying gateways. Gateway device names include the router name such as Cisco B1B500. Unlike other L2 parent devices, you can add a gateway device to the watchlist for Advanced Analysis.
	IP Camera	A device that sends image and video data through the network. The ExtraHop system assigns this role based on the device model.
	Load Balancer	A device that acts as a reverse proxy for distributing traffic across multiple servers.
	Medical Device	A device designed for healthcare needs and medical environments. The ExtraHop system might assign this role if a device is a known medical make and model or if the device processes DICOM traffic.
	Mobile Device	A device that has a mobile operating system installed, such as iOS or Android.
	NAT Gateway	A device that acts as a Network Address Translation (NAT) gateway. The ExtraHop system might assign this role if a device is associated with four or more OS fingerprint families or with four or more hardware or vendor makes and models. After a device is assigned this role, device properties for software, hardware make and model, and authenticated users no longer appear for the device.
	PC	A device such as a laptop, desktop, Windows VM, or macOS device that processes DNS, HTTP, and TLS client traffic.
	Printer	A device that enables users to print text and graphics from other connected devices. The ExtraHop system assigns this role based on the device model or on traffic observed over mDNS (multicast DNS).
	VoIP Phone	A device that manages voice over IP (VoIP) phone calls.
	VPN Client	An internal device that communicates with a remote IP address. If VPN client discovery is enabled, the ExtraHop system automatically assigns this role to internal devices communicating with remote IP addresses through a VPN gateway. You cannot manually assign the VPN Client role to a device.
	VPN Gateway	A device that connects two or more VPN devices or networks together to bridge remote connections. The ExtraHop system assigns this role to devices with a large number of external VPN peers if automatic classification for this role is enabled in the running configuration file.
	Vulnerability Scanner	A device that runs vulnerability scanner programs.
	Web Proxy Server	A device that processes HTTP requests between a device and another server.
	Web Server	A device that primarily hosts web resources and responds to HTTP requests.
	Wi-Fi Access Point	A device that creates a wireless local area network and projects a wireless network signal to a designated area. The ExtraHop system assigns this role based on the device model.