Question

I am exploring various architectures in cluster computing. Some of the popular ones are:

1. Master-Slave.
2. RPC
3. …

In Master-slave, the normal way is to set one machine as master & a bunch of machines as slaves controlled by master. One particular algo here got me interested. It’s called Leader-Election Algo which has a certain randomness in selecting which of the machines will become master.

My question is – Why would anyone want to elect a master machine this way? What advantages does this approach have compared to manually selecting a machine as master?

Answer 1

There are some advantages with this algorithms:

1. Selection of node as leader will be
   done dynamically so for example you
   can select node with highest
   performance, and arrival of new
   nodes may be makes better choice.

2. Another good approach by dynamically
   selecting leader is, if one of a
   nodes have major fault (for example
   PC is shutting down) you have other
   choices and there is no need to
   manually change the leader.

3. if you manually select node should
   manually configure all other nodes
   to use this node, and also set their
   time manually, … but this
   algorithms will help you to handle
   timing issues.

4. for example (not very relevant) why
   in most cases using DHCP? too many
   configs will be handeled by this
   algorithms.