F5CAB1 Exam Dumps : BIG-IP Administration Install, Initial Configuration, and Upgrade

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 adedicated, 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 allowlist (for HTTPS) and configuration options insshd(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.

The BIG-IPmanagement interface (MGMT port)is controlled throughSystem settings, not through the Network menu.

SSH access on the management interface is configured here:

System → Configuration → Device → General → SSH Access / SSH IP Allow

This section allows the administrator to:

Enable or disable SSH service

Restrict SSH access to specific IP addresses or subnets

Apply security policies to the management interface

Why the other options are incorrect:

A. Network > Interfaces

Used for data-plane physical interface settings, not management plane SSH restrictions.

B. Network > Self IPs

Controls in-band management or data-plane access, not the dedicated management port.

D. System > Platform

Used for hostname, time zone, LCD contrast, hardware settings — not SSH security on the management port.

Therefore, restricting SSH access to themanagement interfacemust be done under:

✔System → Configuration → Device → General

Which corresponds toOption C.

When upgrading to a newer TMOS software version, BIG-IP validates whether the current license is permitted to run that version.

This is controlled by theService Check Datein the device’s license file.

If the Service Check Date is older than the minimum required for the target version:

The systemboots into the new volume,

Butfails to load the configuration,

And will instead present messages indicating that the configuration cannot be applied due to aninvalid or outdated license.

This is a well-known behavior:

An outdated license, not reactivated before upgrade, causes configuration load failure after reboot into the new software.

Why the other options are incorrect:

A. Performed on the standby unit

Upgrading a standby unit does not cause configuration load failure.

Standby-only upgrades are standard best practice.

C. Two reboots required

BIG-IP does not require two reboots during an upgrade.

One reboot into the new volume is sufficient.

D. DNS connectivity failure

DNS connectivity does not affect configuration loading.

DNS is only needed for automatic license activation, not for applying config at boot.

Thus, the configuration failed to load because thelicense was not reactivated before the upgrade, makingOption Bcorrect.