diff --git a/etc/telegraf.conf b/etc/telegraf.conf
index ec5469ae0e683..1df63db053794 100644
--- a/etc/telegraf.conf
+++ b/etc/telegraf.conf
@@ -1641,6 +1641,11 @@
 #   ## stay in order set this to true.  keeping the metrics ordered may
 #   ## be slightly slower
 #   # ordered = false
+#
+#   ## cache_ttl is the amount of time interface names are cached for a
+#   ## given agent.  After this period elapses if names are needed they
+#   ## will be retrieved again.
+#   # cache_ttl = "8h"
 
 
 # # Apply metric modifications using override semantics.