When logged into the bash shell of a BIG-IP system, there are two valid ways to view the management-ip address:
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 the official tmsh method for viewing the management-ip configuration.
C). ifconfig mgmt
In the underlying Linux OS, the management interface maps to the mgmt interface.
Running:
ifconfig mgmt
displays:
Assigned management IP
Netmask
Link-level status
This is a valid Linux-level method used frequently for troubleshooting.

Access to the BIG-IP Configuration Utility (TMUI) is controlled through the /sys httpd allow list.
This list defines which IP addresses or subnets are allowed to connect to the management web interface.
To allow two new subnets--172.28.31.0/24 and 172.28.65.0/24--the administrator must add both subnets to the existing list without removing current entries.
In tmsh, subnet entries must be specified in network/netmask format, for example:
172.28.31.0/255.255.255.0
The correct tmsh command to append these networks is:
modify /sys httpd allow add { 172.28.31.0/255.255.255.0 172.28.65.0/255.255.255.0 }

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.

After a successful upgrade, the system automatically restarts and applies the newly uploaded software version.