host           string
		expectedIPList set.StringSet
		expectedErr    error
	}{
		{"localhost", set.CreateStringSet("127.0.0.1"), nil},
	}

	for _, testCase := range testCases {
		ipList, err := getHostIP(testCase.host)
		switch {
		case testCase.expectedErr == nil:
			if err != nil {
				t.Fatalf("error: expected = <nil>, got = %v", err)
			}
		case err == nil: