Even in a small environment, roles are quite useful. I use them for clusters as small as 4.
Roles do not have to be 1:1 to host groups (but can be). You might have roles apache, and postgres. Each of those would install the base packages on top of your basic config, which might be handled by your common role. Then, you might have a more specific role for each service or customer. Those would layer the specific configs on top of the packages. If you use role dependencies, you're guaranteed that the packages would be there. This allows you to have top level roles that use other (standardized) roles as building blocks. Then you can get into situations where different groups, or even organizations, maintain the different roles. Your security office might maintain a role that ensures that your machines meet our organization's security requirements. ^^ On Thu, Aug 25, 2016 at 10:57 AM Alan Evangelista <alan.vi...@gmail.com> wrote: > I'm a little confused in understanding the exact purpose of roles. Reading > http://docs.ansible.com/ansible/playbooks_roles.html , the first examples > use a 1:1 association between role and hosts group (eg webservers and > dbservers). This makes the "role" terminology meaningful to me, as it is > representing a set of machines which have a role in the infrastructure. > However, later in the same web page I see examples with roles named > "apache" and "postgres", which are only applications in one or more > machines. I'd assume that the setup of these applications would be only > tasks, not roles. > > Questions: > > - In the first case, could not I simply associate a group of hosts with > variables? Why use roles? > - In the second case, could I not simply associate a group of hosts with > "apache" and "postgres" setup tasks? Why use roles? > > At first sight, roles seem overkill to me, specially in a small > infrastructure with a few machines such as the one I have. > > -- > You received this message because you are subscribed to the Google Groups > "Ansible Project" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to ansible-project+unsubscr...@googlegroups.com. > To post to this group, send email to ansible-project@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/ansible-project/bcbdba7d-8c7d-4c14-b42b-d177a7faf763%40googlegroups.com > <https://groups.google.com/d/msgid/ansible-project/bcbdba7d-8c7d-4c14-b42b-d177a7faf763%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- -- Nobody believed that I could build a space station here. So I built it anyway. It sank into the vortex. So I built another one. It sank into the vortex. The third station burned down, fell over then sank into the vortex. The fourth station just vanished. And the fifth station, THAT stayed! -- You received this message because you are subscribed to the Google Groups "Ansible Project" group. To unsubscribe from this group and stop receiving emails from it, send an email to ansible-project+unsubscr...@googlegroups.com. To post to this group, send email to ansible-project@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/ansible-project/CAA2%3DfcqVJwu%2BQB82i5ifo%2BLWYFQ3BOpL2tf%3DxqrK1ODNhn%2BVTw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
