Fault management
In network management
Network management
Network management refers to the activities, methods, procedures, and tools that pertain to the operation, administration, maintenance, and provisioning of networked systems....

, fault management is the set of functions that detect, isolate, and correct malfunctions in a telecommunications network, compensate for environmental changes, and include maintaining and examining error logs, accepting and acting on error detection notifications, tracing and identifying faults, carrying out sequences of diagnostics tests, correcting faults, reporting error conditions, and localizing and tracing faults by examining and manipulating database
A database is an organized collection of data for one or more purposes, usually in digital form. The data are typically organized to model relevant aspects of reality , in a way that supports processes requiring this information...

Information in its most restricted technical sense is a message or collection of messages that consists of an ordered sequence of symbols, or it is the meaning that can be interpreted from such a message or collection of messages. Information can be recorded or transmitted. It can be recorded as...


When a fault or event occurs, a network component will often send a notification to the network operator using a protocol such as SNMP
Simple Network Management Protocol
Simple Network Management Protocol is an "Internet-standard protocol for managing devices on IP networks. Devices that typically support SNMP include routers, switches, servers, workstations, printers, modem racks, and more." It is used mostly in network management systems to monitor...

. An alarm is a persistent indication of a fault that clears only when the triggering condition has been resolved. A current list of problems occurring on the network component is often kept in the form of an active alarm list such as is defined in RFC 3877,the Alarm MIB
Management information base
A management information base is a virtual database used for managing the entities in a communications network. Most often associated with the Simple Network Management Protocol , the term is also used more generically in contexts such as in OSI/ISO Network management model...

. A list of cleared faults is also maintained by most network management
Network management
Network management refers to the activities, methods, procedures, and tools that pertain to the operation, administration, maintenance, and provisioning of networked systems....


Fault management systems may use complex filtering systems to assign alarms to severity levels. These can range in severity from debug to emergency, as in the syslog
Syslog is a standard for computer data logging. It allows separation of the software that generates messages from the system that stores them and the software that reports and analyzes them...

 protocol. Alternatively, they could use the ITU X.733 Alarm Reporting Function's perceived severity field. This takes on values of cleared, indeterminate, critical, major, minor or warning. Note that the latest version of the syslog protocol draft under development within the IETF includes a mapping between these two different sets of severities. It is considered good practice to send a notification not only when a problem has occurred, but also when it has been resolved. The latter notification would have a severity of clear.

A fault management console allows a network administrator
Network administrator
A network administrator, network analyst or network engineer is a person responsible for the maintenance of computer hardware and software that comprises a computer network...

 or system operator to monitor events from multiple systems and perform actions based on this information. Ideally, a fault management system should be able to correctly identify events and automatically take action, either launching a program or script to take corrective action, or activating notification software that allows a human to take proper intervention (i.e. send e-mail
Electronic mail, commonly known as email or e-mail, is a method of exchanging digital messages from an author to one or more recipients. Modern email operates across the Internet or other computer networks. Some early email systems required that the author and the recipient both be online at the...

 or SMS text
Text messaging
Text messaging, or texting, refers to the exchange of brief written text messages between fixed-line phone or mobile phone and fixed or portable devices over a network...

 to a mobile phone
Mobile phone
A mobile phone is a device which can make and receive telephone calls over a radio link whilst moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile network operator...

). Some notification systems also have escalation rules that will notify a chain of individuals based on availability and severity of alarm.


There are two primary ways to perform fault management - these are active and passive. Passive fault management is done by collecting alarms from devices (normally via SNMP) when something happens in the devices. In this mode, the fault management system only knows if a device it is monitoring is intelligent enough to generate an error and report it to the management tool. However, if the device being monitored fails completely or locks up, it won't throw an alarm and the problem will not be detected. Active fault management addresses this issue by actively monitoring devices via tools such as ping
Ping is a computer network administration utility used to test the reachability of a host on an Internet Protocol network and to measure the round-trip time for messages sent from the originating host to a destination computer...

to determine if the device is active and responding. If the device stops responding, active monitoring will throw an alarm showing the device as unavailable and allows for the proactive correction of the problem.

Fault management includes any tools or procedure for diagnosing testing or repairing the network when a failure occurs.
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