Hi Gertrjan
thank you for replying, what you suggest would work i'm sure, but we have a policy where management of all assets is done on a specific Vlan (Vlan 20).
Unfortunately, I am unable to change that, policy, but as it happens, I resolved the issue earlier today, only just got home to update with the soultion.
I actually had done everythig correctly in pfSense, the problem was the guy who had set up the Cisco 3560, had applied all the three vlans to the trunk port as I had requested him to do, but he also had in the Cisco interface config the line 'switchport native vlan 20'.
I got him to remove this line and everything now works, so i've spent this afternoon setting up firewall rules blocking access to the and from the opt 1 vlan from the lan and wan for security, and blocking access to the management interface from the WAN and LAN interfaces too.
Tomorrow will be the big test day, but I quickly checked everything before I left and it seems to work perfectly, only access the webgui and ssh from vlan 20 and nowhere else.
Thank you again for the suggestion
Regards
Tony.