Ruben,
Is your question how to factory reset the Nexus 7000 itself? If so, the process is simple:
switch# write erase
Warning: This command will erase the startup-configuration.
Do you wish to proceed anyway? (y/n) [n] y
switch# reload
This command will reboot the system. (y/n)? [n] y
...
Enter the password for "admin": <password>
Confirm the password for "admin": <password>
...
Would you like to enter the basic configuration
dialog (yes/no): n
switch#
This is documented in the Nexus 7000 NX-OS Fundamentals Configuration Guide. Please note that the `write erase` command will essentially delete the startup configuration, and once the device reloads, it will come back as a new switch. Be sure to back up any configurations you want to keep for review later.
I hope that helps!
- Andrea, CCIE #56739 R&S