diff --git a/CHANGELOG.md b/CHANGELOG.md
index 56058b4d3..9e7fc92da 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 
 ### Bugfixes
 - [#506](https://github.com/influxdb/telegraf/pull/506): Ping input doesn't return response time metric when timeout. Thanks @titilambert!
+- [#508](https://github.com/influxdb/telegraf/pull/508): Fix prometheus cardinality issue with the `net` plugin
 
 ## v0.10.0 [2014-01-12]
 
diff --git a/plugins/inputs/system/net.go b/plugins/inputs/system/net.go
index 95df7a741..42f0d5854 100644
--- a/plugins/inputs/system/net.go
+++ b/plugins/inputs/system/net.go
@@ -94,7 +94,10 @@ func (s *NetIOStats) Gather(acc inputs.Accumulator) error {
 			fields[name] = value
 		}
 	}
-	acc.AddFields("net", fields, nil)
+	tags := map[string]string{
+		"interface": "all",
+	}
+	acc.AddFields("net", fields, tags)
 
 	return nil
 }
diff --git a/plugins/inputs/system/net_test.go b/plugins/inputs/system/net_test.go
index ba71848d1..3ec2cb990 100644
--- a/plugins/inputs/system/net_test.go
+++ b/plugins/inputs/system/net_test.go
@@ -80,7 +80,10 @@ func TestNetStats(t *testing.T) {
 		"udp_noports":     int64(892592),
 		"udp_indatagrams": int64(4655),
 	}
-	acc.AssertContainsTaggedFields(t, "net", fields2, make(map[string]string))
+	ntags = map[string]string{
+		"interface": "all",
+	}
+	acc.AssertContainsTaggedFields(t, "net", fields2, ntags)
 
 	acc.Points = nil