Configuring FortiSwitch split ports (phy-mode) in FortiLink mode

On FortiSwitch models that provide 40G/100G QSFP (quad small form-factor pluggable) interfaces, you can install a breakout cable to convert one 40G/100G interface into four 10G/25G interfaces. See the list of supported FortiSwitch models in the notes in this section.

FortiLink mode supports the FortiSwitch split-port configuration:

• Configuring split ports on a previously discovered FortiSwitch unit
• Configuring split ports with a new FortiSwitch unit
• Configuring forward error correction on switch ports
• Configuring a split port on the FortiSwitch unit

Notes

• Split ports are not configured for pre-configured FortiSwitch units.
• Splitting ports is supported on the following FortiSwitch models:
  • FS-3032D (ports 5 to 28 are splittable)
  • FS-3032E (Ports can be split into 4 x 25G when configured in 100G QSFP28 mode or can be split into 4 x 10G when configured in 40G QSFP mode. Use the set <port_name>-phy-mode disabled command to disable some 100G ports to allow up to sixty-two 100G/25G/10G ports.)
  • FS-524D and FS-524D-FPOE (ports 29 and 30 are splittable)
  • FS-548D and FS-548D-FPOE (ports 53 and 54 are splittable)

  • FS-1048E—In the 4 x 100G configuration, ports 49, 50, 51, and 52 are splittable as 4 x 25G, 4 x 10G, 4 x 1G, or 2 x 50G. Only two of the available ports can be split.

  • FS-1048E—In the 4 x 4 x 25G configuration, ports 49, 50, 51, and 52 are splittable as 4 x 4 x 25G or 2 x 50G. All four ports can be split, but ports 47 and 48 are disabled.

  • FS-1048E—In the 6 x 40G configuration, ports 49, 50, 51, 52, 53, 54 are splittable as 4 x 10G or 4 x 1G.

  • FS-T1024E—Ports 25 and 26 have a maximum speed of 100G; each port can be split into four subports of 25G or 10G.

  • FS-1024E—Ports 25 and 26 have a maximum speed of 100G; each port can be split into four subports of 25G or 10G.

  Use the set port-configuration ? command to check which ports are supported for each model.

• Currently, the maximum number of ports supported in software is 64 (including the management port). Therefore, only 10 QSFP ports can be split. This limitation applies to all of the models, but only the FS-3032D, FS-3032E, and the FS-1048E models have enough ports to encounter this limit.
• Use 10000full for the general 10G interface configuration. If that setting does not work, use 10000cr for copper connections (with copper cables such as 10GBASE-CR) or use 10000sr for fiber connections (fiber optic transceivers such as 10GBASE-SR/-LR/-ER/-ZR).
• Starting in FortiOS 7.2.0 and FortiSwitchOS 7.2.0, the FortiGate device automatically updates the port list after split ports are changed and the FortiSwitch unit restarts. When split ports are added or removed, the changes are logged.

Configuring split ports on a previously discovered FortiSwitch unit

Using FortiLink mode over a layer-3 network requires both FortiOS 7.2.x (and later) and FortiSwitchOS 7.2.x (and later).

Before FortiOS 7.2.0:

1. On the FortiSwitch unit, configure the split ports. See Configuring a split port on the FortiSwitch unit.
2. Restart the FortiSwitch unit.
3. Remove the FortiSwitch from being managed:

   config switch-controller managed-switch

   delete <FortiSwitch_serial_number>

   end

4. Discover the FortiSwitch unit.
5. Authorize the FortiSwitch unit.

Starting with FortiOS 7.2.0:

1. On the FortiSwitch unit, configure the split ports. See Configuring a split port on the FortiSwitch unit.
2. Restart the FortiSwitch unit.

Configuring split ports with a new FortiSwitch unit

Using FortiLink mode over a layer-3 network requires both FortiOS 7.2.x (and later) and FortiSwitchOS 7.2.x (and later).

Before FortiOS 7.2.0:

1. Discover the FortiSwitch unit.
2. Authorize the FortiSwitch unit.
3. On the FortiSwitch unit, configure the split ports. See Configuring a split port on the FortiSwitch unit.
4. Restart the FortiSwitch unit.
5. Remove the FortiSwitch from being managed:

   config switch-controller managed-switch

   delete <FortiSwitch_serial_number>

   end

6. Discover the FortiSwitch unit.
7. Authorize the FortiSwitch unit.

Starting with FortiOS 7.2.0:

1. Discover the FortiSwitch unit.
2. Authorize the FortiSwitch unit.
3. On the FortiSwitch unit, configure the split ports. See Configuring a split port on the FortiSwitch unit.
4. Restart the FortiSwitch unit.

Configuring forward error correction on switch ports

Supported managed-switch ports of the FS-1048E and FS-3032E can be configured with a forward error correction (FEC) state of Clause 74 FC-FEC for 25-Gbps ports and Clause 91 RS-FEC for 100-Gbps ports.

Starting in FortiOS 7.4.2, when a FortiSwitch unit is capable of FEC, the default setting for fec-state is detect-by-module, which automatically detects whether FEC is supported by the module.

config switch-controller managed-switch
	edit <FortiSwitch_serial_number>
		config ports
			edit <port_name>
				set fec-capable {0 | 1}
				set fec-state {cl74 | cl91 | detect-by-module | disabled}
			next
		end
	next
end

fec-capable {0 | 1}

Set whether the port is FEC capable. 0: The port is not FEC capable. 1: The port is FEC capable.

fec-state {cl74 | cl91 | detect-by-module | disabled}

Set the FEC state: c174: Enable Clause 74 FC-FEC. This option is only available for on FS-1048E, FS-3032E, FS-1024E, and FS-T1024E ports that have been split to 4x25G. c191: Enable Clause 91 RS-FEC. This option is only available for on FS-1048E and FS-3032E ports that have been split to 4x100G. detect-by-module: Automatically detect whether FEC is supported by the module. disabled: Disable FEC on the port.

In this example, a FortiSwitch FS-3032E that is managed by a FortiGate device is configured with Clause 74 FC-FEC on port 16.1 and Clause 91 RS-FEC on port 8.

config switch-controller managed-switch
	edit FS3E32T419000000
		config ports
			edit port16.1
				set fec-state cl74
			next
			edit port8
				set fec-state cl91
			next
		end
	next
end

Configuring a split port on the FortiSwitch unit

To configure a split port:

config switch phy-mode

set port-configuration <default | disable-port54 | disable-port41-48 | 4x100G | 6x40G | 4x4x25G}

set {<port-name>-phy-mode <single-port| 4x25G | 4x10G | 4x1G | 2x50G}

...

(one entry for each port that supports split port)

end

The following settings are available:

• disable-port54—For 548D and 548D-FPOE, only port53 is splittable; port54 is unavailable.
• disable-port41-48—For 548D and 548D-FPOE, port41 to port48 are unavailable, but you can configure port53 and port54 in split-mode.
• 4x100G—For 1048E, enable the maximum speed (100G) of ports 49 through 52. Ports 53 and 54 are disabled.
• 6x40G—For 1048E, enable the maximum speed (40G) of ports 49 through 54.
• 4x4x25G—For 1048E, enable the maximum speed (100G) of ports 49 through 52; each split port has a maximum speed of 25G. Ports 47 and 48 are disabled.
• single-port—Use the port at the full base speed without splitting it.
• 4x25G—For 100G QSFP only, split one port into four subports of 25 Gbps each.

  NOTE: For the FS-T1024E and FS-1024E models, the auto-module selects the correct speed for the subports. If you insert a 100G QSFP28 module, the subports are automatically changed to 4x25G. If you insert a 40G QSFP+ module, the subports are automatically changed to 4x10G.

• 4x10G—For 40G or 100G QSFP only, split one port into four subports of 10Gbps each.
• 4x1G—For 40G or 100G QSFP only, split one port into four subports of 1 Gbps each.
• 2x50G—For 100G QSFP only, split one port into two subports of 50 Gbps each.

In the following example, a FortiSwitch 524D is configured with port29 set to 4x10G:

config switch phy-mode

set port29-phy-mode 4x10G

end

The system applies the configuration only after you enter the end command, displaying the following message:

This change will cause a ports to be added and removed, this will cause loss of configuration on removed ports. The system will have to reboot to apply this change.

Do you want to continue? (y/n)y

To configure one of the split ports, use the notation ".x" to specify the split port:

config switch physical-port

edit "port1"

set lldp-profile "default-auto-isl"

set speed auto

next

edit "port2"

set lldp-profile "default-auto-isl"

set speed auto

next

.

.

.

edit "port29.1"

set lldp-profile "default-auto-isl"

set speed auto-module

next

edit "port29.2"

set lldp-profile "default-auto-isl"

set speed auto-module

next

edit "port29.3"

set lldp-profile "default-auto-isl"

set speed auto-module

next

edit "port29.4"

set lldp-profile "default-auto-isl"

set speed auto-module

next

edit "port30"

set lldp-profile "default-auto-isl"

set speed auto-module

next

end