If you need to keep empty tiers of your APM application from being purged, there is a way to do so in controllers v.22.10 and above.
To do this:
- Navigate to the Tiers & Nodes page
- Select a tier and then click on the "Details" button above
- On the next view click the drop-down button "Actions" in the upper-right corner
- Then select the option "Edit Properties"
In the opened modal window edit the field "Description" - you can use any description you want, but it must contain the pattern "NON_PURGEABLE_TIER"
Finally, save changes. The empty tier won't be purged (manual purging is still available if needed).
