配置.htaccess如下：
RewriteEngine on RewriteBase / RewriteCond $1 !^(index\.php|images|robots\.txt|css|js); RewriteRule ^(.*)$ /sis/index.php/$1 [L]
Apache（error.log）报错如下：
12220:tid 1848] [client ::1:50815] AH00124: Request exceeded the limit of 10 internal redirects due to probable configuration error. Use ‘LimitInternalRecursion‘ to increase the limit if necessary. Use ‘LogLevel debug‘ to get a backtrace. [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3590): [client ::1:50815] AH00121: r->uri = /sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/news/create [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3596): [client ::1:50815] AH00122: redirected from r->uri = /sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/news/create [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3596): [client ::1:50815] AH00122: redirected from r->uri = /sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/news/create [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3596): [client ::1:50815] AH00122: redirected from r->uri = /sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/news/create [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3596): [client ::1:50815] AH00122: redirected from r->uri = /sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/news/create [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3596): [client ::1:50815] AH00122: redirected from r->uri = /sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/news/create [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3596): [client ::1:50815] AH00122: redirected from r->uri = /sis/index.php/sis/index.php/sis/index.php/sis/index.php/sis/index.php/news/create [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3596): [client ::1:50815] AH00122: redirected from r->uri = /sis/index.php/sis/index.php/sis/index.php/sis/index.php/news/create [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3596): [client ::1:50815] AH00122: redirected from r->uri = /sis/index.php/sis/index.php/sis/index.php/news/create [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3596): [client ::1:50815] AH00122: redirected from r->uri = /sis/index.php/sis/index.php/news/create [Thu Sep 10 14:24:14.491172 2015] [core:debug] [pid 12220:tid 1848] core.c(3596): [client ::1:50815] AH00122: redirected from r->uri = /sis/index.php/news/create
搜集到的有用的参考资料：http://www.askapache.com/htaccess/modrewrite-tips-tricks.html
Loop Stopping Code ^ Sometimes your rewrites cause infinite loops, stop it with one of these rewrite code snippets. RewriteCond %{REQUEST_URI} ^/(stats/|missing\.html|failed_auth\.html|error/).* [NC] RewriteRule .* - [L] RewriteCond %{ENV:REDIRECT_STATUS} 200 RewriteRule .* - [L]
修改后的.htaccess
RewriteEngine on RewriteBase / RewriteCond %{ENV:REDIRECT_STATUS} 200 RewriteRule .* - [L] RewriteCond $1 !^(index\.php|images|robots\.txt|css|js); RewriteRule ^(.*)$ /sis/index.php/$1 [L]
问题解决：浏览器地址栏中输入http://localhost/sis/news（不用输入index.php），页面打开正常。
解决Use 'LimitInternalRecursion' to increase the limit if necessary的问题 CodeIgniter .htaccess
原文：http://www.cnblogs.com/sinodragon21/p/4797863.html