What is an IP address; where are IP addresses defined in TR7?

Short answer

An IP address is the address that identifies an interface on an IP network and specifies the destination the packets will go to (RFC 791 for IPv4, RFC 8200 for IPv6). In TR7, IP addresses are added to an interface with the Add IP form on the Network → Interfaces screen; the address is valid in the route table the interface is bound to. A vService does not create an address; it only selects one from the Frontend IP list. For this reason, even if the vService is deleted, the IP remains defined on the interface until it is deleted with Delete IP, and it continues to respond on the network unless it is disabled with Disable for (the profile-based IP model). In a cluster, the Ip Type field selects between two types of address: the Interface IP, which belongs to each device and does not move to the peer device, and the VIP, which runs on the Master device and moves to the peer device on failure.

Where It Is Used in TR7

Where	Field / label	What for
Network → Interfaces → Actions → Add IP (or right-click on the interface → Add IP)	Add IP form: IP Interface, Ip Type, the IP table and CIDR, IP Status	Adding one or more addresses to an interface
The Network → Interfaces list	The IP column that carries the device name as its header (Interfaces List); in a cluster, a separate column for each device, the VIPs with the (M) / (S) suffix	Monitoring the addresses and their statuses
Right-click on an IP address	Edit IP, Delete IP, Disable for / Enable for (with the device name) (Right-clicking an IP address)	Editing or deleting the address, disabling it on one device
vService form → frontend row	The Frontend IP list; the Add IP in the list opens the same form as a window	Selecting the address the vService will listen on
WEB-CLI	network ip add, network ip list (network ip)	Adding and listing addresses

The Life Cycle of an IP Address in TR7

1. Adding: The address is added to an interface; its route table is the route table of the selected interface. If an address that is already defined in the same route table is added again, the record is rejected with the IP collision error (What is an IP conflict; how does TR7 check for it?).
2. Using: The address appears in the vService's Frontend IP list and is selected there. One address can be used in more than one vService with different ports.
3. Removing: An address removed from a vService, or the address of a deleted vService, remains on the interface. To remove the address, Delete IP is used; to disable it on only one device, Disable for is used. An address defined in the management access lists (HTTP, HTTPS, SSH, SNMP) cannot be deleted and cannot be disabled with Disable for.

In a cluster, the address definition is common to the two devices and, with the default auto-sync, is applied on the peer device as well. Two addresses are entered in the Interface IP row (this device and the peer device); a single address is entered in the VIP row, and Master/slave selects the device on which it will normally run. The type of address used in a vService: Which IP address can I use for a vService; what is the difference between an Interface IP and a VIP?

Common Misconceptions

• "When the vService is deleted, the IP is deleted too." The IP remains on the interface and continues to respond on the network; an address that is not in use is removed with Delete IP.
• "The IP address is typed manually in the vService form." The Frontend IP is selected from the list; an address that is not in the list is first added to an interface (Why can't I type the Frontend IP manually; what should I do to use an IP that is not in the list (e.g. IPv6) on a vService?).
• "In a cluster, every address moves to the peer device on failure." Only the VIP moves; the Interface IP is each device's own address.

How it is done in the documentation

• Add IP Address · What Is Add IP Address?
• Add IP Address · The IP Types in Cluster Mode
• Add IP Address · The Profile-Based IP Model
• Interfaces List · Right-Clicking an IP Address

Related questions

• Which IP address can I use for a vService; what is the difference between an Interface IP and a VIP?
• Why can't I type the Frontend IP manually; what should I do to use an IP that is not in the list (e.g. IPv6) on a vService?
• What is the difference between IPv4 and IPv6?
• What is an IP conflict; how does TR7 check for it?