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title
Details of concurrent startup of two locators when the
locators are preferred as membership coordinators.  This
diagram focuses on the second locator, L2
end title
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entity L1 #grey
entity C
entity L2

note right of L2
L1 and L2 have been killed.  C
detects loss and becomes coordinator.
L1 and L2 are restarted simultaneously
end note

L1 -> C : JoinRequest
C -> L1 : prepare/install view(coord=C,L1)

L2 -> L1 : recover
L1 --> L2 : old view + L1
note right of L2
L2 will try to join with L1 and then
fall into findCoordinatorFromView
end note

L2 -> L1 : JoinRequest
L1 -> L1 : queues JoinRequest from L2

C -> L1 : install view(coord=C,L1)
note left: L1 is a member now

L2 -> C : FindCoordinator
note right: (sent via UDP)
C --> L2 : response(coord=C)
note right
At this time C is still coordinator and
will tell L2, who will try to join with it
end note

L1 -> C : prepare/install view(coord=L1,C)

L2 -> C : JoinRequest
C --> L2 : JoinResponse(coord=L1)
note right
C has received the deposing view from L1
and will respond to L2's JoinRequest with
a response telling it that L1 is now coordinator
end note

L2 -> L2 : waits for response to initial JoinRequest 
L1 --> L2 : prepare/install view(coord=L1,C,L2)
L2 -> L2 : continues startup