Can you check the merovingian.log file to see if it actually sees a client connecting, or maybe give another hint why things go wrong?
These lines appear in /usr/local/var/log/merovingian.log when I try to connect with mclient: MSG merovingian[8124]: database 'demo' already running since 2007-11-12 14:24: 35, up min/avg/max: 2/769/4851, crash average: 0.00 0.00 0.00 (10-9=0) MSG merovingian[8124]: redirecting client for database 'demo' to mapi:monetdb: //hp:50001/ The fact is that my host is reffered as "hp" (my machine name) and as "localhost". On my /etc/hosts file "hp" is an alias for 192.168.1.1 and not for 127.0.0.1, and beacuse of this mclient is blocked by my firewall. I changed my /etc/hosts file and now it works, but how to make MonetDB listen on "localhost" instead of "hp"? There is no option for that in /usr/local/etc/monetdb5.conf I find this error message as well when I start the "demo" db: ERR demo[8181]: #warning: please don't forget to set your vault key! ERR demo[8181]: #(see /usr/local/etc/monetdb5.conf) What is this about? Thanks for help Fabian!