Oracle Grid Infrastructure 18c patching part 2: Independent Local-mode Automaton architecture and activation

The first important step before starting using the new Independent Local-mode Automaton is understanding which are its components inside a cluster.

Resources

Here’s the list of service that you will find when you install a Grid Infrastructure 18c:

As you can see, there are 4 components that are OFFLINE by default:

Three local resources (that are present on each node):

  • ora.MGMT.GHCHKPT.advm
  • ora.mgmt.ghchkpt.acfs
  • ora.helper

One cluster resource (active on only one server at a time, it can relocate):

  • ora.rhpserver

If you have ever worked with 12c Rapid Home Provisioning, those name should sound familiar.

The GHCHKPT filesystem (ant its relative volume), is used to store some data regarding the ongoing operations across the cluster during the GI home move.

The ora.helper is the process that actually does the operations. It is local because each node needs it to execute some actions at some point.

The rhpserver is the server process that coordinates the operations and delegates them to the helpers.

All those services compose the independent local-mode automaton, that is the default deployment. The full RHP framework (RHP Server and RHP Client) might be configured instead with some additional work.

Important note: Just a few weeks ago Oracle changed the name of Rapid Home Provisioning (RHP) to Fleet Patching and Provisioning (FPP). The name is definitely more appealing now, but it generates again some confusion about product names and acronyms, so beware that in this series sometimes I refer to RHP, sometimes to FPP, but actually it is the same thing.

Tomcat?

You might have noticed that tomcat is deployed now in the GI home, as there are patches specific to it (here I paste the 18.4 version):

 

Indeed Tomcat is registered in the inventory and patched just like any other product inside the OH:

 

Out of the box, Tomcat is used for the Quality of Services Management (ora.qosmserver resource):

But it is used for the Independent Local Mode Automaton as well, when it is started.

Enabling and starting the independent local-mode automaton

The resources are started using the following commands (as root, the order is quite important):

Before continuing with the rhpserver resource, you might want to check if the filesystem is mounted:

Now the rhpserver should start without problems, as oracle:

Please note that if you omit to activate the filesystem first, the rhpserver will fail to start.

As you can see, now both rhpserver and the helper are online:

Now all is set to start using it!

We’ll see how to use it in the next posts.

Ludo