[squid-users] HTTPS proxy working in non-transparent mode, failing in transparent mode

[David Salisbury]

I've got an install of Squid that I'm trying to get running as an HTTP 
and HTTPS proxy.  I've got some Squid experience, but up to this point 
only using it as an HTTP proxy (transparent, in that case).

I've gotten the HTTPS portion of the proxy working, if I run it in 
non-transparent mode; the HTTP portion is working as well.  I've 
installed the appropriate CA cert on the client machine I'm testing 
with, and have pointed the browser of the client machine to the IP and 
port of the Squid proxy.  Both HTTP and HTTPS work well, and I can 
successfully use Squid's ACL functions to whitelist and blacklist 
certain sites.

BUT, my ultimate goal is transparent mode for the HTTP and HTTPS 
proxying, and as soon as put Squid in transparent mode and take off the 
proxy information of the browser, I start to get certificate errors on 
the HTTPS-based sites.  HTTP proxying still works fine, but the HTTPS 
proxying breaks.

Does anyone have any suggestions as to what to look for that may be 
causing that?  I don't understand what could break just switching 
between non-transparent and transparent modes.

-David