Technical Tip: Management Protocols for FortiSwitch discovery on FortiGate

[sachitdas_FTNT]

Description	This article describes the Management/control plane protocols responsible for FortiSwitch discovery on FortiGate.
Scope	FortiSwitch Managed by FortiGate v7.x and above
Solution	Refer to the Managed FortiSwitch Guide for details: Whatʼs new in FortiOS 7.6.0 FortiGate uses multiple protocols to control FortiSwitch for discovery, and health checks: FortiLink: Default FortiSwitch discovery method, also used for heartbeats between FortiGate and FortiSwitch. The discovery frame includes the FortiSwitch Serial number and port information. Ethernet Type 0x88FF: Technical Tip: FortiLinkd process on FortiSwitch Alternate discovery method: LLDP, used for auto-isl Configuration (Switch stack): Troubleshooting Tip: Fortilink inter-switch link(ISL) trunk not forming automatically on FortiSwitch... CAPWAP (UDP port 5246): Used for FortiSwitch authentication, authorization, and health-checks by establishing a DTLS tunnel between FortiGate and FortiSwitch. Used to push firmware upgrades to FortiSwitch from FortiGate used to receive LLDP information from FortiSwitch on FortiGate, used to receive logs from FortiSwitch : Technical Tip: Managed FortiSwitch Capwap discovery process Other Protocols: DHCP: Management IP address assignment. FortiGate acts as a DHCP server for the FortiSwitch. FortiSwitch receives an IP address from the FortiGate FortiLink interface. DNS: Name resolution. NTP: FortiGate's FortiLink interface IP address acts as an NTP server for the FortiSwitch. FortiSwitch syncs its time with FortiGate time. Otherwise, CAPWAP DTLS will not be established between FortiSwitch and FortiGate. HTTPS: FortiGate uses HTTPS to push configuration to FortiSwitch, collect diagnostics, and FortiSwitch's default firmware upgrade method. FortiGate uses FortiSwitch Rest API to communicate with FortiSwitch. SSH: CLI connection tool on FortiGate GUI, used to SSH to FSW IP address from FortiSwitch.