Hi Cos, Currently, adding services dynamically is not supported in Ambari. It is generally done, as you mentioned through the creation of a stack with the services definition defined within in. I also don't believe we currently support multiple masters on the same cluster. How would one deferientiate which master it should be using in such an environment?
Of course services can be installed independent of Ambari on the hosts inside the cluster...but I don't think that is what you are getting at. Are you expecting the services to have a presence on the UI though installed outside of Ambari? Erin ----- Original Message ----- From: "Konstantin Boudnik" <c...@apache.org> To: dev@ambari.apache.org Sent: Monday, December 1, 2014 6:42:30 PM Subject: About extensibility of Ambari stacks (not inheritance) Guys, I am looking into possible stack extensibility properties of Ambari (not to be confused with inheritance), but haven't been able to derive any final conclusions just yet. Hence, I'd appreciate the input from the people behind the system. I have a few questions about current state of the Ambari (version 1.6.1 and coming 1.7, and possibly later?) with regards to ability to expand an existing stack definitions with a 3rd party services and do it in the runtime, rather than only during the installation. We need to be able to run a multiple instances of our master service in the cluster, which isn't typical for "normal" Hadoop concept where only one master can exist for any giving service. Our use case is to be able to amend an exiting cluster setup (HDP, Bigtop, etc.) with a new service running on top of HDFS; but not to reinstall the whole stack. The reason we have the use case is that oftentimes our software is being added to an existing 3rd party environment, as an added bonus, not available during the initial planning and setup of the cluster. The way I understand Ambari's stack inheritance is that a scion stack will be a brand new entity, e.g. I won't be able to cherry-pick services from it and add them to the already installed parent stack's cluster, right? So far from I see it doesn't seem possible without introducing a brand-new version of a stack e.g. 'stack inheritance'. Which, unfortunately, won't work as per my explanation of the use above case. I guess another way to look at it is this: would it be possible to add a component (or a service) that will override an existing component or a service, but without a need to reinstall the rest of the stack? Thanks in advance for any info/ideas. Cos
