Found some answers
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/sw/11_x/licensing/cisco_dcnm_licensing_guide_11_x.html#concept_143D1BDEED9845A8A758A7D331619FF4
Cisco DCNM-SAN Client with Licensed Fabric
The following table displays the Cisco DCNM-SAN Client features that work with licensed fabric with a minimum of one licensed switch on the fabric.
Feature Licensed Fabric Unlicensed Fabric
Multiple client open sessions Y N
Multiple fabric open Y N
Remote client session Y N
Show Path Y N
Single fabric opened locally to DCNM server, as only client session
Y Y
IOA Y N
Table 8. Cisco DCNM-SAN Client Features
Which means
• If you are using a remote Cisco DCNM SAN client, you will not be able to open any unlicensed fabric. The fabric needs to be licensed, and therefore the Cisco DCNM Essential license will not work.
• If you are trying to open an unlicensed fabric from SAN client running on the Cisco DCNM server, you will be able to open only one unlicensed fabric at a time.
Therefore, if we must have a minimum of 2 advanced licenses (one per fabric)
DCNM-SAN-M93-K9 MDS 9300 DCNM SAN Adv. Feat. for MDS 9300