1 files changed, 47 insertions, 20 deletions

diff --git a/netboot/netconf_integ_test.go b/netboot/netconf_integ_test.go
index 30a7232..099296c 100644
--- a/netboot/netconf_integ_test.go
+++ b/netboot/netconf_integ_test.go
@@ -3,6 +3,9 @@
 package netboot
 
 import (
+	"fmt"
+	"io/ioutil"
+	"log"
 	"net"
 	"testing"
 	"time"
@@ -11,10 +14,9 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-// Travis-CI uses ens4, and this test assumes that such interface
-// exists and is configurable. If you are running this test locally,
-// you may need to adjust this value.
-var ifname = "ens4"
+// The test assumes that the interface exists and is configurable.
+// If you are running this test locally, you may need to adjust this value.
+var ifname = "eth0"
 
 func TestIfUp(t *testing.T) {
 	iface, err := IfUp(ifname, 2*time.Second)
@@ -28,24 +30,49 @@ func TestIfUpTimeout(t *testing.T) {
 }
 
 func TestConfigureInterface(t *testing.T) {
-	nc := NetConf{
-		Addresses: []AddrConf{
-			AddrConf{IPNet: net.IPNet{IP: net.ParseIP("10.20.30.40")}},
+	// Linux-only. `netboot.ConfigureInterface` writes to /etc/resolv.conf when
+	// `NetConf.DNSServers` is set. In this test we make a backup of resolv.conf
+	// and subsequently restore it. This is really ugly, and not safe if
+	// multiple tests do the same.
+	resolvconf, err := ioutil.ReadFile("/etc/resolv.conf")
+	if err != nil {
+		panic(fmt.Sprintf("Failed to read /etc/resolv.conf: %v", err))
+	}
+	type testCase struct {
+		Name    string
+		NetConf *NetConf
+	}
+	testCases := []testCase{
+		{
+			Name: "just IP addr",
+			NetConf: &NetConf{
+				Addresses: []AddrConf{
+					AddrConf{IPNet: net.IPNet{IP: net.ParseIP("10.20.30.40")}},
+				},
+			},
+		},
+		{
+			Name: "IP addr, DNS, and routers",
+			NetConf: &NetConf{
+				Addresses: []AddrConf{
+					AddrConf{IPNet: net.IPNet{IP: net.ParseIP("10.20.30.40")}},
+				},
+				DNSServers:    []net.IP{net.ParseIP("8.8.8.8")},
+				DNSSearchList: []string{"slackware.it"},
+				Routers:       []net.IP{net.ParseIP("10.20.30.254")},
+			},
 		},
 	}
-	err := ConfigureInterface(ifname, &nc)
-	require.NoError(t, err)
-}
+	for _, tc := range testCases {
+		t.Run(tc.Name, func(t *testing.T) {
+			require.NoError(t, ConfigureInterface(ifname, tc.NetConf))
 
-func TestConfigureInterfaceWithRouteAndDNS(t *testing.T) {
-	nc := NetConf{
-		Addresses: []AddrConf{
-			AddrConf{IPNet: net.IPNet{IP: net.ParseIP("10.20.30.40")}},
-		},
-		DNSServers:    []net.IP{net.ParseIP("8.8.8.8")},
-		DNSSearchList: []string{"slackware.it"},
-		Routers:       []net.IP{net.ParseIP("10.20.30.254")},
+			// after the test, restore the content of /etc/resolv.conf . The permissions
+			// are used only if it didn't exist.
+			if err = ioutil.WriteFile("/etc/resolv.conf", resolvconf, 0644); err != nil {
+				panic(fmt.Sprintf("Failed to restore /etc/resolv.conf: %v", err))
+			}
+			log.Printf("Restored /etc/resolv.conf")
+		})
 	}
-	err := ConfigureInterface(ifname, &nc)
-	require.NoError(t, err)
 }