A heartbeat is a message sent between machines at a regular interval of the order of seconds. If a heartbeat isn't received for a time -- usually a few heartbeat intervals -- the machine that should have sent the heartbeat is assumed to have failed. A heartbeat protocol is generally used to negotiate and monitor the availability of a resource, such as a floating IP address. Typically when a heartbeat starts on a machine it will perform an election process with other machines on the heartbeat network to determine which, if any machine owns the resource. On heartbeat networks of more than two machines it is important to take into account partitioning, where two halves of the network could be functioning but not able to communicate with each other. In a situation such as this it is important that the resource is only owned by one machine, not one machine in each partition.
As a heartbeat is intended to be used to indicate the health of a machine it is important that the heartbeat protocol and the transport that it runs on is as reliable as possible. Effecting a fail-over because of a false alarm may, depending on the resource, be highly undesirable. It is also important to react quickly to an actual failure, so again it is important that the heartbeat is reliable. For this reason it is often desirable to have heartbeat running over more than one transport, for instance an ethernet segment using UDP/IP, and a serial link.
that is not a heartbeat of a baby. it was your heartbeat..had the same thing happen to me! that is not a heartbeat of a baby. it was your heartbeat..had the same thing happen to me!
What heartbeat :l
- In your own words, define the term 'protocol' and what is the difference between protocol and protocol suite
Pulse = heartbeat
In a Heartbeat ended on 2001-03-25.
No...heartbeat is one word.
Why does the rate of heartbeat change?
My Heartbeat has 160 pages.
The duration of In a Heartbeat is 1800.0 seconds.
Heartbeat is a compound word.
There are various protocols ftp: file transfer protocol smtp: simple mail transfer protocol pop3: post office protocol ip: internet protocol tcp: transmission control protocol ospf: open shortest path first igrp: interior gateway routing protocol eigrp: enhanced interior gateway routing protocol rip: routing information protocol http: hyper text transfer protocol udp: user datagram protocol icmp: internet control message protocol
HTML is a protocol