Chapter 13. Zero-Touch Provisioning
When a fixed-configuration Arista switch boots and no startup-config is found, the switch defaults to Zero-Touch Provisioning (ZTP) mode. Your first reaction to ZTP might be that it’s a pain in the ass, but I assure you it’s not, and I hope that by the end of this chapter, you’ll agree. In fact, it’s a seriously cool feature that you can use to great effect.
Technically what triggers ZTP (when it’s enabled) is a missing startup-config or one that is zero bytes in size.
Have you ever installed a new switch out of the box? Chances are that you mounted it and sat in the data center with a console cable, or you sat with it on your desk while your workmates plotted against you because of all the fan noise. Or consider the idea of remote installations. I’ve had many clients who have bought remote “smart” hands service, only to discover that those remote hands weren’t so smart after all. ZTP is designed to provide the ability to eliminate both situations, all through the use of standards-based Dynamic Host Configuration Protocol (DHCP).
The reason I say that it can be a pain is because when a new switch is powered up and steps to use ZTP have not been taken, configuring the switch is next to impossible. Here’s the first indication that you’re in for a long day if you have no idea how Arista switches behave. When you press Enter at the login prompt of a new switch, you’re greeted with the following warning:
localhost login: No startup-config was ...