Free F5 F5CAB1 Practice Exam with Questions & Answers | Set: 2

Port Lockdown controls which ports and protocols a Self IP will respond to.

The Allow Default setting permits only a predefined set of BIG-IP internal and required service ports.

The Allow Default list includes :

TCP 443 → HTTPS (Management/TMUI access via Self-IP)

TCP 4353 → CMI (device sync)

TCP/UDP ports related to HA communication

Other essential internal F5 ports

Why TCP 443 is correct:

It is one of the officially allowed ports under Allow Default .

It enables HTTPS/TMUI access through a Self IP.

Why the other options are incorrect:

A. TCP 80 (HTTP)

Not allowed under Allow Default

HTTP via Self-IP is blocked unless placed under Allow Custom

B. UDP 8443

Not an F5 default service

Not part of the Allow Default ports

BIG-IP allocates CPU and memory resources based on module provisioning levels.

To view how much CPU a module is assigned, administrators must check provisioning information from:

C. GUI — System » Resource Provisioning

This page visually displays CPU allocation via color-coded bars.

Hovering over the CPU bar shows:

CPU usage percent per module

Which modules share CPU cycles

The system’s total resource allocation

This is the primary GUI method.

D. tmsh show /sys provision

This command displays detailed module provisioning information including:

Provisioned modules

Their provisioning level

CPU and memory allocation data

It is the authoritative CLI method for resource provisioning status.

Why the other options are incorrect:

A. top

Shows real-time process usage, not provisioned CPU allocation.

B. tmsh show /sys cpu

Displays CPU runtime utilization, not per-module provisioning.

E. Statistics Dashboard

Only shows traffic / system runtime metrics, not provisioning resource allocations.

Therefore, C and D are correct.

License reactivation updates the BIG-IP device’s license file to ensure:

The Service Check Date is current

The device is eligible to install the intended TMOS version

Any module entitlement updates are received

Reactivation does not interrupt traffic and does not require a reboot, making it safe to perform before the maintenance window.

F5 best practices state:

Perform all non-impact tasks prior to the scheduled maintenance window

Leave the window available for activities that require rebooting, such as the software installation itself

Since license reactivation is non-disruptive , it should be done before the upgrade window starts.

Provisioning defines how BIG-IP allocates system resources to modules. The provisioning levels include:

Dedicated – allocates all CPU, memory, and disk resources to a single module

Nominal – standard resource allocation balanced with other modules

Minimal – lowest level, used for basic utility needs

None – module disabled

Comprehensive / Maximal – not valid TMOS provisioning levels

Why “Dedicated” is correct

When a BIG-IP device is intended to run only ASM (Web Application Firewall), the recommended way to maximize performance is to provision the module at Dedicated level.

With ASM: Dedicated :

ASM receives the entire hardware capacity

No other modules can or should be provisioned

This is explicitly recommended when a device is used solely as a WAF platform

Why other options are incorrect

B. Comprehensive / C. Maximal

These are not valid provisioning modes in BIG-IP.

TMOS supports: Nominal, Minimal, Large (module-specific), and Dedicated.

D. Nominal

Shares resources with other modules

Does not provide full system performance

Not suitable when exclusive resource allocation is required

Thus, Dedicated is the correct provisioning choice.