After months of development the moment comes where one must endure the human firewalls (system administrators).
We will have 10000 contacts and in deveopment environment i always used a MSSQL database.
Now i was told every application must’nt directly access Databases inside the infrastructure, that should be done through Web services.
As i have no time to change openfire database transactions to webservices i am willing to use the embedded database.
I expect a lot of contacts but phew users using the server simultaneously (max 200). where will the limitations of the embedded database will be more problematic? roster retrieval? authentication? database size? throughtput? backup and admin?
the database tables are held in momory. So if you enable the monitoring plugin and users chat a lot then you will see a much bigger memory usage. One can workaround this by changing the table definitions, but then you no longer have a standard Openfire installation.
I don’t think that 10000 contacs cause problems, see also http://hsqldb.org/ as this is the used database. It should be very easy to import a MySQL dump into HSQLDB and then start a test server for a quick test.
If I were you I would declare Openfire as be a Web Service. It looks like your company does a lot to make things more complicated and slowly. So I expect that Openfire must also use an ESB to deliver emails instead of using sendmail. And in a few weeks, after a lot of thinking of your management you must also route all xmpp packets over an ESB.