Better handling of ifb0 (#93)

* Better handling of ifb0

* fix

* fix

lib/tc.js

@@ -21,19 +21,23 @@ async function getDefaultInterface() {
 async function moduleProbe() {
   try {
     await sudo('modprobe', 'ifb');
+    // eslint-disable-next-line no-empty
+  } catch {}
+}
+async function setupifb0() {
+  try {
+    // Check if ifb0 exist
+    await sudo('ip', 'link', 'show', 'ifb0');
   } catch {
-    // we are probably in a Docker env
-    // let us hope that the host is Linux
-    try {
-      await sudo('ip', 'link', 'add', 'ifb0', 'type', 'ifb');
-    } catch {
-      // If we already setup ifb in a previous run, this will fail
-    }
+    // Add the interface
+    await sudo('ip', 'link', 'add', 'ifb0', 'type', 'ifb');
   }
+
+  // Bring the interface up
+  await sudo('ip', 'link', 'set', 'ifb0', 'up');
 }
 
 async function setup(defaultInterface) {
-  await sudo('ip', 'link', 'set', 'dev', 'ifb0', 'up');
   await sudo('tc', 'qdisc', 'add', 'dev', defaultInterface, 'ingress');
   await sudo(
     'tc',
@@ -145,6 +149,7 @@ export async function start(up, down, rtt = 0, packetLoss = 0) {
 
   const indexFace = await getDefaultInterface();
   await moduleProbe();
+  await setupifb0();
   await setup(indexFace);
   await setLimits(up, down, halfWayRTT, packetLoss, indexFace);
 }