[squid-users] Shared cache directory.

[Amos Jeffries]

On 24/06/17 04:05, Eduardo Carneiro wrote:
> Hi everyone.
> 
> Squid version 3.5.19.
> 
> I need to set up a load balancing. It would be something like, 3 servers
> decentralizing the accesses. I already have that solution.
> 
> But when I decentralize the cache directories, my "HIT rates" decrease.

Correct.


> 
> I'd like to know if there is any way to have more than one squid server
> sharing the same cache directory.

Not in the way you seem to be thinking of.


> 
> I have already tried it using cache_peer, with "follow_x_forwarded_for"
> function to do this. But, due to the use of ssl_bump, this solution did not
> answer me because, in https requests, the client IP was not shown.

Doing SSL-Bump effectively requires that the proxy terminating the TLS 
be the one caching. Passing the traffic in to a peer has major problems 
with cert mimic'ing.


If you are intercepting port 443, you should be able to LB by 
destination-IP to maximize the hit ratio.

That implies a traditional CARP cache_peer installation which is the 
solution for this problem in plain-HTTP should work almost as well for 
HTTPS. Just do the CARP based on destination-IP for the fake CONNECT 
requests the 'intercept' https_port generates - and put SSL-Bump in the 
backends which are caching.


Amos