Items under the Diagnostics menu perform various diagnostic and administrative tasks.

ARP Table:Displays a list of devices as seen locally by the firewall. The list includes an IP address, MAC address, Hostname, the Interface where the device was seen, and other related information.
Authentication:Tests authentication to a defined RADIUS or LDAP server. See Troubleshooting.
Backup & Restore:
 Backup and restore configuration files. See Backup and Recovery.
Command Prompt:Execute shell commands or PHP code, and upload/download files to/from the firewall. Use with caution.
DNS Lookup:Executes a DNS lookup to resolve hostnames for diagnostic purposes, and to test connectivity to DNS servers. See Testing DNS.
Edit File:Edit a file on the firewall filesystem.
Factory defaults:
 Resets the configuration back to default. Be aware, however, that this does not alter the filesystem or uninstall package files; it only changes configuration settings. See Reset to factory defaults.
GEOM Mirrors:If the firewall contains a GEOM disk mirror, this page shows the status of the mirror and provides controls for managing the mirror.
Halt system:Shuts down the firewall and turns off the power where possible. See Halt system.
Limiter Info:Shows the status of any Limiters and the traffic flowing inside them. See Checking Limiter Usage.
NDP Table:Shows a list of local IPv6 devices as seen by the firewall. The list includes an IPv6 address, MAC address, hostname (if known to the firewall), and the interface.
Packet Capture:Perform a packet capture to inspect traffic, and then view or download the results. See Packet Captures from the WebGUI.
pfInfo:Displays statistics about the packet filter, including general traffic rates, connection rates, state table info, and various other counters. See pfInfo.
pfTop:Displays a list of the top active connections by a selectable metric such as bytes, rate, age, etc. See Viewing States with pfTop.
Ping:Sends ICMP echo requests to a given IP address, sent via a chosen interface.
Reboot system:Reboots the firewall. This can take several minute to complete, depending on the hardware and enabled features. See Reboot system.
Routes:Shows the contents of the routing table. See Viewing Routes.
SMART Status:Displays diagnostic information about disk drives, if supported by the hardware. Can also run drive tests. See S.M.A.R.T. Hard Disk Status.
Sockets:Displays a list of processes on the firewall that are bound to network ports, listening for connections or making connections outbound from the firewall itself.
States:Shows the currently active firewall states. See Firewall States.
States Summary:Displays information about the state table, to see activity summarized by IP address. See States Summary.
System Activity:
 Shows memory usage and a list of active processes and system threads on the firewall, the output is from top -aSH . See System Activity (Top).
Tables:Displays and edits the contents of various firewall tables and aliases. See Viewing the Contents of Tables.
Test Port:Performs a simple TCP connection test from the firewall to determine if a remote host is accepting connections on a specified port.
Traceroute:Trace the route taken by packets between this firewall and a remote system. See Using traceroute.