我想在一个VirtualHost authnz_external模块中为系统用户使用，而mpm-itk模块在另一个用户下运行它。 我的VirtualHost的configuration文件看起来类似这样：
<VirtualHost *:8081> AddExternalAuth pwauth /usr/bin/pwauth SetExternalAuthMethod pwauth pipe <IfModule mpm_itk_module> AssignUserId user1 apache </IfModule> <Directory /var/www/user1_folder/> AuthType Basic AuthUserFile /var/www/user1_folder/apache.users AuthName "private area" AuthBasicProvider external AuthExternal pwauth require valid-user </Directory> </VirtualHost> 但是，如果我使用这种configuration，我不能login到networking。 在Apache的error_log文件中是这样的：
[Wed Jun 14 15:43:04.449652 2017] [unixd:alert] [pid 17150] (1)Operation not permitted: AH02156: setgid: unable to set group id to Group 0 [Wed Jun 14 15:43:12.027069 2017] [authnz_external:error] [pid 17149] [client 83.158.44.101:59772] AuthExtern pwauth [/usr/bin/pwauth]: Failed (1) for user user1 [Wed Jun 14 15:43:12.027108 2017] [auth_basic:error] [pid 17149] [client 83.158.44.101:59772] AH01617: user user1: authentication failure for "/user1_folder": Password Mismatch
如果我禁用mpm-itk模块或authnz_external模块都可以正常工作。
CentOS 7.3，httpd 2.4.6，mod_authnz_external 3.3.1，pwauth 2.3.10，httpd-itk 2.4.7.04