I'm unsure which NSX cert(VCP,VCAP,VCDX) you are referring . For the list of trainings and certification please do check below links
Certification
NSX Cert links ->Certification
Training Courses -> VMware NSX Training and Certification
For eg: if you are interested in NSX-VCP tracks there are few prerequisites(Without any other valid VCP certs) , either you can attend a VMware official training listed under VCP tracks or Submit proof that you hold a qualifying Cisco CCNA, CCNP or CCIE certification
VMware Certified Professional 6 – Network Virtualization (VCP6-NV)
Note : There are no more VCA NV-DCV tracks
Cheers,
Sree | VCIX-5X| VCAP-5X| VExpert 6x|Cisco Certified Specialist
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