@Philippe Kevorkian Please leave all the line linked ti IPv6 and update the line as stated by Sandeep, but I am wondering what is the output of the below commands $ hostname or vi /etc/hostname Run the below command to get your ip, please append sudo where needed $ ifconfig The above steops should give you the output to add in your /etc/hosts the format is IP/hostname/Alias eg 192.145.90.10 myhdp.ubuntu.com myhdp With the above entry you can the Alias during the registration of the hosts in Ambari HTH ... View more