diff --git a/openvpn.py b/openvpn.py
index 5ac06e4..bbaf964 100644
--- a/openvpn.py
+++ b/openvpn.py
@@ -160,9 +160,10 @@ class Openvpn:
         assert self.interface in io_count, "cannot find interface, nic is not there"
         io_count = io_count[self.interface]
         open(self.io_stat_fp, "a").write(
-            f"{datetime.utcnow().timestamp()},{io_count.bytes_recv},{io_count.bytes_recv}\n")
+            f"{datetime.utcnow().timestamp()},{io_count.bytes_recv},{io_count.bytes_sent}\n")
         #command = ["ping", "-w", "1", "-c", "1", "8.8.8.8"]
-        command = ["fping", "-C", "1", "-t200", "-q", "8.8.8.8"]
+        command = ["fping", "-C", "1", "-t200",
+                   "-I", self.interface, "-q", "8.8.8.8"]
         p = subprocess.Popen(
             command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
         result = p.communicate()