Pass the F5-CA F5CAB1 Questions and answers with Dumpstech

The BIG-IP system has built-in licensing enforcement.

If an administrator provisions a module that the device isnot licensedto run, the system will still allow the provisioning action to occurinitially, but the system detects the mismatch and displays an alert.

What actually happens:

The GUI places awarning bannerin theupper-left cornerlabeled something similar to:“Provisioning Warning”

This appears immediately after provisioning a module that is not included in the active license.

The system remains in an “inconsistent state” until the module is disabled again or the license is updated.

This is the visual cue BIG-IP uses to indicate that a module was provisioned without valid licensing.

Why the other options are incorrect:

A. “A BIG-IP does not allow unlicensed modules to be provisioned.”

Not true. BIG-IPdoesallow provisioning, but warns afterward.

B. “A warning will appear when provisioning an unlicensed module.”

The warning doesnotappear during the provisioning step itself.

It appearsafter provisioning, in the main GUI, as a system banner.

The exhibit shows theCurrent Resource Allocationfor:

CPU

Disk

Memory

In particular, theMemory Allocationbar displays the modules that are currently provisioned.

Memory is the most reliable indicator because BIG-IP allocates memoryonlyto modules that are actively provisioned.

From the exhibit:

MGMT(Management) – always present

TMM(Traffic Management Microkernel) – indicatesLTM is provisioned

GTM– this label indicates that theDNS moduleis provisioned (GTM = Global Traffic Manager, now called DNS)

APM– explicitly shown, indicatingAccess Policy Manageris provisioned

Therefore, the provisioned modules are:

LTM(implied by TMM allocation)

DNS/GTM

APM

This matchesOption C: LTM, DNS, APM.

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 toeth0at the Linux OS level.

Capturing on eth0 correctly shows HTTPS traffic to the WebUI.

B. tcpdump -i mgmt -n port 443

mgmtis the BIG-IP alias for the management interface.

This is thepreferredand most explicit capture interface for management-plane packet captures.

Why the other options are incorrect:

C. tcpdump -i 0.0

Interface0.0is the TMM switch interface used for data-plane packet captures.

Itdoes NOTcapture management-plane traffic.

D. tcpdump -i tun0

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

Not related to management access.

E. tcpdump -i management

There isnointerface named management on BIG-IP.

The correct names are mgmt or eth0.

Self-IPs include a security feature calledPort Lockdown, which restricts which services respond on that Self-IP.

By default, Self-IPs block management access (SSH and HTTPS/TMUI), meaning an administrator cannot manage the device through in-band Self-IPs unless explicitly allowed.

Allow Mgmt / Allow Management

These settings enable only the management services required for administrative access, specifically:

SSH (22)

HTTPS/TMUI (443)

These options allow secure administration without opening unnecessary ports.

Why these are correct:

They provide only the essential access for management.

They follow F5 security best practices when using in-band admin access.

They donotexpose all services, reducing the attack surface.

Why the other options are incorrect:

A. Allow Default

This allows only a minimal set of system-required ports (e.g., failover, config sync), not SSH or HTTPS.

Administrator access would still fail.

B. Allow All

Opens all ports on the Self-IP, which isnot secure.

Exposes services that should remain restricted.

Therefore,Allow Mgmt / Allow Managementare the correct choices.

BIG-IP licensing information, including theService 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

TheService Check Datedetermines 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.confstores BIG-IP configuration objects, not license metadata.

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

/config/BigDB.datstores internal database values, not licensing attributes.

Thus, only thebigip.licensefile contains the correct licensing information required for verifying upgrade eligibility.

Provisioning determines:

Which BIG-IP modules are enabled (LTM, ASM, APM, AFM, DNS, etc.)

Their provisioning levels (None, Minimal, Nominal, Dedicated)

Two accurate ways to view provisioning settings are:

A. GUI — System → Resource Provisioning → Module Allocation

This is the primary GUI screen showing:

All modules

Their provisioning level

System resource distribution impact

Administrators commonly use this page to confirm or change module provisioning.

D. TMSH — list /sys provision

This tmsh command displays each module and its provisioning level:

sys provision ltm { level nominal }

sys provision asm { level none }

This is the authoritative CLI method for checking module provisioning configurations.

Why the other options are incorrect:

B. show /sys provision

Showsruntimeinformation butnot the actual configuration levels.

list is the correct command for configuration details.

C. Statistics → Module Statistics

Shows performance statistics, NOT provisioning status.

Therefore, the correct responses areAandD.

ThePort Lockdownfeature controls which services a Self-IP will respond to.

Setting a Self-IP toAllow Nonemeans:

The Self-IP will not acceptanytraffic except the very limited, hard-coded HA ports such asTCP 4353used for device trust and configuration sync.

All other HA ports, including those needed for network failover and other HA mechanisms,are blocked.

When essential HA services cannot communicate, each device assumes its peer is down.

This results in:

HA failover misbehavior

Both devices thinking the other is offline

Potentialactive-active condition, which is not intended and can cause traffic disruption

Thus,Allow Nonecan break HA functionality unless the Self-IP is not used for HA links.

To change the boot volume on a BIG-IP system from one installed TMOS version to another, the correct CLI tool is:

switchboot

The correct syntax uses the-bflag:

switchboot -b

This command marks the specified boot location as the one to be used on the next reboot.

Thus, to boot intoHD1.2which contains13.1.0.6, the sequence is:

Mark HD1.2 as the next boot location:

switchboot -b HD1.2

Reboot the system:

reboot

This is the standard and officially supported method for selecting a different installed volume.

Why the other options are incorrect:

A. "tmsh reboot HD1.2"

There is no such tmsh syntax.

Boot volume cannot be selected by adding a parameter to reboot.

C. switchboot -I HD1.2

The -I flag is invalid. Only -b is used.

D. "tmsh switchboot HD1.2"

switchboot isnota tmsh command; it is a system-level shell utility.

Therefore,Option Bis the correct and valid command sequence.

BIG-IP systems require all ISO images (base TMOS images and HotFix images) to be stored in a specific directory used for software installation:

/shared/images/

This directory:

Is theonly supported locationfrom which the BIG-IP software installation system validates and installs ISO files

Is accessible by both the GUI and TMSH installers

Has adequate storage space allocated specifically for images

Is part of the shared partition that persists across reboots

When transferring images via SCP, the administrator must copy them directly into/shared/images/so that:

The GUI (System → Software Management → Available Images) can detect the image

TMSH install software image commands can reference it

Other directories such as/local/images/or/var/images/are not valid storage paths for software images.

The HTTPD allow list controls which IP addresses or subnets may access the Configuration Utility (TMUI) on the BIG-IP system. The Administrator already has two subnets allowed and needs to add asingle host IPto the existing list.

The object/sys httpd allowsupports actions such asadd,delete, andreplace-all-with.

Because the goal is toaddone more entry without removing the existing permitted subnets, the correct command is:

modify /sys httpd allow add { 172.28.32.22 }

This appends the new host to the existing list while preserving the previously configured networks.

Why the other options are incorrect:

Option A (replace-all-with)wouldoverwritethe entire allow list, removing existing permitted subnets—unacceptable.

Option B (delete)wouldremovethe existing networks and not add the required host.

Therefore, the correct administrative action is toaddthe jump host’s IP.