Icinga2 'fix'

diff --git a/doc/6-object-types.md b/doc/6-object-types.md
index b0779e8..822270d 100644
--- a/doc/6-object-types.md
+++ b/doc/6-object-types.md
@@ -908,6 +908,45 @@ Configuration Attributes:
   flush_interval         | **Optional.** How long to buffer data points before transfering to InfluxDB. Defaults to `10s`
   flush_threshold        | **Optional.** How many data points to buffer before forcing a transfer to InfluxDB.  Defaults 
 
+### <a id="objecttype-influxdbwriter-instance-tags"></a> Instance Tagging
+
+Consider the following service check:
+
+    apply Service for (disk => attributes in host.vars.disks) {
+      import "generic-service"
+      check_command = "disk"
+      display_name = "Disk " + disk
+      vars.disk_partitions = disk
+      assign where host.vars.disks
+    }
+
+This is a typical pattern for checking individual disks, NICs, SSL certificates etc associated
+with a host.  What would be useful is to have the data points tagged with the specific instance
+for that check.  This would allow you to query time series data for a check on a host and for a
+specific instance e.g. /dev/sda.  To do this quite simply add the instance to the service variables:
+
+    apply Service for (disk => attributes in host.vars.disks) {
+      ...
+      vars.instance = disk
+      ...
+    }
+
+Then modify your writer configuration to add this tag to your data points if the instance variable
+is associated with the service:
+
+    object InfluxdbWriter "influxdb" {
+      ...
+      service_template = {
+        measurement = "$service.check_command$"
+        tags = {
+          hostname = "$host.name$"
+          service = "$service.name$"
+          instance = "$service.vars.instance$"
+        }
+      }
+      ...
+    }
+