After installing Zimbra Collaboration 8.8 or upgrading from previous version you may get blank screen in some cases when accessing your management URL or Web interface.
In our example we are using mysite.com smtp domain with server named mail.mysite.com
In the nginx log file you will see following entries
cat /opt/zimbra/log/nginx.log ............client closed connection while waiting for request, client:..............
Fixing this issue
There was some changes made by Zimbra to the way nginx behaves with new version 8.8. This is how we fixed this problems.
su zimbra zmprov md mysite.com zimbraVirtualHostname mail.mysite.com zimbraVirtualIPAddress "zimbra server ip address" cd libexec/zmproxyconfgen zmproxyctl restart
After this steps you should be able to access your management interface at https://mail.mysite.com:7071 and web interface at https://mail.mysite.com