Hello Ruben,
Ben from Zerto Support here.
There is no mention of NetScaler in Zerto's Interoperability Matrix:
https://help.zerto.com/bundle/Zerto_Interoperability_Matrix/resource/Zerto_Interoperability_Matrix.pdf
There is also no documentation on this.
If you can please open a support case on NetScaler compatibility, our team will investigate further and get back to you.
More info on opening support cases can be found in this article:
https://help.zerto.com/kb/000004662
Thank you.
Ben N.
