F5 F5CAB1 Practice Test Questions Answers

When logged into thebash shellof a BIG-IP system, there are two valid ways to view themanagement-ipaddress:

A. tmsh list /sys management-ip

Even from the bash shell, the administrator can enter a tmsh command by typing:

tmsh list /sys management-ip

This displays:

Management IP address

Netmask

Any configured management routes

This is theofficial tmsh methodfor viewing the management-ip configuration.

C. ifconfig mgmt

In the underlying Linux OS, the management interface maps to themgmtinterface.

Running:

ifconfig mgmt

displays:

Assigned management IP

Netmask

Link-level status

This is a valid Linux-level method used frequently for troubleshooting.

Why the other options are incorrect:

B. show mgmt ip

Not a valid bash or tmsh command on BIG-IP.

D. list / sys management-ip

Missing thetmshprefix.

In bash, this will generate a syntax error.

The correct form requires:

tmsh list /sys management-ip

The screenshot shown is from theUser Administrationsection of the BIG-IP GUI.

This section controls:

Root and Admin passwords

SSH Access

SSH IP Allow settings

However,it does not contain any controls for restricting access to the WebUI (TMUI).

BIG-IP does not provide TMUI access restrictions from this part of the GUI.

Access to the web-based Configuration Utility is controlled by thehttpd allow list, configured through TMSH:

tmsh modify /sys httpd allow { }

This setting is not displayed in the User Administration panel, and in many BIG-IP versions, the httpd allow list isonly configurable from the CLI, not the GUI.

Therefore, the administrator cannot find the setting in the screen shown because:

TMUI access restriction isnotlocated in this GUI section

It must be configured usingtmshunder/sys httpd allow

This is whyOption Ais correct.

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.

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.

Self-IPs implement a security feature known asPort Lockdown, which limits which services are reachable on a Self-IP.

However, certain services required for BIG-IP device-to-device communication bypass Port Lockdown to ensure cluster and HA functionality.

TCP 4353

TCP port4353is used byDevice Service Clustering (DSC)for:

Device trust establishment

Configuration synchronization

Failover communication

Because BIG-IP devices must always be able to communicate for HA functions to remain operational, port 4353 isexempt from Port Lockdown rules.

Why the other options are incorrect

A. TCP 443

Not required for device trust or synchronization.

HTTPS access is fully controlled by Port Lockdown.

C. UDP 53

DNS traffic is not required for synchronization and has no exemption under Port Lockdown.