.NET: deployment SQL connection string -

i've got .net project have deploy on different machines different enviroments.

some machines use internal network addresses access db others have on public internet ips.

what best practices configure sql connection strings in web.config such task?

you may have setting form in project witch can accessed user before activity db. in project's login section (if project has any!). in form can ask user input appropriate db setting (ip,userid , password) , reset conectionstring in app.config , restart app. action has take place first time application runs on specific machine.