fix: skip hardware fabric default when Spectrum-X forces ethernet

[andrewwhitecdw]

This PR addresses the following issue in pkg/resolve/defaults.go: skip hardware fabric default when Spectrum-X forces ethernet.

Changes

• pkg/resolve/defaults.go: skip hardware fabric default when Spectrum-X forces ethernet.

Details

--- a/pkg/resolve/defaults.go
+++ b/pkg/resolve/defaults.go
@@ -1,3 +1,5 @@
-	// --fabric ----------------------------------------------------------
-	if cfg.Profile.Fabric == "" && opts.Fabric == "" {
-		fabric, ok, reason := dominantLinkType(cfg.ClusterConfig)
+	// --fabric ----------------------------------------------------------
+	// Spectrum-X forces ethernet fabric; skip hardware linkType default
+	// when active so the Spectrum-X branch can default it to ethernet.
+	if cfg.Profile.Fabric == "" && opts.Fabric == "" && !opts.SpectrumX && !cfgHasSpectrumX {
+		fabric, ok, reason := dominantLinkType(cfg.ClusterConfig)

Tests

• pkg/resolve/defaults_test.go

--- a/pkg/resolve/defaults_test.go
+++ b/pkg/resolve/defaults_test.go
@@ -0,0 +1,66 @@
+func TestApplyHardwareDefaults_SpectrumXSkipsFabricHardwareDefault(t *testing.T) {
+	// An InfiniBand cluster should not leave fabric=infiniband when the
+	// user enabled Spectrum-X on the CLI; the Spectrum-X branch must force
+	// ethernet.
+	cfg := &config.LaunchKitConfig{
+		ClusterConfig: []config.ClusterConfig{
+			{Identifier: "group-1", LinkType: "InfiniBand"},
+		},
+		Profile: &config.Profile{},
+	}
+	opts := options.Options{SpectrumX: true}
+
+	decisions := ApplyHardwareDefaults(cfg, opts)
+
+	if cfg.Profile.Fabric != "ethernet" {
+		t.Errorf("Spectrum-X should force fabric=ethernet, got %q", cfg.Profile.Fabric)
+	}
+
+	found := false
+	for _, d := range decisions {
+		if d.Flag == "--fabric" && d.Value == "ethernet" && d.Reason == "implied by --spectrum-x" {
+			found = true
+		}
+	}
+	if !found {
+		t.Errorf("expected Spectrum-X fabric default decision, got %v", decisions)
+	}
+}
+
+func TestApplyHardwareDefaults_ConfigSpectrumXSkipsFabricHardwareDefault(t *testing.T) {
+	// Spectrum-X can also come from the config file; hardware default must
+	// still be skipped so fabric is forced to ethernet.
+	cfg := &config.LaunchKitConfig{
+		ClusterConfig: []config.ClusterConfig{
+			{Identifier: "group-1", LinkType: "InfiniBand"},
+		},
+		Profile: &config.Profile{
+			SpectrumX: &config.ProfileSpectrumX{Enable: true},
+		},
+	}
+	opts := options.Options{}
+
+	decisions := ApplyHardwareDefaults(cfg, opts)
+
+	if cfg.Profile.Fabric != "ethernet" {
+		t.Errorf("Spectrum-X should force fabric=ethernet, got %q", cfg.Profile.Fabric)
+	}
+
+	found := false
+	for _, d := range decisions {
+		if d.Flag == "--fabric" && d.Value == "ethernet" && d.Reason == "implied by --spectrum-x" {
+			found = true
+		}
+	}
+	if !found {
+		t.Errorf("expected Spectrum-X fabric default decision, got %v", decisions)
+	}
+}

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[greptile-apps]

Greptile Summary

This PR prevents hardware discovery from assigning an InfiniBand fabric before the Spectrum-X-specific defaulting branch can force Ethernet.

• Skips dominantLinkType fabric defaulting when Spectrum-X is enabled through either CLI options or configuration.
• Preserves the existing non-Spectrum-X hardware-defaulting path.

Confidence Score: 5/5

The PR appears safe to merge because every newly skipped hardware-default path reaches the Spectrum-X branch that assigns Ethernet.

The new condition uses the same Spectrum-X activation signals as the subsequent defaulting branch, while explicit CLI fabric values retain precedence and contradictory values remain subject to validation.

Important Files Changed

Filename	Overview
pkg/resolve/defaults.go	The updated guard aligns with the downstream Spectrum-X activation condition, which reliably assigns Ethernet while leaving ordinary hardware defaulting unchanged.

_{Reviews (1): Last reviewed commit: "fix: skip hardware fabric default when S..." | Re-trigger Greptile}