etcd software package provides highly-available key value store -- daemon, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install etcd
etcd is installed in your system.
Make ensure the etcd package were installed using the commands given below,
$ sudo dpkg-query -l | grep etcd *
You will get with etcd package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Development |
| Package | etcd |
| Version | 2.3.7+dfsg-5 |
| Description | highly-available key value store -- daemon |
| Sub Section | devel |