starting Hashicorp vault in server mode under docker container

Running Hashicorp vault in development mode is really easy, but starting the vault in server mode under a docker container may have some changes described in this article.

There are several simple steps, which is hard to get in one place, to run a Hashicorp vault in server mode (under docker):

  1. Prepare the directories to map in the docker. The data in the directories will be safe and won’t be deleted if the container is deleted.
  2. Prepare an initial base configuration to start the server. Without it, the server won’t startup. Even it is really simple.
  3. Start the Hashicorp vault process in a docker container.
  4. Initiliza the vault. During this step, the server will generate the database backend storage (files or in-memory or cloud backends) and 5 unseal keys and an administrative root token will be generated. To manage the vault an administrative user is required.
  5. Unseal the vault. Unencrypt the database backend to use the service with at least three commands and three different unseal keys generated during the initialization step.
  6. Login with the administrative user and enable vault engine to store values (or generate tokens, passwords, and so on). The example here enables the secret engine to store key:value backend. Check out the secrets engines – https://www.vaultproject.io/docs/secrets

STEP 1) Summary of the mapped directories in the docker

Three directories are preserved:

  • /vault/config – contains configuration files in HCL or JSON format.
  • /vault/data – the place, where the encrypted database files will be kept only if a similar storage engine is used like “file” or “raft” storages. More information here – https://www.vaultproject.io/docs/configuration/storage
  • /vault/log – writing persistent audit logs. This feature should be enabled explicitly in the configuration.

The base directory used is /srv/vault/. And the three direcotries are created as follow and will be mapped in the docker container:

mkdir -p /srv/vault/config /srv/vault/data /srv/vault/log

The server’s directory /srv/vault/config will be mapped in docker’s directory /vault/config and the other two, too.

STEP 2) Initial base configuration

The initial configuration file is placed in /vault/config/config.hcl and is using HCL format – https://github.com/hashicorp/hcl. The initial configuration is minimal:

storage "raft" {
  path    = "/vault/data"
  node_id = "node1"
}

listener "tcp" {
  address     = "127.0.0.1:8200"
  tls_disable = 1
}

disable_mlock = true

api_addr = "http://127.0.0.1:8200"
cluster_addr = "https://127.0.0.1:8201"
ui = true

Place the file in /srv/vault/config/config.hcl

STEP 3) Start the Hashicorp vault server in docker

Mapping the three directories.

root@srv ~ # docker run --cap-add=IPC_LOCK -v /srv/vault/config:/vault/config -v /srv/vault/data:/vault/data -v /srv/vault/logs:/vault/logs --name=srv-vault vault server
==> Vault server configuration:

             Api Address: http://127.0.0.1:8200
                     Cgo: disabled
         Cluster Address: https://127.0.0.1:8201
              Go Version: go1.14.7
              Listener 1: tcp (addr: "127.0.0.1:8200", cluster address: "127.0.0.1:8201", max_request_duration: "1m30s", max_request_size: "33554432", tls: "disabled")
               Log Level: info
                   Mlock: supported: true, enabled: false
           Recovery Mode: false
                 Storage: raft (HA available)
                 Version: Vault v1.5.3
             Version Sha: 9fcd81405feb320390b9d71e15a691c3bc1daeef

==> Vault server started! Log data will stream in below:

Keep on reading!

ansible – using ansible vault with copy module to decrypt on-the-fly files

Here is an interesting tip for all who what to protect the sensitive information with ansible. Our example is simple enough – we want to protect our private key and we want to decrypt it when installing on the server. The copy ansible module has a decrypt feature and it can decrypt the file on-the-fly when the task is executed.
Here is how to use ansible vault to encrypt the file with the private key and the ansible playbook file to copy the file.

If you are a newbie in ansible you can check this article – First ansible use – install and execute a single command or multiple tasks in a playbook There you can see how to create your inventory file (and configure sudo if you remotely log in with unprivileged user) used herein the example.

STEP 1) Encrypt the file with ansible vault

myuser@srv ~ $ ansible-vault encrypt server.key
New Vault password: 
Confirm New Vault password: 
Encryption successful

You can see the file now is changed and starts with:

myuser@srv ~ $ cat server.key 
$ANSIBLE_VAULT;1.1;AES256
62363263663865646361643461663531373637386631646262366333663831643435633263363336
3735326665326363356566303566626638316662376432640a326362326230353966353431383164
35353531653331306430656562616165353632643330393662313535326438363964303436306639
....
....

STEP 2) Ansible playbook file to use copy and decrypt option

---
- hosts: all
  tasks:
    - name: Copy server private key
      copy:
        src: server.key
        dest: /etc/env/server.key
        decrypt: yes
        owner: root 
        group: root 
        mode: 400
        backup: no

STEP 3) Execute the ansible playbook

myuser@srv ~ $ ansible-playbook --ask-vault-pass -l srv3 -i ./inventory.ini ./playbook-example.yml -b
Vault password: 

PLAY [all] *****************************************************************************************************************************************************************

TASK [Gathering Facts] *****************************************************************************************************************************************************
ok: [srv3]

TASK [Copy server private key] *********************************************************************************************************************************************
changed: [srv3]

PLAY RECAP *****************************************************************************************************************************************************************
srv3                       : ok=2    changed=1    unreachable=0    failed=0   

And the file in the remote server (srv3 in the example) is unencrypted in /etc/env/server.key!

First ansible use – install and execute a single command or multiple tasks in a playbook

This article is to show you how easy is to use automation tools for managing your servers. If you are new to ansible this article is right for you!

Installation

First, you must install ansible, which is pretty easy. At present all Linux distributions have the ansible package:

Ubuntu

sudo apt install ansible

CentOS 7

sudo yum install ansible

Fedora

sudo dnf install ansible

Gentoo

emerge -v ansible

Multiple python (version 3) packages will be pulled because the tool is based on python. The following files will appear in your machine (and a lot of python modules under the python directory of your Linux distribution):

/usr/bin/ansible
/usr/bin/ansible-config -> ansible
/usr/bin/ansible-connection
/usr/bin/ansible-console -> ansible
/usr/bin/ansible-doc -> ansible
/usr/bin/ansible-galaxy -> ansible
/usr/bin/ansible-inventory -> ansible
/usr/bin/ansible-playbook -> ansible
/usr/bin/ansible-pull -> ansible
/usr/bin/ansible-vault -> ansible

The important program name is ansible, with which you can do any of the other task.

What you can do using ansible with simple words

At present (July 2019) ansible 2.8.x has around 2080 modules (all modules here https://docs.ansible.com/ansible/latest/modules/list_of_all_modules.html) so you will find a solution for any automation task you may encounter. But here our purpose is to show you several simple commands.

ansible uses ssh to connect remotely to other machines and it is the best option to use ssh keys for passwordless connections

Still, ansible has the option to use also password authentication with “–ask-pass” option. In fact, connecting to the remote host could be done without ssh, but another protocol and this is beyond the scope of this article and it is rarely used.

Ansible modules could be used with different Linux distributions without specifying what kind of packaging software or init system is used.

So when you use module to install a package in your server you may not specify to use apt, yum or any other, or when you want to stop/start/reload/restart a service you do not need to specify it is a systemd or openrc or upstart or sysvinit and so on. The modules gather this information from the currently connected remote host and use the proper command to do its job. Look below in the playbook section.

The inventory file

The first thing to do is your file with servers. In terms of ansible, this is your “inventory file” – the file describing how to connect to your servers like hostname, ports, keys and so on.
The default inventory file is in /etc/ansible/hosts, but you can use file in any location if you include it in the ansible with “-i
So open your favorite text editor and write down your servers (it supports two syntaxes INI and YAML styles):

1) Just enumerate your servers’ hostnames.

Using default port 22 and the user you are logged in. Still, if you use “~/.ssh/config” and you included specific options like port, user, identity file these options will be used by ansible to connect to the hosts.

srv1.example.com
srv2.example.com

Keep on reading!