What Is a Bastion Host?

A bastion host is a secure and hardened server that acts as an intermediary between a client machine and other servers or instances on a private network. The primary function of a bastion host is to provide a secure access point to the private network, allowing authorized users to remotely access and manage the other machines within the network.

A bastion host is typically configured with strong security measures such as two-factor authentication, access control lists, and intrusion detection and prevention systems, to ensure that unauthorized access attempts are prevented. The host can also be configured to log and monitor all activity, providing an audit trail for security and compliance purposes.

In addition to providing remote access, a bastion host can also be used to manage the other machines within the network. For example, system administrators can use the bastion host to deploy updates, patches, and other changes to the network without needing to physically access the machines themselves.

Bastion hosts are often used in cloud environments where access to servers and instances on a private network is required. They are an essential part of network security, as they provide a single, secure entry point to the network, reducing the attack surface and making it easier to monitor and manage access.