Yesterday I set up a set of 4 swarm hosts -- they're all both managing (with --replication) and have joined the group (consul for discovery).
At first, everything was going well:
time="2015-06-18T22:18:15Z" level=info msg="New leader elected: 10.128.31.224:3376"
time="2015-06-19T02:51:29Z" level=info msg="New leader elected: 10.128.13.40:3376"
time="2015-06-19T13:28:04Z" level=info msg="New leader elected: 10.128.24.95:3376"
time="2015-06-19T13:28:04Z" level=info msg="Cluster leadership acquired"