server/src/test/java/org/elasticsearch/health/node/DiskHealthIndicatorServiceTests.java
assertThat(
                dataDiagnosisDefinition.action(),
                equalTo(
                    "Enable autoscaling (if applicable), add disk capacity or free up disk space to resolve this. If you have already "
                        + "taken action please wait for the rebalancing to complete."
                )
            );
        }
        {
            Diagnosis diagnosis = diagnosisList.get(1);
            List<Diagnosis.Resource> masterAffectedResources = diagnosis.affectedResources();
            assertThat(masterAffectedResources.size(), equalTo(1));
            assertThat(masterAffectedResources.get(0).getType(), is(Diagnosis.Resource.Type.NODE));
            assertThat(masterAffectedResources.get(0).getNodes().size(), is(numberOfRedMasterNodes));
            Diagnosis.Definition masterDiagnosisDefinition = diagnosis.definition();
            assertThat(masterDiagnosisDefinition.cause(), equalTo("Disk is full."));
            assertThat(
                masterDiagnosisDefinition.action(),
                equalTo("Please add capacity to the current nodes, or replace them with ones with higher capacity.")
            );
        }
        {
            Diagnosis diagnosis = diagnosisList.get(2);
            List<Diagnosis.Resource> nonDataNonMasterAffectedResources = diagnosis.affectedResources();
            assertThat(nonDataNonMasterAffectedResources.size(), equalTo(1));
            assertThat(nonDataNonMasterAffectedResources.get(0).getType(), is(Diagnosis.Resource.Type.NODE));
            assertThat(nonDataNonMasterAffectedResources.get(0).getNodes().size(), is(numberOfRedOtherNodes));
            Diagnosis.Definition nonDataNonMasterDiagnosisDefinition = diagnosis.definition();
            assertThat(nonDataNonMasterDiagnosisDefinition.cause(), equalTo("Disk is full."));
            assertThat(