读取错误
错误描述：(60)Operation timed out
现象：某些网站无法打开（比如google.com.hk），或开始能够打开部分内容但页面刷新几次后反而无法打开，提示“读取错误”
解决方法：squid.conf配置文件中的 acl allowmax maxconn 30，将最大连接数设置大一点，网页无法打开的原因，可能是因为网页包含的资源文件太多，超过了最大的连接数。
访问被拒绝
当尝试取回该 URL 时遇到下面的错误：http://www.163.com/
访问被拒绝。
Access control configuration prevents your request from being allowed at this time. Please contact your service provider if you feel this is incorrect.
缓存服务器的管理员 admin@domain.com.
解决方法
1、代理服务器机器的DNS配置问题，代理服务器机器不能找到指定url的ip地址导致。检查/etc/resolv.conf文件配置是否正确，如不正确添加正确的配置信息，比如说：
nameserver ###.###.###.###
nameserver ###.###.###.###
可以配置多个DNS server。
重新启动squid服务。
2、访问控制http_access allow all
无法进行转送操作
当尝试取回该 URL 时遇到下面的错误：http://ip/
目前无法将您的请求进行转送操作
This request could not be forwarded to the origin server or to any parent caches. The most likely cause for this error is that the cache administrator does not allow this cache to make direct connections to origin servers, and all configured parent caches are currently unreachable.
参考：http://home.arcor.de/pangj/squid/chap10.html
检测squid.conf配置 squid -k parse 报错
WARNING: Netmasks are deprecated. Please use CIDR masks instead.
2010/10/31 21:39:41| WARNING: IPv4 netmasks are particularly nasty when used to compare IPv6 to IPv4 ranges.
2010/10/31 21:39:41| WARNING: For now we will assume you meant to write /28
2010/10/31 21:39:41| WARNING: Netmasks are deprecated. Please use CIDR masks instead.
2010/10/31 21:39:41| WARNING: IPv4 netmasks are particularly nasty when used to compare IPv6 to IPv4 ranges.
2010/10/31 21:39:41| WARNING: For now we will assume you meant to write /28
解决方法
将配置文件中的192.168.1.0/255.255.255.0 改为 192.168.1.0/24 形式就OK了。
squid缓存目录没有权限
2004/11/01 23:06:29| Creating Swap Directories
FATAL: Failed to make swap directory /Cache1/00: (13) Permission denied
Squid Cache (Version 2.5.STABLE7): Terminated abnormally.
CPU Usage: 0.000 seconds = 0.000 user + 0.000 sys
Maximum Resident Size: 0 KB
Page faults with physical i/o: 10
解决方法：
/Cache1目录权限错误，请检查/Cache1目录所有者是否为squid用户所有