Hi,
We are performing a rolling upgrade from ES6 to ES7 and we have 3 types of nodes:
- Coordinators
- Data-only
- Master eligible-only
As recommended, we start the upgrade with the non-master-eligible nodes, in our case the coordinator nodes.
Once the coordinator nodes are upgraded, we start seeing scroll responses containing -Infinity scores instead of the expected null.
This breaks golang clients because they can't parse that value, but we wanted to know why these -Infinity scores are appearing.
The same requests going directly to the data nodes have the expected null scores.
Sort is set to _doc and when we remove that, the scores no longer are shown as -Infinity.
Setting explain: true doesn't provide much information, as the explained scores look normal but the _score fields still display -Infinity.
Note that the upgrade is from 6.8.4 to 7.9.1, so at this point in time, the coordinator nodes are using 7.9.1 and the data nodes use 6.8.4.
Is this a known issue? Should we take a different upgrade approach?
Thanks,
Giorgos