diff --git a/docs/content/manual/release-specific/v1.6.0/test-upgrade-responder-collectiing-average-sizes-for-v1-volumes-only.md b/docs/content/manual/release-specific/v1.6.0/test-upgrade-responder-collectiing-average-sizes-for-v1-volumes-only.md
new file mode 100644
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+++ b/docs/content/manual/release-specific/v1.6.0/test-upgrade-responder-collectiing-average-sizes-for-v1-volumes-only.md
@@ -0,0 +1,81 @@
+---
+Test upgrade-responder: Collecting Average Sizes for V1 Volumes Only
+---
+
+## Related issues
+
+- https://github.com/longhorn/longhorn/issues/7380
+
+## Test step
+
+**Given** Patch build and deploy Longhorn.
+```
+diff --git a/controller/setting_controller.go b/controller/setting_controller.go
+index de77b7246..ac6263ac5 100644
+--- a/controller/setting_controller.go
++++ b/controller/setting_controller.go
+@@ -49,7 +49,7 @@ const (
+ var (
+ 	upgradeCheckInterval          = time.Hour
+ 	settingControllerResyncPeriod = time.Hour
+-	checkUpgradeURL               = "https://longhorn-upgrade-responder.rancher.io/v1/checkupgrade"
++	checkUpgradeURL               = "http://longhorn-upgrade-responder.default.svc.cluster.local:8314/v1/checkupgrade"
+ )
+
+ type SettingController struct {
+```
+> Match the checkUpgradeURL with the application name: `http://<APP_NAME>-upgrade-responder.default.svc.cluster.local:8314/v1/checkupgrade`
+
+**And** setting `v2-data-engine` value is `true`.  
+**And** add a block disk to cluster nodes.  
+**And** [deploy upgrade responder stack](https://github.com/longhorn/longhorn/tree/master/dev/upgrade-responder).  
+
+**When** create 50 mi volume `lhv-v1` using v1 data engine.  
+**And** create 50 mi volume `lhv-v2` using v2 data engine.  
+**And** attach volume `lhv-v1` and write some data.  
+**And** attach volume `lhv-v2` and write some data.  
+**And** Wait 1~2 hours for collection data to send to the influxDB database.  
+
+**Then** the value of field `longhorn_volume_average_size_bytes` in the influxdb should equal to the average size of all v1 volumes (excluding v2 volumes).  
+**And** the value of field `longhorn_volume_average_actual_size_bytes` in the influxdb should be equal or simular to the average actual size of all v1 volumes (excluding v2 volumes).  
+> It's OK for the actual size to be slightly off due to ongoing workload activities, such as data writing by the upgrade-responder.  
+```bash
+# Get the sizes in the influxdb.
+#
+# Sample:
+# > name: upgrade_request
+#   time                longhorn_volume_average_actual_size_bytes longhorn_volume_average_size_bytes
+#   ----                ----------------------------------------- ----------------------------------
+#   1703045996398941914 73269248                                  1449132032
+#   1703046063248379696 73284266                                  1449132032
+app_name="longhorn"
+influxdb_pod=$(kubectl get pod | grep influxdb | awk '{print $1}' | head -n 1)
+kubectl exec -it ${influxdb_pod} -- influx -execute 'SELECT "longhorn_volume_average_actual_size_bytes", "longhorn_volume_average_size_bytes" FROM "upgrade_request"' -database="${app_name}_upgrade_responder"
+```
+
+```bash
+# Get the sizes from Longhorn volumes.
+
+v1_volume_count=$(kubectl get volumes -n longhorn-system -o=jsonpath='{range .items[*]}{.spec.backendStoreDriver}{"\n"}{end}' | grep -c 'v1')
+echo "Number of V1 volumes: $v1_volume_count"
+
+# Get the expected average size.
+# > Total size: 4347396096
+# > Average size: 1449132032
+total_size=$(kubectl get volumes -n longhorn-system -o=json | jq -r '[.items[] | select(.spec.backendStoreDriver != "v2") | .spec.size | tonumber] | add')
+echo "Total size: $total_size"
+
+average_size=$(echo "scale=0; $total_size / $v1_volume_count" | bc)
+echo "Average size: $average_size"
+
+# Get the expected average actual size.
+#
+# Sample:
+# > Total actualSize: 220368896
+# > Average actual size: 73456298
+total_actual_size=$(kubectl get volumes -n longhorn-system -o=json | jq -r '[.items[] | select(.spec.backendStoreDriver != "v2") | .status.actualSize | tonumber] | add')
+echo "Total actualSize: $total_actual_size"
+
+average_total_actual_size=$(echo "scale=0; $total_actual_size / $v1_volume_count" | bc)
+echo "Average actual size: $average_total_actual_size"
+```