How to check if a particular service is running on Ubuntu

I don't have an Ubuntu box, but on Red Hat Linux you can see all running services by running the following command:

service --status-all

On the list the + indicates the service is running, - indicates service is not running, ? indicates the service state cannot be determined.

For Ubuntu (checked with 12.04)

You can get list of all services and select by color one of them with 'grep':

sudo service --status-all | grep postgres

Or you may use another way if you know correct name of service:

sudo service postgresql status

Maybe what you want is the ps command;

ps -ef

will show you all processes running. Then if you have an idea of what you're looking for use grep to filter;

ps -ef | grep postgres