# Advice on Tower with GCE and machine credential authentication **URL:** \ **Category:** Ansible Project\ **Created:** [April 25, 2015, 9:01pm UTC](https://forum.ansible.com/t/advice-on-tower-with-gce-and-machine-credential-authentication/18087 "2015-04-25T21:01:36Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![Adrian\_Black](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@Adrian\_Black](https://forum.ansible.com/u/Adrian_Black)\ **Post date:** [April 25, 2015, 9:01pm UTC](https://forum.ansible.com/t/advice-on-tower-with-gce-and-machine-credential-authentication/18087/1 "2015-04-25T21:01:36Z")
Hi I am evaluating tower on google compute engine. The dynamic inventory has been ok and that is working I managed to get it working with ansible-playbook but i cant figure out a good way to do the Machine Credentials authentication from tower for jobs. For simple ssh username and password what do i specify? Should i create a bespoke user on each machine, but then how do i do this for autoscaling - startup script, baked into snapshot disk? Just to get it working i wouldnt mind using the core user that is created when you login via the ssh option in the console but a) i dont know the password for that user or b) the private key so dont know what to put. Im new to Linux which doesnt help esp trying to understand all this authentication stuff. Anyone done this and have a best practice? Thanks ---
**Author:** ![Brian\_Coca](https://avatars.discourse-cdn.com/v4/letter/b/6de8d8/32.png) [@Brian\_Coca](https://forum.ansible.com/u/Brian_Coca)\ **Post date:** [April 27, 2015, 4:13pm UTC](https://forum.ansible.com/t/advice-on-tower-with-gce-and-machine-credential-authentication/18087/2 "2015-04-27T16:13:52Z")
For tower questions please submit to support@ansible.com, these lists and the IRC channels are for the ansible OSS command line utility.