Yosemite Spotlight on Client not index server shared folder

I've a Mac Mini Server (Yosemite server) where is located the folder: 'Studio'. This folder is shared in the same network.

I've a Client iMac (Yosemite) that access to that folder 'Studio' located on server.

Spotlight on Server is able to search in that folder. Sporlight on Client is NOT able to search in that folder.

I've run on Client terminal:

sudo mdutil -E /Volumes/Studio

And have this error:

/Volumes/Studio:
2015-02-14 11:53:22.017 mdutil[4611:159875] mdutil disabling Spotlight: /Volumes/Studio -> kMDConfigSearchLevelOff
Error: unable to perform operation.  (-403)
    Server search enabled.

Any hints?