Hardware Requirements

Enterprise networks can vary in performance, capacity, protocols, and overall activity. Resource requirements to consider for Nessus deployments include raw network speed, the size of the network being monitored, and the configuration of Nessus.

Note: The following recommendations are guidelines for the minimum hardware allocations. Certain types of scans are more resource intensive. If you run complex scans, especially those with credentials, you may require additional disk space, memory, and processing power.

Tip: For information about Tenable Core + Nessus, see Requirements in the Tenable Core User Guide.

Storage Requirements

You must install Nessus on direct-attached storage (DAS) devices. Nessus does not support storage area networks (SANs) or network-attached storage (NAS) configurations.

Tenable recommends a minimum of 1,000 MB of temporary space for the Nessus scanner to run properly.

NIC Requirements

Tenable recommends you configure the following, at minimum, to ensure network interface controller (NIC) compatibility with Nessus:

Disable NIC teaming or assign a single NIC to Nessus.
Disable IPv6 tunneling on the NIC.
Disable packet capture applications that share a NIC with Nessus.
Avoid deploying Nessus in a Docker container that shares a NIC with another Docker container.

For assistance confirming if other aspects of your NIC configuration are compatible with Nessus, contact Tenable Support.

Nessus Scanners and Nessus Professional

The following table lists the hardware requirements for Nessus scanners and Nessus Professional.

Scenario	Minimum Recommended Hardware
Scanning up to 50,000 hosts per scan	CPU: 4 2GHz cores Memory: 4 GB RAM (8 GB RAM recommended) Disk space: 30 GB, not including space used by the host operating system Note: Your usage (e.g., scan results, plugin updates, and logs) increases the amount of disk space needed over time.
Scanning more than 50,000 hosts per scan	CPU: 8 2GHz cores Memory: 8 GB RAM (16 GB RAM recommended) Disk space: 30 GB, not including space used by the host operating system Note: Your usage (e.g., scan results, plugin updates, and logs) increases the amount of disk space needed over time.

Scenario

Minimum Recommended Hardware

Scanning up to 50,000 hosts per scan

CPU: 4 2GHz cores

Memory: 4 GB RAM (8 GB RAM recommended)

Disk space: 30 GB, not including space used by the host operating system

Note: Your usage (e.g., scan results, plugin updates, and logs) increases the amount of disk space needed over time.

Scanning more than 50,000 hosts per scan

CPU: 8 2GHz cores

Memory: 8 GB RAM (16 GB RAM recommended)

Disk space: 30 GB, not including space used by the host operating system

Note: Your usage (e.g., scan results, plugin updates, and logs) increases the amount of disk space needed over time.

Nessus Manager

The following table lists the hardware requirements for Nessus Manager.

Scenario	Minimum Recommended Hardware
Nessus Manager with 0-10,000 agents	CPU: 4 2GHz cores Memory: 16 GB RAM Disk space: 30 GB, not including space used by the host operating system. Note: Scan results and plugin updates require more disk space over time.
Nessus Manager with 10,001-20,000 agents	CPU: 8 2GHz cores Memory: 64 GB RAM Disk space: 30 GB, not including space used by the host operating system. Note: Scan results and plugin updates require more disk space over time. Note: Engage with your Tenable representative for large deployments.

Scenario

Minimum Recommended Hardware

Nessus Manager with 0-10,000 agents

CPU: 4 2GHz cores

Memory: 16 GB RAM

Disk space: 30 GB, not including space used by the host operating system.

Note: Scan results and plugin updates require more disk space over time.

Nessus Manager with 10,001-20,000 agents

CPU: 8 2GHz cores

Memory: 64 GB RAM

Disk space: 30 GB, not including space used by the host operating system.

Note: Scan results and plugin updates require more disk space over time.

Note: Engage with your Tenable representative for large deployments.

Virtual Machine

Nessus can be installed on a Virtual Machine that meets the same requirements. If your virtual machine is using Network Address Translation (NAT) to reach the network, many of the Nessus vulnerability checks, host enumeration, and operating system identification are negatively affected.

Nessus Agents

Nessus Agents are designed to be lightweight and to use only minimal system resources. Generally, a Nessus Agent uses 40 MB of RAM (all pageable). A Nessus Agent uses almost no CPU while idle, but is designed to use up to 100% of CPU when available during jobs.

For more information on Nessus Agent resource usage, see Agent Software Footprint and Agent Host System Utilization.

The following table outlines the minimum recommended hardware for operating a Nessus Agent. Nessus Agents can be installed on a virtual machine that meets the same requirements specified.

Hardware	Minimum Requirement
Processor	1 Dual-core CPU
Processor Speed	> 1 Ghz
RAM	> 1 GB
Disk Space	Agents 7.7.x and earlier: > 1 GB Agents 8.0.x and later: > 3 GB More space may be required during certain processes, such as a plugins-code.db defragmentation operation.
Disk Speed	15-50 IOPS

Note: You can control the priority of the Nessus Agent relative to the priority of other tasks running on the system. For more information see Agent CPU Resource Control in the Nessus Agent Deployment and User Guide.