org.jgroups.protocols
Class FD
Failure detection based on simple heartbeat protocol. Regularly polls members for
liveness. Multicasts SUSPECT messages when a member is not reachable. The simple
algorithms works as follows: the membership is known and ordered. Each HB protocol
periodically sends an 'are-you-alive' message to its *neighbor*. A neighbor is the next in
rank in the membership list, which is recomputed upon a view change. When a response hasn't
been received for n milliseconds and m tries, the corresponding member is suspected (and
eventually excluded if faulty).
FD 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.
When a message is received from the monitored neighbor member, it causes the pinger thread to
'skip' sending the next are-you-alive message. Thus, traffic is reduced.
When we receive a ping from a member that's not in the membership list, we shun it by sending it a
NOT_MEMBER message. That member will then leave the group (and possibly rejoin). This is only done if
shun
is true.
Version:
- Bela Ban
down_handler , down_prot , down_queue , down_thread , down_thread_prio , log , observer , props , stack , up_handler , up_prot , up_queue , up_thread , up_thread_prio |
destroy , down , getDownProtocol , getDownQueue , getName , getProperties , getUpProtocol , getUpQueue , handleSpecialDownEvent , init , passDown , passUp , providedDownServices , providedUpServices , receiveDownEvent , receiveUpEvent , requiredDownServices , requiredUpServices , setDownProtocol , setObserver , setProperties , setPropertiesInternal , setProtocolStack , setUpProtocol , start , startDownHandler , startUpHandler , stop , stopInternal , up |
getName
public String getName()
- getName in interface Protocol
init
public void init()
throws Exception
- init in interface Protocol
setProperties
public boolean setProperties(Properties props)
- setProperties in interface Protocol
stop
public void stop()
- stop in interface Protocol
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