Sync user roles across websites I am using Drupal 7. I want to sync my Drupal website roles on 2 websites on the same top level domain, as in, one is example.com, the other is other.example.com, how can i achieve this? Bakery module does not seem to share user roles, and i want to avoid sharing databases across my sites since it works but not recommended.

Basically, i want to reduce loading time on my main site and push my payment system (which contains many modules) to a new Drupal install so that when the payment is made on the slave site, the user role is updated on the slave site which is in turn captured on the main site. How can i achieve this?
i cannot provide detailed steps to achieve this but there are various alternatives Comparison of Single Sign On (SSO) Modules to the bakery module you mentioned that are capable of sharing users. although you might want to just create those roles via a feature, depending on what you mean by 


  sync my drupal website roles.



Services
i18n_sso
Domainaccess
CAS
account_sync
simplesamlphp_auth
shib_auth
Omniauth https://drupal.org/node/2177681
Oauth Connector
Bakery 3.x current development effort suggest it might soon support exporting roles in 3.x if you are a developer you can look there. i believe issue 556666 was committed to 2.x already aswell