Zimbra webmail not working on port 80/443

On Zimbra mail server, webmail stopped working on Port 80/443. Admin interface worked properly on url https://hostname:7071/. There is no errors displayed under monitor tab of Zimbra Admin.

To fix, run

su - zimbra
zmprov ms `zmhostname` zimbraReverseProxySSLToUpstreamEnabled FALSE
zmprov ms `zmhostname` zimbraMailMode both
zmprov ms `zmhostname` zimbraReverseProxyMailMode both
./libexec/zmproxyconfig -e -w -o -a 8080:80:8443:443 -x both -H `zmhostname`
zmcontrol restart

After running this, netstat -lntp start showing nginx running on port 80 and 443

root@zim:~# netstat -lntp | egrep "80|443"
tcp        0      0 127.0.0.1:10663         0.0.0.0:*               LISTEN      10980/zmlogger: zmr
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      11354/nginx.conf
tcp        0      0 127.0.0.1:8080          0.0.0.0:*               LISTEN      11098/java      
tcp        0      0 116.203.102.86:8080     0.0.0.0:*               LISTEN      11098/java      
tcp        0      0 0.0.0.0:443             0.0.0.0:*               LISTEN      11354/nginx.conf
tcp6       0      0 :::7780                 :::*                    LISTEN      11707/httpd     
root@zim:~#