Since sqlite3 support was cut out in recent versions of Metasploit most of the tutorials won’t work anymore 
In my copy of BackTrack5 PostgreSQL was NOT installed. To get it type
apt-get install postgresql
When it’s done you have to change the password of the postgres database admin. I used “toor” as password…simple isn’t it
sudo -u postgres psql \password postgres \q
After that we crate our database:
sudo -u postgres createdb -0 postgres autopwn
Then restart. Back in Metasploit fill your new created database with:
db_connect postgres:toor@127.0.0.1/autopwn
Well you might first need to start the proper driver and perhaps do some gem installs.
db_driver postgresql
Now Nmap your LAN and happy autopwning
Note: If you still get errors make sure you started Metasploit from the menu entry of the X console since this will make sure that all necessary variables are set.
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