Background index creation is still workable?

[Fabio_Ramohitaj]

Hi @Nagarajan_Ponnusamy and welcome to the community!
In a replica set, you can create the index in the following way:

Rolling Index Builds on Replica Sets - MongoDB Manual v7.0

About your question, the answer is detailed here:

After 4.2, background createIndexes

Hi @Kim_Hakseon, Per the documentation page you linked, all index builds in MongoDB 4.2+ use an optimised build path and there is no longer an option for foreground or background builds. The background index build option will be ignored if specified. The new index build process does not have the extensive blocking behaviour that was a concern for foreground index builds in previous server releases. Index build performance in 4.2+ should be similar (or better) than before depending on whether…

Regards