It's Linux based system but its shell is limited to some maintenance commands specific to product. There are also some limited number of Linux commands available - like ifconfig, route, ping, telnet.
But when it's not enough, when you need access some additional logs, there is a support user with access to full Linux shell.
Here is a receipt how to access this account.
- Open a console (on pictures Virtual Machine Console is launched under VMware vShpere Client).
- Login as admin with your admin password.
- Run set-support command and set temporary password for support user (temporary but product asks for complex password).
- Logout (as admin).
- Login as support with temporary password.
- Enjoy your freedom.