Element Properties: Basics

Element ID: Each element has a unique id number. Elements are numbered in the order they are added to the system model.

Type: One of the element types listed in the table below.


Option	Description
HA System	HASystem element represents the entire managed system and is the top-level object in each syst
COMPUTERSYSTEM	Computer System represents a computer including the hardware and operating system. When a computer system has a HAC instance, it is considered as a HAC node with the same name as the computer system element. HAC instances use the configured addresses to communicate with each other as well as for ICMP pinging for determining whether the computer system is online or not.
RedundantSystem	Redundant system represents a group of equivalent and redundant elements. The redundant elements are the instances of the redundant system. Redundant system automatically manages the roles of the instance elements in order to maintain the appropriate number of its instances active and/or in the standby mode at all times. Instances are prioritized primarily by the instance element’s name and secondarily by the instance element’s element ID. Typical virtual unit is modelled in HAC with a redundant system element having one instance on each node the virtual unit’s software has been installed.
Service	Service element represents a group of elements that are managed as a group. If any of the component elements fail, the service elements fail also thus resulting in inactivating the entire service and all its components. A service is often a software element, or collection of software elements. A service element provides a single point of management for its components. Typically, virtual unit instance elements are services. If a component element’s role is set to unassigned, it is not considered as part of the service. Thus, its failure does not cause the service to fail. Service elements are always hosted by (components or subcomponents of) a computer system.
ServiceAccessPoint	Service Access Point represents the point where the element or group of elements can be accessed, such as IP address.
SoftwareElement	Software element represents a software system component, for example an installed application process. Software elements are hosted by a computer system component. Software elements have an attached monitoring and controlling method, several alternative methods exist for different types of software. Software elements may also have optional attached monitor and controller objects, that allow the software element to monitor and control the system component (for example the process and its executable file). Currently the following types of controllers and monitors are available: Windows Service Monitor and Controller: Monitors and controls Microsoft Windows services. Windows Process Monitor and Controller: Monitors and controls Microsoft Windows processes that are started from an executable file. The process controller also supports the Contact Center Stop Event signalling for stopping a Sinch Contact Pro process. Shell Monitor and Controller: Uses given command lines to execute the required action. The return values from the command lines are interpreted as the results of the action. HTTP Monitor: Monitors a web server. It uses HTTP GET to a given web page on a given web server. This monitor also supports the Microsoft IIS web site (and application pool) monitoring. IIS web site controller: Controlling individual Microsoft IIS web sites. The target for the controllers and monitors (the command line, executable file or service name) is defined in the TARGET property. You can use the PARAMETERS property to enter any parameters for the Microsoft Windows services or processes.

Tag: Free-form information

Role: Role of an element controls the desired status of the element. If other conditions (such as dependencies) are met, the element’s Status matches its Role.


Option	Description
Active	The element should be active.
Inactive	The element should be inactive. Use this role when you upgrade software, or turn the system off.
Spare	The element should be in cold standby. This role is used in redundant system for elements that are not active.
Standby	The element should be in hot standby.
Unassigned	The element is intentionally left unassigned. HAC takes no actions to control the element. If a component of a Service element is set to unassigned role, the component is not considered as part of the service and thus, its failure does not cause the service to fail.

Mode: Operational mode is used to modify the behavior of the element in the system. The following values are used:

Normal: The element is participating in the production normally. All monitoring, controlling and recovery actions are performed in the usual way.
Freeze: No automatic recovery actions are performed.
Maintenance: The elements are monitored and managed in a normal way, but the Software elements are not marked as permanently failed nor instability of their status cause the element to fail, and Service elements do not fail even if its components fail.

Status: Status indicates the runtime status of the system component represented by the element. For example, a software element representing a process is active if the process is running, and inactive if the process is not running.


Option	Description
Unknown	The status has not been successfully determined yet.
Active	Participates actively in the production.
Inactive	The element has been shut down and does not participate in the production.
Standby	The element is active, but does not participate in the production. This is considered to be the hot standby mode, and the element may be quickly activated into production from it.
Activating	Proceeding to the active state.
Inactivating	Proceeding to the inactive state.
Standingby	Proceeding to the standby state.
Partially active	The element is partially active.

Health: Describes the system health.


Option	Description
Unknown	The health has not been successfully determined yet.
Normal	The element is acting normally according to its state. If an element is in a transitional state or is inactive, it has normal health if the controlling and monitoring mechanisms are generally available.
Failed	The element has failed permanently and needs manual repair. A major alarm is raised and the HAC attempts to inactivate the element (forcibly if necessary).
Near failure	The element is about to or may fail soon if no actions are taken. A minor alarm is raised to suggest preventive actions.

System Version: Only for HASystem type elements. The number is increased by one every time the system model changes are saved.