In keeping with the Kali Linux Network Services Policy, no network services, including database services, run on boot as a default, so there are a couple of steps that need to be taken in order to get Metasploit up and running with database support.
Start the Kali PostgreSQL Service
Metasploit uses PostgreSQL as its database so it needs to be launched first.
You can verify that PostgreSQL is running by checking the output of ss -ant and making sure that port 5432 is listening.
LISTEN 0 128 :::22 :::*
LISTEN 0 128 *:22 *:*
LISTEN 0 128 127.0.0.1:5432 *:*
LISTEN 0 128 ::1:5432 :::*
Initialise the Metasploit PostgreSQL Database
With PostgreSQL up and running, we next need to create and initialize the msf database.
Launch msfconsole in Kali
Now that the PostgreSQL service is up and running and the database is initialized, you can launch msfconsole and verify database connectivity with the db_status command as shown below.
[*] postgresql connected to msf3