Difference between worker and manager?

Open Source Projects Swarm
1

Hi,

In Swarm mode, we have two main node types, worker and manager.
But the documentation says that a manager is like a worker node and will run a service also.
So what is the difference between a worker and a manager?
In which case should I use worker node if a manager node can do both, run containers and manage the swarm cluster?

Regards,
Leo

2

While a manager node can also run service containers (unless you define a different scheduling rule), the thing that manager nodes do that worker nodes can’t is to coordinate the cluster quorum - it’s the machine telling the others (and itself) what to do.

3

hi, I’m new to docker and this was important question for me… let me followup
if master node is cluster “admin” and quorum manager, than an effective cluster has more than 1 master in case of server failure, is that safe to assume?
an effective cluster in most linux product is a 3 way “masters” ? is it the case in docker ?

essentially, if you have a 2+ physical docker server running the demon, than you will add a 3rd, 4th …n as a worker… but if you have a 2 or 3 nodes probably they will all be master?
is that the case?