Working with proxies and jump hosts

Often, when it comes to configuring core network devices, these are isolated from the main network via a proxy or jump host. Ansible lends itself well to automating network device configuration as most of it is performed over SSH; however, this is only helpful in a scenario where Ansible can either be installed and operated from the jump host or, better yet, can operate via a host such as this.

Fortunately, Ansible can do exactly that. Let’s assume that you have two Cumulus Networks switches in your network (these are based on a special distribution of Linux for switching hardware, which is very similar to Debian). These two switches have the cmls01.example.com and cmls02.example.com hostnames, but both can only be accessed from a host called bastion.example.com.

The configuration to support our bastion host is performed in the inventory, rather than in the playbook. We begin by defining an inventory group with the switches in, in the...