F5CAB1 BIG-IP Administration Install, Initial Configuration, and Upgrade Questions and Answers

The Port Lockdown feature controls which services a Self-IP will respond to.

Setting a Self-IP to Allow None means:

The Self-IP will not accept any traffic except the very limited, hard-coded HA ports such as TCP 4353 used 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

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

Thus, Allow None can break HA functionality unless the Self-IP is not used for HA links.

To identify which boot volume is currently active on a BIG-IP system, the correct command is:

tmsh show sys software status

This command displays:

All installed boot volumes (HD1.1, HD1.2, HD1.3, etc.)

The BIG-IP software version installed on each volume

The Active field, indicating which volume the system is currently booted from

The installation status (“complete”, “in-progress”, “allowed”)

This is the standard and authoritative way to determine the active boot location.

Why the other options are incorrect:

A. tmsh show sys version

Displays OS version, build, and date.

Does not show boot locations or which volume is active.

C. tmsh list sys software update

Shows software update configurations, not boot volume status.

Does not display which volume is active.

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

The Service Check Date embedded in the BIG-IP license acts as a gating mechanism that determines eligibility for software updates. F5 enforces that the Service Check Date must be equal to or newer than the software release date of any BIG-IP version being installed. If the installed license carries a Service Check Date from two years ago, attempting to upgrade to a newly released BIG-IP software version — whose release date post-dates that Service Check Date — will fail, as the system validates this date during the upgrade process.

Option A is incorrect — generating and uploading a QkView to F5 iHealth is a diagnostic activity that requires no license validation or Service Check Date verification whatsoever.

Option C is incorrect — ASM signature and threat campaign updates are content updates, not platform software upgrades. These updates are independent of the Service Check Date requirement and do not trigger license validation checks during installation.

Only a platform software upgrade to a newly released BIG-IP version directly invokes the Service Check Date validation, mandating license renewal prior to the upgrade proceeding successfully.

Reference Topics: License Service Check Date, Software Upgrade Prerequisites, License Reactivation — BIG-IP Administration Study Guide.

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 exhibit shows the Current Resource Allocation for:

CPU

Disk

Memory

In particular, the Memory Allocation bar displays the modules that are currently provisioned.

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

From the exhibit:

MGMT (Management) – always present

TMM (Traffic Management Microkernel) – indicates LTM is provisioned

GTM – this label indicates that the DNS module is provisioned (GTM = Global Traffic Manager, now called DNS)

APM – explicitly shown, indicating Access Policy Manager is provisioned

Therefore, the provisioned modules are:

LTM (implied by TMM allocation)

DNS/GTM

APM

This matches Option C: LTM, DNS, APM .

In BIG-IP, software images are installed on boot volumes (for example, HD1.1, HD1.2, HD1.3, etc.).

To install software on a new volume , the administrator must instruct the system to create a new boot location before installation.

There are two correct ways to create a new volume:

A. tmsh command (with correct syntax)

tmsh install software image /shared/images/BIGIP- < version > .iso volume HD1.5 create-volume

This syntax correctly includes:

install software image

full path to ISO (/shared/images/...)

volume name (HD1.5)

create-volume keyword

This instructs BIG-IP to create the new boot volume as part of the installation.

C. Using the GUI → System > Disk Management

From the Disk Management menu, the administrator can:

Select “New Volume”

Enter the volume identifier (e.g., HD1.5)

Apply changes

This GUI method is officially supported and explicitly creates a new boot volume before installing the software.

Why the other options are incorrect:

B. Incorrect tmsh syntax

Missing /shared/images/ path

Incorrect command structure

D. Incorrect command structure

Missing required keywords and correct command hierarchy

E. Software Management → Install does NOT create volumes

This installs to an existing volume only

The GUI install dialog does not create new boot volumes

Thus, only Option A and Option C properly create a new software volume.

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.

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.

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 the only supported location from 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.

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 .

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

If an administrator provisions a module that the device is not licensed to run, the system will still allow the provisioning action to occur initially , but the system detects the mismatch and displays an alert.

What actually happens:

The GUI places a warning banner in the upper-left corner labeled 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-IP does allow provisioning, but warns afterward.

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

The warning does not appear during the provisioning step itself.

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