Sitecore Content Delivery Role:
On this page you will find all related to howto configure the servers:
https://doc.sitecore.net/sitecore_experience_platform/82/setting_up_and_maintaining/xdb

This page has a summary about the scalability options. It is useful to understand why we split Sitecore into CM and CD:
https://doc.sitecore.net/sitecore_experience_platform/82/setting_up_and_maintaining/xdb/platform/scalability_options

Here is the full explanation about how to configure a CA server:
https://doc.sitecore.net/sitecore_experience_platform/82/setting_up_and_maintaining/xdb/configuring_servers/configure_a_content_management_server

Here is the full explanation of how to configure a CD server. It’s quite complex:
https://doc.sitecore.net/sitecore_experience_platform/82/setting_up_and_maintaining/xdb/configuring_servers/configure_a_content_delivery_server

So, if you don’t want to spend several days applying all configuration manually, this is the solution:
https://github.com/sitecore/sitecore-configuration-roles

In fact, this easy way works so well, that Sitecore took it and implement it on SC9 as an out-of-the-box feature. You can see it in the official SC9 documentation:
https://doc.sitecore.net/developers/server-role-configuration-reference/core-roles/content-delivery.html

Sitecore + Solr in cluster:
This is the official documentation that Sitecore provides:
https://doc.sitecore.net/sitecore_experience_platform/setting_up_and_maintaining/search_and_indexing/walkthrough_setting_up_solr

This blog explains it in a detailed way (disclaimer: I don’t have Solr skills to check this blog):

Sitecore on Solr Cloud: Part 1 – Architecture

Sitecore on Solr Cloud: Part 2 – Setting up Zookeeper and Solr

Sitecore on Solr Cloud: Part 3 – Creating Your Sitecore Collection

Sitecore on Solr Cloud: Part 4 – Tuning Solr for Production

Here is another blogs:
https://sitecore-community.github.io/docs/search/solr/Install-and-configure-SolrCloud/

Setup Solr for Sitecore Production

Unicorn:
Official source and documentation about it. The process to implement it in CI is on this page:
https://github.com/kamsar/Unicorn

About how to use Transparent Sync:
https://kamsar.net/index.php/2015/10/Unicorn-Introducing-Transparent-Sync/

As a Plan-B, don’t forget you have Sitecore Ship to push item packages to different environments:
https://github.com/kevinobee/Sitecore.Ship