messaging - In a Master-Slave cluster, how to make sure the master is really dead for the slave to take over? -

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i have in-house messaging system, similar message broker. have 1 master message broker , 1 slave message broker. message broker receives messages , sends them nodes. slave acting node, receiving messages master , building state can take on in case of master failure.

now problem is: how can detect, if possible , without human intervention, master dead!? master may dead, , slave might tempted take over, might end in situation of 2 masters in system.

i'm trying understand how clustering systems implement master-dead detection. until looks human has manually kill master , turn on slave, more preferable process automatic.


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