Free Practice Questions for the F5-CA F5CAB1 Exam (2026 Updated)

When a TMOS ISO file is transferred to /shared/images/ , the BIG-IP automatically performs a validation step:

Checksum Verification

Before the image becomes visible in the GUI, the system verifies the internal checksum embedded inside the ISO.

This ensures:

The file was fully transferred

The image is not corrupted

It matches the official F5 release signature

Only after passing this verification does the GUI display the ISO under “Available Images.”

Why the other options are incorrect:

A. Reboot into a new partition

No reboot occurs simply from uploading an image.

C. Copying into /var/local/images/

This directory is not used for ISO storage.

All valid images remain in /shared/images/ .

Thus, the correct system action is checksum verification .

Comprehensive and Detailed Explanation From BIG-IP Administration — Install, Initial Configuration, and Upgrade:

When provisioning modules on a BIG-IP system, F5 provides specific resource allocation settings that define how system resources — CPU, memory, and disk — are distributed to each licensed module. The two valid and officially recognised allocation settings are Nominal and Dedicated .

Nominal instructs the system to allocate a moderate, balanced share of resources to the module. It allows the module to function effectively while sharing system resources with other provisioned modules. This is the most commonly used setting in multi-module deployments.

Dedicated allocates the maximum available system resources exclusively to a single module. When this setting is applied, it is typically the only module provisioned, as it consumes resources at a level that prevents other modules from operating concurrently in a meaningful capacity.

Option A — Maximum is not a valid BIG-IP provisioning allocation level; it does not appear in the official provisioning interface or documentation as a selectable resource tier.

Option C — Limited similarly does not exist as a defined resource allocation setting within BIG-IP module provisioning. It may superficially resemble valid terminology but has no standing in the official provisioning framework.

Administrators access these settings via System » Resource Provisioning in the Configuration Utility, where each licensed module displays its available allocation options.

Reference Topics: Module Resource Provisioning, Nominal vs. Dedicated Allocation, System Resource Management — BIG-IP Administration Study Guide.

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 the Service Check Date in the device’s license file.

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

The system boots into the new volume ,

But fails to load the configuration ,

And will instead present messages indicating that the configuration cannot be applied due to an invalid 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 the license was not reactivated before the upgrade , making Option B correct.

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

The BIG-IP has two distinct planes:

Management-plane → handled entirely by the management interface (MGMT)

Data-plane (TMM) → handles Self IPs, VLAN interfaces, and traffic processing

To capture traffic on the management interface, only the management-side NICs may be used:

mgmt → Logical name for the management interface

eth0 → Physical Linux interface mapped to the management port on most BIG-IP platforms

Both of these correctly capture inbound/outbound WebUI (HTTPS/443) traffic on the management port.

Why the correct answers are A and B

A. tcpdump -i eth0 -n port 443

On BIG-IP appliances and VMs, the management port maps to eth0 at the Linux OS level.

Capturing on eth0 correctly shows HTTPS traffic to the WebUI.

B. tcpdump -i mgmt -n port 443

mgmt is the BIG-IP alias for the management interface.

This is the preferred and most explicit capture interface for management-plane packet captures.

Why the other options are incorrect:

C. tcpdump -i 0.0

Interface 0.0 is the TMM switch interface used for data-plane packet captures.

It does NOT capture management-plane traffic.

D. tcpdump -i tun0

Used for tunnel interfaces (IPsec, VXLAN, etc.)

Not related to management access.

E. tcpdump -i management

There is no interface named management on BIG-IP.

The correct names are mgmt or eth0.

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

However, certain traffic types bypass Port Lockdown for BIG-IP functionality and routing integrity.

The three types that are NOT affected by Port Lockdown are:

1. Defined Virtual Server Traffic

Traffic destined to a Self IP that matches a configured virtual server is always accepted by the BIG-IP, regardless of Port Lockdown settings.

This ensures that traffic processing does not break when administrators restrict Self-IP ports.

2. ICMP (Internet Control Message Protocol)

ICMP (such as ping, traceroute responses, etc.) always passes through a Self IP even when Port Lockdown is set to:

Allow Default

Allow None

Allow Custom

F5 allows ICMP for reachability and diagnostic purposes independent of Port Lockdown rules.

3. Centralized Management Infrastructure (CMI)

CMI includes the internal HA services used for:

Device Trust

ConfigSync

Failover

Mirroring

These essential HA communications bypass Port Lockdown to prevent accidental cluster failure.

The well-known port for this traffic is TCP 4353 , which is always permitted.

Why the other options are incorrect:

Option A: SSH is restricted by Port Lockdown unless explicitly allowed.

Option B: Same issue — SSH does not bypass Port Lockdown.

Only Defined VS Traffic , ICMP , and CMI bypass Port Lockdown.

BIG-IP licensing information, including the Service Check Date , is stored in the file:

/config/bigip.license

This file contains all license attributes downloaded from the F5 licensing server, including:

License key

Licensed modules

Useful life date

Service check date

The Service Check Date determines whether the system is eligible for upgrades to specific TMOS versions. When reviewing upgrade readiness, administrators extract this value directly from the license file with:

grep " Service check date " /config/bigip.license

Why the other options are incorrect:

/config/bigip.conf stores BIG-IP configuration objects, not license metadata.

/config/svc_chk_date.dat is not a valid file in the licensing system; it does not contain license parameters.

/config/BigDB.dat stores internal database values, not licensing attributes.

Thus, only the bigip.license file contains the correct licensing information required for verifying upgrade eligibility.

Comprehensive and Detailed Explanation From BIG-IP Administration — Install, Initial Configuration, and Upgrade:

BIG-IP Self IP addresses have an associated Port Lockdown feature that governs which protocols and services are permitted to communicate directly with that Self IP. By default, Self IPs may allow broader access than desired, making Port Lockdown a critical hardening control.

The Allow Custom option under Port Lockdown is the precise mechanism for administrators who need granular, port-specific filtering. When selected, only the explicitly listed TCP/UDP ports are permitted — all others, including port 443 (HTTPS), are implicitly denied. This satisfies the requirement of blocking 443 specifically while preserving access on other required ports.

The remaining options are incorrect for this scenario:

Option A references SSH access control under System » Platform, which governs management-plane SSH — not Self IP service filtering.

Option B disables the entire Self IP, removing all traffic handling, which is operationally disruptive.

Option D — Allow None — blocks all traffic to the Self IP, not selectively port 443.

The Allow Custom approach provides the surgical precision required: administrators enumerate permitted ports, and everything outside that list — including 443 — is dropped.

Reference Topics: Self IP Port Lockdown, Network Security Hardening, Self IP Configuration — BIG-IP Administration Study Guide.

When installing a HotFix on a BIG-IP device, F5 best practices require:

Installing the base TMOS image on a new, unused boot volume (HD1.2)

This ensures the upgrade happens on a clean volume.

The existing active boot location remains untouched for rollback.

Installing the HotFix onto the SAME new boot volume (HD1.2)

HotFixes must be applied on top of a base version.

They cannot be installed on an empty volume.

They must match the base image version.

Activating the new boot volume (HD1.2)

The system reboots into the updated software stack.

Activation happens after base + HotFix installation is complete.

This sequence is exactly shown in Option C :

Install base Image in HD1.2

Install HotFix in HD1.2

Activate HD1.2

Why the other options are incorrect:

A. Install HotFix before base image

Impossible.

HotFix requires an installed base version first.

B. Installing HotFix on HD1.1 (active boot volume)

Not recommended.

Upgrading in-place removes rollback safety.

HotFix cannot be applied cleanly without applying base image first.

D. Activate HD1.2 before installing anything

You cannot activate an empty boot volume.

Activation only occurs after the base + HotFix software is installed.

Within the BIG-IP Traffic Management Shell (tmsh), system configuration objects—including the management IP—are organized under the /sys hierarchy. The management IP address is a configurable property stored in the system configuration and can be viewed using the tmsh list command, which displays configuration objects and their currently assigned values.

Why “list /sys management-ip” is correct

The list command in tmsh is used to display configured system values , not runtime statistics.

The object that holds the management IP settings on BIG-IP systems is located at: /sys management-ip

Running the command: list /sys management-ip will reveal the settings for the management IP interface, including the address, netmask, and any associated attributes.

This is the standard method used during system setup and verification to confirm the management IP configuration.

This behavior aligns with BIG-IP administration procedures, where configuration information is retrieved using list , while operational data is retrieved using show .

Why the other options are incorrect

A. run /util bash ifconfig mgmt

This command enters the Bash shell, then runs ifconfig to display the management interface.

While this can show the management interface address, it is not a tmsh-native command , and the question specifically asks for a tmsh command.

Administrators use tmsh directly for configuration display rather than leaving the shell.

C. show /sys management-ip

The show command displays statistics or operational data , not configuration values.

The management-ip object does not maintain statistics; therefore show does not return the configuration details required.

Only the list command reveals stored configuration data such as IP address and netmask.

Provisioning settings define which modules are enabled and how system resources are allocated to them.

These provisioning declarations are stored in:

/config/bigip.conf

This file contains:

Full module provisioning statements

TMSH-equivalent provisioning configurations such as:

sys provision ltm { level nominal }

sys provision asm { level nominal }

It is the primary system configuration file that stores all active provisioning details.

Why the other answers are incorrect

A. /config/bigip.license

Shows licensed modules, not provisioned modules.

B. /config/bigip_base.conf

Stores base networking (VLANs, Self-IPs, routes), not provisioning.

D. config.ucs

A backup archive, not a live configuration file.

Thus, the correct file to review active module provisioning is /config/bigip.conf .