Different proxy for different interfaces
Is there any option, or is it even possible in theory to use a different proxy server for different interfaces?
For example: I have a LAN interface which is not using any proxy whatsoever, but I have another interface (OPT1) and I want any traffic happening on that specific interface to use a proxy server.
Is there any options to achieve this, or it's not even possible?
You can set Squid to listen on specific interfaces only. Ir redirect to it on only some interfaces.
What you can't do is have it behave differently just on the basis of interfaces. You can filter on different subnets though.
What exactly are you trying to achieve?
I'm trying to have multiple VLAN's with different proxy servers
LAN: No proxy at all
OPT1 (VLAN 60): http proxy 188.8.131.52:9091
OPT2 (VLAN 31): socks proxy 10.10.10.10:9050 (another question is if there is support for socks)
OPT3 (VLAN 90): http proxy 184.108.40.206:9091
So the main goal would be a scenario with 3 managed switches carrying one of the three VLAN tags, and each host connected to it's corresponding switch would have it's proxy "set up" right away.
Host A and B would like to use proxy 220.127.116.11:9091
Host C want to have 18.104.22.168:9091 as it's proxy
Host D wants 10.10.10.10:9050
So I connect A and B to a switch that has two ports set up in vlan60
C will have a port in vlan31, and D in vlan90
And you want the proxies to behave differently?
You can only run a single Squid instance on pfSense itself.
I have all the proxy servers ready and on my network, I just want pfsense subnets (or interfaces) to use different ones. I know I can set up one globally, but I need like 3 and on different subnets/vlans
So you just need to redirect traffic to them in pfSense? You can just use port forwards for that. That's what Squid does if you set it to transparent mode.