Hi,
I connect my Fortinet Physical Port 1 to DGS Port 24 (Fortinet Physical port couldn't find Vlan Option) (Fortinet physical interface address - 192.168.1.1/24)
...
I keep the port 24 of DGS in Hybrid mode
Choosing this configuration (which is in contrast to my suggestion to use 2 subinterfaces at your Fortinet and leave Fortinet Physical Port 1 unconfigured for IP), please ensure that hybrid mode for DGS port 24 is configured as follows: L2 Features > VLAN > VLAN Interface > VLAN Detail (for selected port 24):
VLAN Mode: Hybrid
Native VLAN: 4
Hybrid Untagged VLAN: 4
Hyprid Tagged VLAN: 2
Alternatively (and this is what I would prefer) according to my suggestion do not configure IP for the physical port 1 of your Fortinet firewall. Instead create a second subinterface and configure this subinterface for your admin network (192.168.1.1/24) to send and receive frames tagged with VID 4.
If you follow this alternative, configure port 24 of your DGS to be in Trunk mode with Action=Tagged and Allowed VLAN Range=2,4.
DGS port 1 should be set to VLAN Mode "Access" with "Acceptable Frame" set to "Untagged only" and the VID set to 2.
DGS port 23 should be set to VLAN Mode "Access" with "Acceptable Frame" set to "Untagged only" and the VID set to 4.
Set any other port you want to use for your security network the same way as DGS port 1.
Set any other port you want exclusively use for your admin network the same way as DGS port 23.
Configure the two ports connected to your access points to be in Trunk Mode with Action=Tagged and Allowed VLAN Range=3,4.
Modify the configuration of port 24 of your DGS to be in Trunk mode with Action=Tagged and Allowed VLAN Range=2,3,4.
Create a third subinterface for your Fortinet phyical interface 1 and configure this subinterface for your guest network (192.168.3.1/24) to send and receive frames tagged with VID 3.
VLAN 4 - Can a specific device in VLAN for me associated to a Management VLAN, ie: VLAN 1 so that device can access everything for management reason?
You could choose a device that supports both Wifi and wired network using Wifi to connect to VLAN 4 and using a NIC to connect to VLAN 1 (ie: any default DGS port assigned to VLAN 1). Or you use a device that supports VLAN trunks for a NIC (Linux or with Windows, if the NIC driver supports it), that you connect to a DGS port set to mode Trunk with Action=Tagged and Allowed VLAN Range=1,4.
Or you choose to change the default management VLAN for your DGS to be 4 instead of 1 (this way allowing any device within your admin VLAN 4 to access the DGS management interface). But be careful: If you change the management vlan of your switch, you also must assign it a management address out of range 192.168.1.0/24, otherwise you will lose the management access to your switch if you do things in the wrong sequence (and you have to reset it to fabric defaults for recovery). See the manual what the correct procedure is for changing the switch's management vlan and address.
Finally (and I would prefer this) you could also generate a fourth subinterface for your Fortinet physical port 1, assign it an IP address out of the range of the DGS management VLAN 1 and configure it to send and receive frames tagged with VLAN 1. In addition modify the configuration of port 24 of your DGS to be in Trunk mode with Action=Tagged and Allowed VLAN Range=1,2,3,4. The last step is a Fortinet firewall rule that only allows a specific admin device in VLAN 4 (your management device 192.168.1.x) to access the DGS management address in VLAN 1. To make it perfect you should remove any unused DGS port from VLAN 1 to prevent any unauthorized access to vlan 1 by any device plugged to a free port.
PT