Securing the BIG-IP management interface is a fundamental administrative responsibility. F5 best practices emphasize restricting who can reach the management port and ensuring that only authorized systems are allowed access.

A. Limiting management access to trusted network segments

F5 recommends placing the management interface on a dedicated, isolated, and secured management network or VLAN , rather than exposing it to production or untrusted networks.

This reduces the attack surface by ensuring only trusted segments have visibility to administrative interfaces.

D. Restricting management access by IP or subnet

F5 BIG-IP uses the /sys httpd allow list (for HTTPS) and configuration options in sshd (for SSH) to control which IP addresses or subnets can access the device.

By specifying only known administrative IPs or ranges, unauthorized users cannot reach the login services.

Why the other options are incorrect

B. Blocking all management HTTPS/SSH ports

This would prevent any administrative access and is not a viable security practice.

C. Using Self-IP addresses for administrative access

F5 explicitly warns against using Self-IPs for management access unless strictly necessary.

Self-IPs are exposed to the data plane and should not be used as the primary administrative interface.