As of Apache CloudStack 4.4, Java version required is 1.7 for the management-server, cloudstack-usage, KVM agent and system-VMs.
OVS plug-in functionality is disrupted if ovsdaemon crashes
A critical functionality issue came out with CLOUDSTACK-6779. On XenServer it is observed that on VIF unplug Ovs-Vswitchd is crashing resulting in loosing all the openflow rules added to the bridge. Ovs daemon gets started and creates a bridge but configure openflow rules are lost resulting in the disruption of connectivity for the VM’s on the host.
If using Active-Directory (LDAP/LDAPs) as user authentication; Upgrading to 4.3 and later require changes in Global Settings. After upgrading CloudStack to 4.3 or latest, following Global Settings must be change:
32bit versions of systemvm templates are in the process of behing deprecated. Upgrade instructions from this Release Notes use 64bit templates. 32bit systemvm-templates are available for this version on http://cloudstack.apt-get.eu/systemvm/4.4/. Follow the dev mailing list for further updates.
If you are experiencing CloudStack UI issues, please consider upgrading your tomcat instance to version 6.0.43 (tested version, but earlier versions prior to 6.0.37 might work as well), to address the tomcat response issues caused by latency between the browser/client and CloudStack Management server.