If you are planning to deploy HCL Sametime Community service in a cluster or HA architecture, setting a Community ID is a must. Ideally, this should be an FQDN used for accessing the Community servers, something which is easy to remember, and your users can relate to. So, think ahead and use a name that can be used to access the service externally and internally

In one customer situation I had the request to disable the new ( and great ) functionality of the persistant chat.Well, you have to install the MongoDB during the installation of the Sametime Community Server but can disable the need of the MongoDB afterwards by going through the following steps