Failover

How it is used

'Failover' is the noun and 'fail over' the verb: 'The firewall failed over to the secondary.' Engineers configure, test and trigger failover; returning to the primary afterwards is called failback. A failover test in a maintenance window shows whether redundancy really works.

Example sentences

1. Failover to the backup line took about 30 seconds, and most users didn't notice.

2. We'll run a failover test on the firewall cluster on Saturday night.

Common collocations

• automatic failover
• failover test
• fail over to the backup
• failover time
• failback

Related terms

• redundancyHaving extra devices, links or power supplies in place so that the network keeps working if one of them fails.
• downtimeThe total time during which a system, link or service is not available, whether because of a fault or because of planned work.
• load balancerA device or service that spreads incoming traffic across several servers, so that no single server is overloaded and the service stays available if one server fails.
• go downTo stop working or become unreachable; used for links, servers, services and whole networks. The opposite is 'come back up' or 'be back up'.
• maintenance windowAn agreed period, usually at night or at the weekend, when engineers are allowed to make changes that may interrupt service, such as software upgrades and hardware swaps.

This word in other fields

The same English word can have a different meaning in another field:

• failover · Software Engineering
• failover · Cloud Computing & DevOps
• failover · Databases & SQL

More terms: Bandwidth, Latency and Reliability

• bandwidth
• latency
• throughput
• packet loss
• jitter
• QoS
• bottleneck
• congestion
• round-trip time