Leader Election Strategies
Understand how distributed systems maintain coordination by electing a leader to reduce client overhead and manage sequencing. Learn several leader election strategies including the bully algorithm, next-in-line failover, candidate optimization, and ring algorithm. Gain insights into how failures are detected and new leaders are chosen efficiently to maintain system reliability and consensus.
We'll cover the following...
In a distributed environment, it is expensive if the client connects to every host. To reduce this overhead, distributed systems rely on the existence of a leader responsible for sequencing and coordinating with the rest of the hosts.
Since the leadership role is temporary and every leader will eventually fail, it must detect failures and the system has to elect a new leader to replace the failed one.
In this section, we will discuss the following leader election strategies:
Bully algorithm
Next-in-line failover
Candidate/Ordinary optimization
Ring algorithm
Bully algorithm
In the bully algorithm, each host in the distributed environment has a rank. The host with the highest rank is chosen as the leader during the election process. The algorithm is called bully because the hosts with the highest ranks always bully the ones with lower ranks.
This is the sequence of steps in a bully algorithm:
First, the distributed system identifies that the current leader is down.
Next, the system sends leader election notifications to hosts with higher identifiers. ...