This error message similar to the following two, which "localhost.localdomain" will be slightly different.
Agent Host CAN not the REACH Ambari Ambari Server 'localhost.localdomain: 8080'
Ambari Agent Machine hostname (localhost.localdomain) does not match expected ambari Server hostname
1. Check the hostname of each node
hostname -f
2. Check each node hosts file
sudo vim / etc / hosts
# Check whether the correct IP corresponding hostname
# The following two lines of the original can not be deleted, otherwise it will lead to other abnormal
127.0.0.1 localhost.localdomain localhost
:: 1 localhost6.localdomain6 localhost6
3. Check ambari-agent.ini file
vim /etc/ambari-agent/conf/ambari-agent.ini
# Check corresponds hostname = xxx above hostname