Hi all,

Looking for a bit of help with Umbraco Indexes configuration and behaviour

Umbraco version 8.18.8

Current configuration:

<add key="Umbraco.Core.MainDom.Lock" value="SqlMainDomLock" />
<add key="Umbraco.Core.LocalTempStorage" value="EnvironmentTemp" />
<add key="Umbraco.Examine.LuceneDirectoryFactory" value="Examine.LuceneEngine.Directories.SyncTempEnvDirectoryFactory, Examine" />

Hosted in an Azure webapp, single instance ( not set up to scale out)

Release configuration:

1- The code gets deployed to a "deploy" slot, once warms up, it gets swapped to the master/prod slot.

Current behaviour

1- The indexes are built successfully on the deploy slot: 1.1 - via Kudu, I can see the indexes are built successfully in the file shared system C:\local\Temp\ExamineIndexes\e73dbeb4394557572da3f75621c11ada\742a4a04576b7beccb98f465f502dakda 1.2 and in the worker file system: C:\home\site\wwwroot\App_Data\TEMP\ExamineIndexes\External

2- Once the deploy slot swaps into the production slot, umbraco starts up and it leaves the following stamp in the logs: No last synced Id found, this generally means this is a new server/install. The server will build its caches and indexes, and then adjust its last synced Id to the latest found in the database and maintain cache updates based on that Id. which seems to trigger a full rebuild of indexes which causes performance issues during the process etc (large site / large volume of nodes). During this time, via the CMS, DocumentCount External index is sitting at 0 and gradually starts building up to the expected number.

3- Post Swap (and before Umbraco starts up) I have validated manually via Kudu that ExamineIndexes files have been swapped correctly into prod/main slot (both worker file system and shared file system)

The question I have is:

Is the post-swap behaviour I'm seeing "No last synced Id found" the expected behaviour? or should Umbraco be able to see that indexes have already been generated and not generate them again?

Any help would be appreciated. Thanks in advance!