1，设置“文件描述符”，并设置用户同时打开文件数量
# vi /usr/include/bits/typesizes.h
# vi /usr/include/linux/posix_types.h
把里边的 #define __FD_SETSIZE 1024 改成 65536
2，设置当前环境
# ulimit -Hs 65536
# ulimit -n 65536
H参数是硬性限制，s是堆栈上限，n是文件描述符上限
也可以永久修改这些限制，开机自动生效，配置如下：
vi /etc/security/limits.conf，添加以下内容
* soft nofile 65536
* hard nofile 65536
3，下载编译squid
可以到官方网站下载自己需要的版本，这里选用2.6版本
./configure --prefix=/usr/local/squid2.6 \
--enable-gnuregex \
--enable-icmp \
--enable-linux-netfilter \
--enable-default-err-language="Simplify_Chinese" \
--enable-follow-x-forwarded-for \
--enable-storeio=aufs,ufs \
--enable-kill-parent-hack \
--enable-cache-digests \
--with-maxfd=65536 \
--with-pthreads \
--enable-dlmalloc \
--enable-poll \
--enable-stacktraces \
--enable-removal-policies=heap,lru \
--enable-delay-pools
make
makeinstall
安装完毕后，可以到/usr/local/squid2.6目录去查看相关生成的文件，一般编译不出错，不会有啥问题。
4，配置squid.conf配置文件
配置文件如下：
acl all src 0.0.0.0/0.0.0.0
acl manager proto cache_object
acl localhost src 127.0.0.1/255.255.255.255
acl to_localhost dst 127.0.0.0/8
acl SSL_ports port 443
acl Safe_ports port 80 # http
acl Safe_ports port 21 # ftp
acl Safe_ports port 443 # https
acl Safe_ports port 70 # gopher
acl Safe_ports port 210 # wais
acl Safe_ports port 1025-65535 # unregistered ports
acl Safe_ports port 280 # http-mgmt
acl Safe_ports port 488 # gss-http
acl Safe_ports port 591 # filemaker
acl Safe_ports port 777 # multiling http
acl CONNECT method CONNECT
http_access allow manager localhost
http_access deny manager
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports
visible_hostname squid.abcd.cn
http_access allow localhost
http_access allow all
access_log /var/log/squid/access.log squid
cache_log /var/log/squid/cache.log
cache_store_log /var/log/squid/store.log
pid_filename /var/log/squid/squid.pid
cache_effective_user nobody
cache_effective_group nobody
http_port 80 vhost vport
cache_peer 10.10.10.1 parent 80 0 no-query no-digest originserver name=mail
cache_peer_domain mail mail.abcd.cn
cache_peer_access mail allow all
hierarchy_stoplist cgi-bin ?
cache_mem 256 MB
cache_swap_low 90
cache_swap_high 95
minimum_object_size 0 KB
maximum_object_size 32768 KB
maximum_object_size_in_memory 600 KB
ipcache_size 1024
ipcache_low 90
ipcache_high 95
cache_replacement_policy lru
memory_replacement_policy lru
cache_dir ufs /var/spool/squid 1600 16 256
acl QUERY urlpath_regex cgi-bin \? \.js
cache deny QUERY
refresh_pattern ^ftp: 1440 20% 10080
refresh_pattern ^gopher: 1440 0% 1440
refresh_pattern . 0 20% 4320
acl apache rep_header Server ^Apache
broken_vary_encoding allow apache
coredump_dir /var/spool/squid
##########################################################
header_access Via deny all
header_access Server deny all
header_access X-Cache deny all
header_access X-Cache-Lookup deny all
httpd_suppress_version_string off
# mkdir /var/log/squid //建立日志目录
# chown nobody:nobody /var/log/squid //用户nobody用户和组来运行squid
# mkdir /var/spool/squid //建立squid缓存目录
# chown nobody:nobody /var/spool/squid //同样，给权限
# /usr/local/squid2.6/sbin/squid -z //建立缓存目录
# ls /var/spool/squid //查看是否建立成功
5，开机自动运行squid
vi /etc/rc.d/rc.local
将以下内容添加最下边
ulimit -Hs 65536
ulimit -n 65536
/usr/local/squid2.6/sbin/squid
如果你添加ulimit到/etc/security/limits.conf配置文件了，就不需要在这里写了。
更改配置文件后，重新加载：
/usr/local/squid2.6/sbin/squid -k reconfigure
停止squid程序：
/usr/local/squid2.6/sbin/squid -k shutdown
查看缓存信息：
squidclient -p 80 mgr:info
squidclient -p 80 mgr:mem