BIG-IP controls access to the web-based Configuration Utility (TMUI) through the/sys httpd allowlist. This parameter specifies which client IPs or subnets may initiate HTTP/HTTPS connections to the management interface.

To restrict TMUI access toonlythe 10.0.0.0/24 subnet:

The correct method is tomodify the HTTPD allow listso that it contains only this subnet.

This requires replacing the entire current list with the new subnet using:

modify /sys httpd allow replace-all-with {10.0.0.0/24}

This ensures thatonlyclients within 10.0.0.0/24 can reach the Configuration Utility.

Why the other options are incorrect:

Options A and Ccreate network ACL objects under /net acl, which apply to data-plane traffic, not management-plane TMUI access. TMUI access is not controlled by LTM ACLs but by the HTTPD allow directive.

Option Bis incorrect syntax and references /ltm httpd, which is not the proper object; the correct hierarchy is /sys httpd.

Thus, only modifying the/sys httpd allowlist achieves the required restriction.