Dell PowerEdge FN I/O Module Configuration Guide 9.10(0.0)

You can enable the option to access and administer an Aggregator only using the chassis management controller (CMC) interface, and prevent the usage of the CLI interface of the device to configure and monitor settings. You can configure the restrict-access session command to disable access of the Aggregator using a Telnet or SSH session; the device is accessible only using the CMC GUI. You can use the no version of this command to reactivate the Telnet or SSH session capability for the device. Use the show restrict-access command to view whether the access to a device using Telnet or SSH is disabled or not.