If you've started the vCloud Director service (vmware-vcd) but the Web UI is not showing up when you access it with your browser, here are some things to try.
First, make sure there is actually a problem. Does the $VCLOUD_HOME/logs/cell.log show that the application has initialized 100%? If not, you'll want to wait until that happens before trying to access the UI.
If the application is 100% initialized, try checking the following:
Does the netstat -nape command show two instances of java, one bound to the HTTP service IP and one bound to the console proxy IP?
If not, you should check the $VCLOUD_HOME/logs/vcloud-container-debug.log file to see if there are any relevant errors or exceptions that indicate why it was unable to bind to the appropriate IP addresses
You may also want to verify that $VCLOUD_HOME/etc/global.properties has the appropriate values for consoleproxy.host.https and vcloud.cell.ip.primary settings. If it does not you'll want to follow VMware KB 1028657 to fix the settings. Note: the two settings cannot use the same IP address, as both the HTTP service and the console proxy need to bind to port 443.
Can you telnet <primary ip> 443? If not, there may be a firewall blocking the connection or if the service is behind a load balancer or NAT is being utilized there is likely a misconfiguration in the LB or NAT settings.
If you're getting a fairly generic 404 error when you try to access https://<primary ip>/cloud or if you get a page listing the available contexts, the Web application that serves the Web UI has not fully deployed yet. You should wait a few minutes and then try again.