Zimbra Collaboration 8.8 blank screen after install

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

Troubleshooting

In the nginx log file you will see following entries

cat /opt/zimbra/log/nginx.log
............client closed connection while waiting for request, client:..............


There is 2 ways this issue can be fixed

Fix #1

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

Fix #2

zmprov ms `zmhostname` +zimbraServiceEnabled service
zmprov ms `zmhostname` +zimbraServiceEnabled zimbra
zmprov ms `zmhostname` +zimbraServiceEnabled zimbraAdmin
zmprov ms `zmhostname` +zimbraServiceEnabled zimlet
zmcontrol 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