Client Installation

IMPORTANT: Sensu Core reached end-of-life (EOL) on December 31, 2019, and we permanently removed the Sensu EOL repository on February 1, 2021.

This means the packages and https://eol-repositories.sensuapp.org URLs specified in the instructions and code examples on this page are no longer available. To migrate to Sensu Go, read the Sensu Core migration guide.

Install the Sensu Client

Having successfully installed and configured a Sensu server and API (Sensu Core or Sensu Enterprise), let’s now install and/or configure a Sensu client. The Sensu client is run on every system you need to monitor, including those running the Sensu server and API, and Sensu’s dependencies (i.e. RabbitMQ and/or Redis). Both Sensu Core and Sensu Enterprise use the same Sensu client process (i.e. sensu-client), so upgrading from Sensu Core to Sensu Enterprise does not require you to install a difference Sensu client.

Included in Sensu Core

The Sensu client process (sensu-client) is part of the open source Sensu project (i.e. Sensu Core) and it is included in the Sensu Core installer packages along with the Sensu Core server and API processes (i.e. sensu-server and sensu-api). This means that if you are following the instructions in this guide for a standalone installation, your Sensu client is already installed!

Disabled by default

The Sensu client process (sensu-client) is disabled by default on all platforms. Please refer to the corresponding configuration and operation documentation corresponding to the platform where you have installed your Sensu client(s) for instructions on starting & stopping the Sensu client process, and/or enabling the Sensu client process to start automatically on system boot.

Install Sensu Core

Ubuntu/Debian

Sensu Core is installed on Ubuntu and Debian systems via a native system installer package (i.e. a .deb file). The Sensu Core package installs several processes including sensu-server, sensu-api, and sensu-client.

Sensu packages for Debian target current stable and oldstable releases.

Sensu packages for Ubuntu target current Long Term Support (LTS) releases.

If you wish to install Sensu packages on newer Debian or Ubuntu releases, please try installing a package built for the most recent Debian stable or Ubuntu LTS release.

Install Sensu using APT (recommended)

NOTE: As of Sensu version 0.27, apt repository configuration has changed to include the “codename” of the Ubuntu/Debian release. To install or upgrade to the latest version of Sensu, please ensure you have updated existing repository configurations.

  1. Install the GPG public key: 

    wget -q https://eol-repositories.sensuapp.org/apt/pubkey.gpg -O- | sudo apt-key add -

  2. Determine the codename of the Ubuntu/Debian release on your system: 

    . /etc/os-release && echo $VERSION
"14.04.4 LTS, Trusty Tahr" # codename for this system is "trusty"

  3. Create an APT configuration file at /etc/apt/sources.list.d/sensu.list: 

    export CODENAME=your_release_codename_here # e.g. "trusty"
echo "deb     https://eol-repositories.sensuapp.org/apt $CODENAME main" | sudo tee /etc/apt/sources.list.d/sensu.list

  4. Update APT: 

    sudo apt-get update

  5. Install Sensu: 

    sudo apt-get install sensu
    NOTE: as mentioned above, the sensu package installs all of the Sensu Core processes, including sensu-client, sensu-server, and sensu-api.

  6. Configure Sensu. No “default” configuration is provided with Sensu, so none of the Sensu processes will run without the corresponding configuration. Please refer to the “Configure Sensu” section below, for more information on configuring Sensu. At minimum, all of the Sensu processes will need a working transport definition. The Sensu client will need a client definition, and both the sensu-server and sensu-api will need a data-store (Redis) definition — all of which are explained below.

RHEL/CentOS

Sensu Core is installed on RHEL and CentOS systems via a native system installer package (i.e. a .rpm file). The Sensu Core package installs several processes including sensu-server, sensu-api, and sensu-client.

Install Sensu using YUM (recommended)

Sensu packages for Red Hat target currently supported versions of Red Hat Enterprise Linux and their Centos equivalents. These packages are generally expected to be compatible with Red Hat derivatives like SuSE, Amazon or Scientific Linux, but packages are not tested on these platforms.

The following instructions describe configuring package repository definitions using Yum variables as components of the baseurl. On Red Hat derivative platforms the value of the $releasever variable will not typically align with the RHEL release versions (e.g. 6 or 7) advertised in the Sensu Yum repository. Please use 6 or 7 in lieu of $releasever on RHEL derivatives, depending on whether they use sysv init or systemd, respectively.

NOTE: As of Sensu version 0.27, the yum repository URL has changed to include the $releasever variable. To install or upgrade to the latest version of Sensu, please ensure you have updated existing repository configurations.

  1. Create the YUM repository configuration file for the Sensu Core repository at /etc/yum.repos.d/sensu.repo: 

    echo '[sensu]
name=sensu
baseurl=https://eol-repositories.sensuapp.org/yum/$releasever/$basearch/
gpgcheck=0
enabled=1' | sudo tee /etc/yum.repos.d/sensu.repo

  2. Install Sensu: 

    sudo yum install sensu
    NOTE: as mentioned above, the sensu package installs all of the Sensu Core processes, including sensu-client, sensu-server, and sensu-api.

  3. Configure Sensu. No “default” configuration is provided with Sensu, so none of the Sensu processes will run without the corresponding configuration. Please refer to the “Configure Sensu” section below, for more information on configuring Sensu. At minimum, all of the Sensu processes will need a working transport definition. The Sensu client will need a client definition, and both the sensu-server and sensu-api will need a data-store (Redis) definition — all of which are explained below.