When starting all services in a 8 node cluster - only one host runs the check service scripts against mapreduce, zookeeper, etc... is this expected?

[Scott Creeley <sc...@redhat.com>]

Hi Everyone,
One of my colleagues has a 8 node cluster using Ambari 1.6.1 and 2.1.GlusterFS stack.  All is working well, but we noticed that when we start all services one host in particular takes about 2 minutes longer to come up and be fully operational - when looking a bit deeper at this we see that only this host is running some service checks and smoke tests.  MapReduce runs some checks that takes about 35 seconds and then Zookeeper runs some smoke tests that take about 1.5 minutes.  So Zookeeper server is installed on 3 hosts and only one of the hosts runs the checks and smoke tests.  Is this normal behavior?  And if so, how does Ambari determine which of the zookeeper server hosts will run the tests? 

Host1 (ambari server, zookeeper server)
Host2 (agent and zookeeper server, zookeeper client)     <-- This is the host that runs all the service checks
Host3 (agent and zookeeper server and zookeeper client)
Host4 agent
Host5 agent
Host6 agent
Host7 agent
Host8 agent