I look for two things when considering configuration tools.
1. How does it handle cross-cutting concerns?
2. How does it handle complex configuration files?
For the cross-cutting concerns I use the firewall as an example. I look to see how multiple projects and modules (that are going to be installed on a machine) can declare their firewall rules.
On the complex configuration files, I usually consider Nginx and how to define multiple SSL certificates, SSL ciphers, load balancer backends, multiple web sites, and rules for locations on those websites.
On Nginx... perhaps I'm lost in the docs but beyond simple installation I don't see either attempting to handle the config files. Is it the case that one should deploy their own config or write something to define the config from templates? I must be wrong on that, but lack of clear and deep documentation on how to configure Nginx would mean I touch neither and stay with Puppet.
Any (configuration)file can be installed and/or templated with both Ansible and Salt. This includes whatever Nginx has for configuration.
I'm not 100% with both, but I guess you have nginx be installed in some dedicated pillar/playbook and you can have your application pillar/playbook include templated configuration files to be inserted into /etc/nginx/conf.d and notify the service to be reloaded somehow.
But when it's clearly a scenario that everyone using Nginx will be writing these templates, surely it's better to have a well maintained master copy of them.
The complexity usually comes in having multiple projects wanting to modify the template(s) to wire themselves up.
A good sign for config tools is a feature rich and well maintained recipe/playbook (whatever you want to call it) that is able to do the non-trivial things (most deploy scripts for nginx don't seem to deal with SSL particularly elegantly with all of the options involved).
What I look for in a config tool is such good defaults for handling these complex (but commonplace) scenarios, that the recipes/modules/playbooks are mature, dependency-free and well-maintained.
I guess I'm spoiled by programming in Go, I've got used to the idea that the language includes a stdlib comprehensive enough that 90% of what you need (even with those complex things like "give me a web server") is all built in.
That's the problem I'm trying to solve whenever I consider abandoning Puppet... dependency hell.
But I also remember the pains when I first used Puppet: cross-cutting concerns and complex configurations.
1. How does it handle cross-cutting concerns?
2. How does it handle complex configuration files?
For the cross-cutting concerns I use the firewall as an example. I look to see how multiple projects and modules (that are going to be installed on a machine) can declare their firewall rules.
I'm a Puppet user presently, but a quick look says that Ansible has great firewall support ( http://docs.ansible.com/ufw_module.html ) in a nice tight format, and SaltStack has iptables support in a more verbose format: http://docs.saltstack.com/en/latest/ref/states/all/salt.stat...
On the complex configuration files, I usually consider Nginx and how to define multiple SSL certificates, SSL ciphers, load balancer backends, multiple web sites, and rules for locations on those websites.
On Nginx... perhaps I'm lost in the docs but beyond simple installation I don't see either attempting to handle the config files. Is it the case that one should deploy their own config or write something to define the config from templates? I must be wrong on that, but lack of clear and deep documentation on how to configure Nginx would mean I touch neither and stay with Puppet.