diff --git a/plugins/docker/docker_ b/plugins/docker/docker_
index 7bfe94dd..18328f04 100755
--- a/plugins/docker/docker_
+++ b/plugins/docker/docker_
@@ -260,14 +260,13 @@ def parallel_container_stats(client):
 
 def print_containers_cpu(client):
     for container, stats in parallel_container_stats(client):
-        cpu_count = len(stats["cpu_stats"]["cpu_usage"]["percpu_usage"])
         cpu_percent = 0.0
         cpu_delta = (float(stats["cpu_stats"]["cpu_usage"]["total_usage"])
                      - float(stats["precpu_stats"]["cpu_usage"]["total_usage"]))
         system_delta = (float(stats["cpu_stats"]["system_cpu_usage"])
                         - float(stats["precpu_stats"]["system_cpu_usage"]))
         if system_delta > 0.0:
-            cpu_percent = cpu_delta / system_delta * 100.0 * cpu_count
+            cpu_percent = cpu_delta / system_delta * 100.0 * os.cpu_count()
         print(container.name + '.value', cpu_percent)
         print(container.name + '.extinfo', container_attributes(container))
 
@@ -287,13 +286,13 @@ def print_containers_network(client):
             rx_bytes += data['rx_bytes']
         print(container.name + '_up.value', tx_bytes)
         print(container.name + '_down.value', rx_bytes)
-        print(container.name + '.extinfo', container_attributes(container))
+        print(container.name + '_up.extinfo', container_attributes(container))
 
 
 def volume_summary(volume):
     summary = f"{volume.short_id}"
     if volume.attrs['Labels']:
-        summary += " ({', '.join(volume.attrs['Labels'])})"
+        summary += f" ({', '.join(volume.attrs['Labels'])})"
     return summary