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Class JavaGroups.JavaStack.Protocols.FD_RAND 

java.lang.Object
   |
   +----JavaGroups.JavaStack.Protocol
           |
           +----JavaGroups.JavaStack.Protocols.FD_RAND
public class FD_RAND
extends Protocol
implements Runnable
Failure detection based on simple heartbeat protocol. Regularly polls randomly selected members for liveness. Passes SUSPECT message up the stack when a member is not reachable. The simple algorithms works as follows: the membership is known. Each HB protocol periodically sends a 'are-you-alive' message to a randomly selected member, except itself. When a response hasn't been received for n milliseconds and m tries, the corresponding member is suspected (and eventually excluded if faulty).

FD_RAND starts when it detects (in a view change notification) that there are at least 2 members in the group. It stops running when the membership drops below 2.

Constructor Index

o FD_RAND()

Method Index

o Down(Event)
An event is to be sent down the stack.
o GetName()
o run()
Loop while more than 1 member available.
o SetProperties(Properties)
Configures the protocol initially.
o Up(Event)
An event was received from the layer below.

Constructors

o FD_RAND 
 public FD_RAND()

Methods

o GetName 
 public String GetName()
Overrides:
GetName in class Protocol
o SetProperties 
 public boolean SetProperties(Properties props)
Configures the protocol initially.

Overrides:
SetProperties in class Protocol
o Up 
 public void Up(Event evt)
An event was received from the layer below.

Overrides:
Up in class Protocol
o Down 
 public void Down(Event evt)
An event is to be sent down the stack.

Overrides:
Down in class Protocol
o run 
 public void run()
Loop while more than 1 member available. Choose a member randomly (not myself !) and send a heartbeat. Wait for ack. If ack not received withing timeout, mcast SUSPECT message. 

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