Open Source Document Management System | OpenKM

Hi, congratulations to the OpenKM community for the contribution that is being done with this tool, I'm implementing openkm over ubuntu, I had no problems installing, everything is perfect, now I'm on the settings stage but I am having a little problem, every time I restart the server, the users who had created disappear. anyone have any idea what happens? I need to fix something '? or is it a bug OpenKM?

before login I get the following message "WARNING hibernate.hbm2ddl = create" something to do? What if that means?
thank you in advance for your response. Greetings

[Solved] to fix it just replace "hibernate.hbm2ddl = create" by "hibernate.hbm2ddl = none" from config file OpenKM.cfg.thanks anyway