nginx配置auth basic提示500错误

nginx配置文件如下

location /monit/ {        auth_basic "Root";        auth_basic_user_file /var/www/ops/conf/passwd.db;        proxy_set_header         Connection       "";        proxy_set_header         X-Real_IP        $remote_addr;        proxy_pass http://192.168.0.6:19999/;     }

nginx -V

root@24f009dd335c:/# nginx -Vnginx version: nginx/1.10.1built with OpenSSL 1.0.2i  22 Sep 2016 (running with OpenSSL 1.0.2j  26 Sep 2016)TLS SNI support enabledconfigure arguments: --with-cc-opt='-g -O2 -fdebug-prefix-map=/build/nginx-7jgWGO/nginx-1.10.1=. -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2' --with-ld-opt='-Wl,-z,relro -Wl,-z,now' --prefix=/usr/share/nginx --conf-path=/etc/nginx/nginx.conf --http-log-path=/var/log/nginx/access.log --error-log-path=/var/log/nginx/error.log --lock-path=/var/lock/nginx.lock --pid-path=/run/nginx.pid --modules-path=/usr/lib/nginx/modules --http-client-body-temp-path=/var/lib/nginx/body --http-fastcgi-temp-path=/var/lib/nginx/fastcgi --http-proxy-temp-path=/var/lib/nginx/proxy --http-scgi-temp-path=/var/lib/nginx/scgi --http-uwsgi-temp-path=/var/lib/nginx/uwsgi --with-debug --with-pcre-jit --with-ipv6 --with-http_ssl_module --with-http_stub_status_module --with-http_realip_module --with-http_auth_request_module --with-http_v2_module --with-http_dav_module --with-http_slice_module --with-threads --with-http_addition_module --with-http_flv_module --with-http_geoip_module=dynamic --with-http_gunzip_module --with-http_gzip_static_module --with-http_image_filter_module=dynamic --with-http_mp4_module --with-http_perl_module=dynamic --with-http_random_index_module --with-http_secure_link_module --with-http_sub_module --with-http_xslt_module=dynamic --with-mail=dynamic --with-mail_ssl_module --with-stream=dynamic --with-stream_ssl_module --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/headers-more-nginx-module --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/nginx-auth-pam --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/nginx-cache-purge --add-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/nginx-dav-ext-module --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/nginx-development-kit --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/nginx-echo --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/ngx-fancyindex --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/nchan --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/nginx-lua --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/nginx-upload-progress --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/nginx-upstream-fair --add-dynamic-module=/build/nginx-7jgWGO/nginx-1.10.1/debian/modules/ngx_http_substitutions_filter_module

浏览器打开500 Internal Server Error
curl 提示401

error.log

2016/10/27 20:22:31 [crit] 3291#3291: *2611 open() "/var/www/ops/conf/passwd.db" failed (13: Permission denied), client: ip, server: a.com, request: "GET /monit/api/v1/alarms?active&_=1477553620900 HTTP/2.0", host: "a.net", referrer: "https://a.net/monit/"

passwd.db权限

-rwxrwxrwx 1 www-data www-data   20 Oct 26 19:53 passwd.db