Hi,
This is R81.10. It has default configuration, so if Log Indexing is disabled by default, it is disabled. I saw this in the documentation:
Enabling Log Indexing
Log indexing on the Security Management ServerClosed or Log ServerClosed reduces the time it takes to run a query on the logs. Log indexing is enabled by default.
In a standaloneClosed deployment, log indexing is disabled by default. Enable log indexing only if the standalone server CPU has 4 or more cores.
So, a little bit ambiguous. I checked and it was disabled. I have enabled and now ir working as expected.
Thank you very much,
Julián