Linkerd: Up and Running

Chapter 6. The Linkerd CLI

The Linkerd command line interface (CLI) is a useful tool for interacting with the Linkerd control plane. The CLI can help you check on the health of a Linkerd instance, view details about proxies and certificates, troubleshoot aberrant behavior, and view policy. It is the recommended way to directly interface with Linkerd. It handles all the major tasks you’ll need to work with your Linkerd installs and provides important tools for validating and examining Linkerd.

In this chapter, we’ll cover some of the most useful things the CLI can do and illustrate how to take best advantage of it. The CLI is, of course, constantly evolving as new Linkerd releases come out, so it’s always important to keep an eye on the official documentation.

Installing the CLI

The CLI is versioned along with the rest of Linkerd, so when you install the CLI, you’ll start by choosing which release channel to use.

To install from the stable channel, you’ll refer to the vendor instructions (such as those for Buoyant Enterprise for Linkerd).

To install completely open source Linkerd from the edge channel, you’ll refer to the Linkerd quickstart. At the time of this writing, that boils down to:

$ curl --proto '=https' --tlsv1.2 -sSfL https://run.linkerd.io/install-edge | sh

In either case, once you install the CLI you’ll need to add it to your PATH in the appropriate manner for your shell. For example, if you use bash you can alter the PATH variable directly:

$ export PATH=$HOME/.linkerd2/bin: ...