I am going to ask someone if I can configure Mikrotik with external proxy Squid in Ubuntu.
Mikrotik has 3 interfaces: WAN, LAN1(clients), LAN2(squid)
Squid has 1 interface LAN
I want to know if I can configure Squid as transparnet proxy.
Can any one help me in this case, can I configure it or I must have two interfaces in squid?
have a look at this post:
http://forum.mikrotik.com/t/forward-traffic-to-dansguardian-machine/24068/2
If your network is 192.168.0.0/24, you can create 192.168.1.0/24 and put your squid box in there. After that, just forward outgoing HTTP to squid.
Thank you for your answer, I will try it but firstly I will see to configure Squid in Ubuntu and test it than I will configure rules in mikrotik, it was not clear for me if I must have two interfaces in squid as I see I can use it with one interface.
I will see for squid configuration.
Thank you very much for your answer
FreeBSD used to be the best choice for web proxy (squid).
I am using PPPoE Server on my mikrotik, any idea how could I configure squid to work in this case, any sugestions?
Thanks in advance
I have pretty much similar config to the setup but i used mangle-route mark instead of DST-NAT (it works both ways).
though I’m having trouble capturing the traffic from proxy using mangle rule + simple queues. 
I need help about how to implement external cache+transparent proxy in Mikrotik with 3 interfaces as in the picture, and PPPoE users, any one can help me what rules to create, any suggestions.
Thanks