apache log 查看 Apache ProxyPass 出现503 Service Temporarily Unavailable

查看apache日志/var/log/httpd/error_log：
sudo vi /var/log/httpd/error_log

日志/var/log/httpd/access_log：
sudo vi /var/log/httpd/access_log

ap_proxy_connect_backend disabling worker for (127.0.0.1) for 60s
(13)Permission denied: AH00957: HTTP: attempt to connect to 127.0.0.1:8083 (127.0.0.1) failed
AH00959: ap_proxy_connect_backend disabling worker for (127.0.0.1) for 60s

解决办法
/usr/sbin/setsebool httpd_can_network_connect 1

root@ logs]# /usr/sbin/getsebool -a |grep http_can_network_connect
httpd_can_network_connect --> on

重新访问，页面果然可以访问了。