diff --git a/metropolis/pkg/bootparam/params_test.go b/metropolis/pkg/bootparam/params_test.go
new file mode 100644
index 0000000..c76dd88
--- /dev/null
+++ b/metropolis/pkg/bootparam/params_test.go
@@ -0,0 +1,43 @@
+package bootparam
+
+import "testing"
+
+func TestConsoles(t *testing.T) {
+	cases := []struct {
+		name     string
+		cmdline  string
+		consoles []string
+	}{
+		{"Empty", "", []string{}},
+		{"None", "notconsole=test", []string{}},
+		{"Single", "asdf=ttyS1 console=ttyS0,115200", []string{"ttyS0"}},
+		{"MultipleSame", "console=ttyS0 noop console=ttyS0", []string{"ttyS0"}},
+		{"MultipleDiff", "console=tty27 console=ttyACM0", []string{"tty27", "ttyACM0"}},
+		{"WithDev", "console=/dev/ttyXYZ0", []string{"ttyXYZ0"}},
+		{"BrokenBadDev", "console=/etc/passwd", []string{}},
+		{"BrokenNoValue", "console=", []string{}},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			p, _, err := Unmarshal(c.cmdline)
+			if err != nil {
+				t.Fatalf("Failed to parse cmdline %q: %v", c.cmdline, err)
+			}
+			consoles := p.Consoles()
+			wantConsoles := make(map[string]bool)
+			for _, con := range c.consoles {
+				wantConsoles[con] = true
+			}
+			for con := range wantConsoles {
+				if !consoles[con] {
+					t.Errorf("Expected console %s to be returned but it wasn't", con)
+				}
+			}
+			for con := range consoles {
+				if !wantConsoles[con] {
+					t.Errorf("Didn't expect console %s to be returned but it was", con)
+				}
+			}
+		})
+	}
+}