Remove useless mechanism to retrieve OS minor version from RHEL and R…

…ocky

This mechanism was used on CentOS 7, to retrieve the OS minor version from the kernel version
and use it to download the right version of the Lustre client.

This mechanism is not required for RHEL and Rocky because the minor version
automatically changes when updating the kernel. This is reflected in the `/etc/os-release` file too.

This change will permit us to automatically support new minor versions when they will be available,
without the need to update the internal mapping.

Signed-off-by: Enrico Usai <[email protected]>

cookbooks/aws-parallelcluster-environment/resources/lustre/lustre_redhat8.rb

@@ -37,28 +37,10 @@
   end
 end
 
-def find_os_minor_version
-  os_minor_version = ''
-  kernel_patch_version = find_kernel_patch_version
-
-  # kernel patch versions under 193 are prior to RHEL 8.2
-  # kernel patch version number can be retrieved from https://access.redhat.com/articles/3078#RHEL8
-  os_minor_version = '2' if kernel_patch_version >= '193'
-  os_minor_version = '3' if kernel_patch_version >= '240'
-  os_minor_version = '4' if kernel_patch_version >= '305'
-  os_minor_version = '5' if kernel_patch_version >= '348'
-  os_minor_version = '6' if kernel_patch_version >= '372'
-  os_minor_version = '7' if kernel_patch_version >= '425'
-  os_minor_version = '8' if kernel_patch_version >= '477'
-  os_minor_version = '9' if kernel_patch_version >= '513'
-
-  os_minor_version
-end
-
 action_class do
   def base_url
     # https://docs.aws.amazon.com/fsx/latest/LustreGuide/install-lustre-client.html#lustre-client-rhel
-    "https://fsx-lustre-client-repo.s3.amazonaws.com/el/8.#{find_os_minor_version}/$basearch"
+    "https://fsx-lustre-client-repo.s3.amazonaws.com/el/#{node['platform_version']}/$basearch"
   end
 
   def public_key

cookbooks/aws-parallelcluster-environment/resources/lustre/lustre_rocky8.rb

@@ -37,28 +37,10 @@
   end
 end
 
-def find_os_minor_version
-  os_minor_version = ''
-  kernel_patch_version = find_kernel_patch_version
-
-  # kernel patch versions under 193 are prior to RHEL 8.2
-  # kernel patch version number can be retrieved from https://access.redhat.com/articles/3078#RHEL8
-  os_minor_version = '2' if kernel_patch_version >= '193'
-  os_minor_version = '3' if kernel_patch_version >= '240'
-  os_minor_version = '4' if kernel_patch_version >= '305'
-  os_minor_version = '5' if kernel_patch_version >= '348'
-  os_minor_version = '6' if kernel_patch_version >= '372'
-  os_minor_version = '7' if kernel_patch_version >= '425'
-  os_minor_version = '8' if kernel_patch_version >= '477'
-  os_minor_version = '9' if kernel_patch_version >= '513'
-
-  os_minor_version
-end
-
 action_class do
   def base_url
     # https://docs.aws.amazon.com/fsx/latest/LustreGuide/install-lustre-client.html#lustre-client-rhel
-    "https://fsx-lustre-client-repo.s3.amazonaws.com/el/8.#{find_os_minor_version}/$basearch"
+    "https://fsx-lustre-client-repo.s3.amazonaws.com/el/#{node['platform_version']}/$basearch"
   end
 
   def public_key

cookbooks/aws-parallelcluster-environment/spec/unit/resources/lustre_setup_spec.rb

@@ -203,6 +203,7 @@ def self.setup(chef_run)
             platform: platform, version: '8',
             step_into: ['lustre']
           ) do |node|
+            node.automatic['platform_version'] = "8.#{minor_version}"
             node.override['cluster']['kernel_release'] = "4.18.0-#{kernel_patch}.9.1.el8"
           end
           Lustre.setup(runner)
@@ -226,26 +227,6 @@ def self.setup(chef_run)
         end
       end
     end
-
-    context "kernel release does not match expected format" do
-      cached(:chef_run) do
-        runner = runner(
-          platform: platform, version: '8',
-          step_into: ['lustre']
-        ) do |node|
-          node.automatic['platform_version'] = "8.2"
-          node.override['cluster']['kernel_release'] = 'unexpected.format'
-        end
-        Lustre.setup(runner)
-      end
-
-      it 'raises error' do
-        expect { chef_run }.to(raise_error do |error|
-          expect(error).to be_a(Exception)
-          expect(error.message).to include("Unable to retrieve the kernel patch version from unexpected.format.")
-        end)
-      end
-    end
   end
 
   for_oses([