We still have running and no longer used vms (and maybe services). Let's investigate
what really needs to run and stop what's not needed (and stop then destroy those):
```
|------------------+---------+------------+---------------------------------------------------------------|
| node | status | new status | note |
|------------------+---------+------------+---------------------------------------------------------------|
| cassandra[01-06] | stopped | dropped | no longer required |
| mirror-test | running | dropped | no longer required [in terraform manifest] |
| dbreplica0 | running | dropped | softwareheritage db replication in azure (unused) |
| dbreplica1 | running | | replicated softwareheritage-indexer db (sole indexer db copy) |
| storage01 | running | | required but some services can be stopped |
| storage02 | stopped | dropped | no longer required |
| ns0 | running | | required: secondary azure dns |
| vangogh | running | | required: vault server |
| worker[01-13] | running | | indexer and cooker workers |
|------------------+---------+------------+---------------------------------------------------------------|
```