This graphic shows four instances where host1 and host3 have a connection to each other and host2 and host4 have a connection to each other. There is a communication error where host1 and host3 do not know about host2 and host4. There are also three Zookeeper membership servers. The ms_host1 membership server was used by host1 and host3, but with the communication error, the membership server does not know about ms_host2 and ms_host3 membership servers. Since a single membership server is not a majority, it no longer accepts requests from host1 and host3.