====== Squid ======

[[wp>Squid_(software)|Squid]] is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. It reduces bandwidth and improves response times by caching and reusing frequently-requested web pages.

===== Installation =====

<code bash>
yum install squid

systemctl start squid
</code>

===== HTTP basic authenication =====

<code bash>
touch /etc/squid/passwd && chown squid /etc/squid/passwd
htpasswd /etc/squid/passwd [username]
</code>

Edit ''/etc/squid/squid.conf'':

<code conf /etc/squid/squid.conf>
auth_param basic program /usr/lib64/squid/basic_ncsa_auth /etc/squid/passwd
auth_param basic children 5
auth_param basic realm Squid Basic Authentication
auth_param basic credentialsttl 2 hours
acl auth_users proxy_auth REQUIRED
http_access allow auth_users
</code>

And reload squid:

  systemctl reload squid

===== Specify domain throught proxy =====

Squid 实现代理分流

<code>
acl proxyrule dstdomain [example1.org] [example2.org]
cache_peer [proxy:ip] parent [proxy:port] 0 round-robin proxy-only no-query name=px
cache_peer_access px allow proxyrule
never_direct allow proxyrule
</code>

''never_direct allow proxyrule'' 需要打个重点标记，加了后就 **能解决某些请求不经过 cache_peer 的问题** 。

===== Reference =====

  * [[https://hostpresto.com/community/tutorials/how-to-install-and-configure-squid-proxy-on-centos-7/|How to Install and Configure Squid Proxy on CentOS 7]]
  * [[https://wiki.squid-cache.org/SquidFaq/SquidAcl|Access Controls in Squid]]