You just solved my problem, Stephan. I removed Bind in tinyproxy.conf and it works. Also I tried to Bind to eth0 (external) and it works too. So apparently Bind to eth1 (internal), which was my old config, is not correct. I thought if I Bind to eth1, it'll automatically forward to eth0. Thanks so much. The issue has been bothering me for a couple of days.