docs: cleaning of docker VM on ovh2 (#250)

docs/logs-ovh2.md

@@ -1,4 +1,12 @@
 # ovh2 server logs
 
 Report here the timeline of incidents and interventions on ovh2 server.
-Keep things short or write a report.
+Keep things short or write a report.
+
+## 2023-09-04 cleaning docker monitoring VM
+
+In order to enable using off-query on staging (which will consume around 35G of data)
+* removed the `monitoring/` docker containers and volumes (docker-compose down -v) and the folder
+  as they were moved to their own container (see [2022-11 moving monitoring to its own machine](./reports/2022-11-09-monitoring-move-to-own-vm.md))
+* `docker volume prune`  reclaimed space.
+* from 76G (out of 294) of free space we are back to 118G.