| title Replication - Split Brain Detected | 
 |  | 
 | participant Client1  | 
 | participant Instance1 | 
 | participant Global Ref-DB | 
 | participant Instance2 | 
 | participant Client2 | 
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 | state over Client1, Client2, Instance1, Instance2: W0 | 
 | state over Client1 : W0 -> W1 | 
 | Client1 -> +Instance1: Push W1 | 
 | Instance1 -> +Global Ref-DB: CAS if state == W0 set state W0 -> W1 | 
 | state over Global Ref-DB : W0 -> W1 | 
 | Global Ref-DB -> -Instance1 : ACK | 
 | state over Instance1 : W0 -> W1 | 
 | Instance1 -> -Client1: Ack W1 | 
 |  | 
 | state over Instance1 : Crash | 
 |  | 
 | state over Client2 : W0 -> W2 | 
 | Client2 -> +Instance2: Push W2 | 
 |  | 
 | Instance2 -> +Global Ref-DB: CAS if state == W0 set state W0 -> W2 | 
 | Global Ref-DB -> -Instance2 : NACK | 
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 | Instance2 -> -Client2 : Push failed -- RO Mode | 
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 | state over Instance1:  Restart | 
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 | Instance1->Instance2: Replicate W1  | 
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 | state over Instance2 : W0 -> W1 | 
 |  | 
 | Client2 -> +Instance2: Pull W1 | 
 | Instance2 -> Client2 : Missing W1 | 
 | Client2 -> Instance2: Pull W1 | 
 | state over Client2 : W0 -> W1 -> W2 | 
 | Client2 -> Instance2: Push W2 | 
 | Instance2 -> +Global Ref-DB: CAS if state == W1 set state W1 -> W2 | 
 | state over Global Ref-DB: W0 -> W1 -> W2 | 
 | Global Ref-DB -> -Instance2 : ACK | 
 | state over Instance2: W0 -> W1 -> W2  | 
 | Instance2 -> -Client2 : ACK  | 
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