Help needed: Replacing 3x switches with 1x partitioned (if possible) switch

[waxhead]

Hi,

Currently I have OPNsense set up with 4x deticated links for the following:

• 1x WAN for Internet access
• 1x LAN for private stuff
• 1x OPT1 for public stuff (webservers, etc...)
• 1x OPT2 for WIFI access , private/guest

LAN + OPT1 and OPT2 go to their own cheap 5 port switches which keeps the networks isolated quite well.

I recently got a bricked Netgear GS724Tv3 switch from the garbage at work and with some help from our nasty uncle Google I was able to de-brick it. This switchs has 24 ports and therefore have more than the 3 (switches) x 5 (ports) = 15 I have today - this should allow for plenty of spare ports for future setup/experiments.

I was hoping that I can replace my 3x switches with this 24 port switch since it fits cleaner in my rack and only require one power plug as well instead of the current mess with 3x power adapters and extra cabling.

I was hoping that I can somehow "partition" the switch to keep certain ports isolated from each other. From what I have learned recently VLANS is apparently the way to go, but there is a clear warning in opnsense that "Not all drivers/NICs support 802.1Q VLAN tagging properly. On cards that do not explicitly support it, VLAN tagging will still work, but the reduced MTU may cause problems. "

What sort of problems are we talking about here? corruption? complete failure? discarded packages?! How do I know if VLAN is supported or now - can I test it without creating a setup?! Do it need to be supported on everything or just one component of the networks such as OPNsense?!

I also discovered that my switch allow me to set up something called PVID which seems to be a "internal VLAN id" for the networks on the switch, but I don't understand if I need support for this on the other end somehow.

VLAN / PVID marked ports also have what I learned is called TAGGED, UNTAGGED and EXCLUDED. As I understand this the tagging/untagging bit only adds or removes a VLAN ID on the incomming/outgoing package.

As you probably have understood by now I am a complete imbecile when it comes to VLAN's and that sort of thing. I have heard about it , but I know nothing about it except from a few articles found around internet which is not very useful.

What I am trying to achieve is to simply have 3x isolated switches in one switch. E.g. set port 1-5 to network A, port 6-10 to network B, 11-15 to network C without possibility of interaction between those A,B,C's on the switch.

I would appreciate if someone can help point me in the right direction for what to read / what do do.