Tie-breakers are additional heuristics that allow a CLUSTER PARTITION to decide WHETHER or not it is quorate in the event of an even-split - prior to fencing. 

With such a tie-breaker, nodes not only monitor each other, but also an upstream ROUTER that is on the same path as cluster communications. If the two nodes lose contact with each other, the one that wins is the one that can still ping the upstream router.That is why, even when using tie-breakers, it is important to ENSURE that fencing is configured correctly.

CMAN has no internal tie-breakers for various reasons. However, tie-breakers can be implemented using the API.

Tie-breakers are additional heuristics that allow a cluster partition to decide whether or not it is quorate in the event of an even-split - prior to fencing. 

With such a tie-breaker, nodes not only monitor each other, but also an upstream router that is on the same path as cluster communications. If the two nodes lose contact with each other, the one that wins is the one that can still ping the upstream router.That is why, even when using tie-breakers, it is important to ensure that fencing is configured correctly.

CMAN has no internal tie-breakers for various reasons. However, tie-breakers can be implemented using the API.