Operations

Vault Deployment Guide

This deployment guide covers the steps required to install and configure a single HashiCorp Vault cluster as defined in the Vault Reference Architecture.

Below are instructions for installing and configuring Vault on Linux hosts running the systemd system and service manager.

To provide a highly-available single cluster architecture, we recommend Vault be deployed to more than one host, as shown in the Vault Reference Architecture, and connected to a Consul cluster for persistent data storage.

Reference Diagram

» Steps

The below setup steps should be completed on all Vault hosts.

  1. Download Vault
  2. Install Vault
  3. Configure systemd
  4. Configure Consul
  5. Configure Vault
  6. Start Vault

» Step 1: Download Vault

Precompiled Vault binaries are available for download at https://releases.hashicorp.com/vault/ and Vault Enterprise binaries are available for download by following the instructions made available to HashiCorp Vault customers.

You should perform checksum verification of the zip packages using the SHA256SUMS and SHA256SUMS.sig files available for the specific release version. HashiCorp provides a guide on checksum verification for precompiled binaries.

VAULT_VERSION="0.10.3"
curl --silent --remote-name https://releases.hashicorp.com/vault/${VAULT_VERSION}/vault_${VAULT_VERSION}_linux_amd64.zip
curl --silent --remote-name https://releases.hashicorp.com/vault/${VAULT_VERSION}/vault_${VAULT_VERSION}_SHA256SUMS
curl --silent --remote-name https://releases.hashicorp.com/vault/${VAULT_VERSION}/vault_${VAULT_VERSION}_SHA256SUMS.sig

» Step 2: Install Vault

Unzip the downloaded package and move the vault binary to /usr/local/bin/. Check vault is available on the system path.

unzip vault_${VAULT_VERSION}_linux_amd64.zip
sudo chown root:root vault
sudo mv vault /usr/local/bin/
vault --version

The vault command features opt-in autocompletion for flags, subcommands, and arguments (where supported). Enable autocompletion.

vault -autocomplete-install
complete -C /usr/local/bin/vault vault

Give Vault the ability to use the mlock syscall without running the process as root. The mlock syscall prevents memory from being swapped to disk.

sudo setcap cap_ipc_lock=+ep /usr/local/bin/vault

Create a unique, non-privileged system user to run Vault.

sudo useradd --system --home /etc/vault.d --shell /bin/false vault

» Step 3: Configure systemd

Systemd uses documented sane defaults so only non-default values must be set in the configuration file.

Create a Vault service file at /etc/systemd/system/vault.service.

sudo touch /etc/systemd/system/vault.service

Add the below configuration to the Vault service file:

[Unit]
Description="HashiCorp Vault - A tool for managing secrets"
Documentation=https://www.vaultproject.io/docs/
Requires=network-online.target
After=network-online.target
ConditionFileNotEmpty=/etc/vault.d/vault.hcl

[Service]
User=vault
Group=vault
ProtectSystem=full
ProtectHome=read-only
PrivateTmp=yes
PrivateDevices=yes
SecureBits=keep-caps
AmbientCapabilities=CAP_IPC_LOCK
Capabilities=CAP_IPC_LOCK+ep
CapabilityBoundingSet=CAP_SYSLOG CAP_IPC_LOCK
NoNewPrivileges=yes
ExecStart=/usr/local/bin/vault server -config=/etc/vault.d/vault.hcl
ExecReload=/bin/kill --signal HUP $MAINPID
KillMode=process
KillSignal=SIGINT
Restart=on-failure
RestartSec=5
TimeoutStopSec=30
StartLimitIntervalSec=60
StartLimitBurst=3

[Install]
WantedBy=multi-user.target

The following parameters are set for the [Unit] stanza:

  • Description - Free-form string describing the vault service
  • Documentation - Link to the vault documentation
  • Requires - Configure a requirement dependency on the network service
  • After - Configure an ordering dependency on the network service being started before the vault service
  • ConditionFileNotEmpty - Check for a non-zero sized configuration file before vault is started

The following parameters are set for the [Service] stanza:

The following parameters are set for the [Install] stanza:

  • WantedBy - Creates a weak dependency on vault being started by the multi-user run level

» Step 4: Configure Consul

When using Consul as the storage backend for Vault, we recommend using Consul's ACL system to restrict access to the path where Vault stores data. This access restriction is an added security measure in addition to the encryption Vault uses to protect data written to the storage backend.

The Consul website provides documentation on bootstrapping the ACL system, generating a management token and using that token to add some initial tokens for Consul agents, UI access etc. You should complete the bootstrapping section of the Consul documentation before continuing with this guide.

Vault requires a Consul token with specific policy to limit the requests Vault can make to Consul endpoints.

On a host running a Consul agent, and using a Consul management token, create a Consul client token with specific policy for Vault:

CONSUL_TOKEN="6609e426-1aeb-4b0d-c302-3a7568fbc1f9"
curl \
    --request PUT \
    --header "X-Consul-Token: ${CONSUL_TOKEN}" \
    --data \
'{
  "Name": "Vault Token",
  "Type": "client",
  "Rules": "node \"\" { policy = \"write\" } service \"vault\" { policy = \"write\" } agent \"\" { policy = \"write\" }  key \"vault\" { policy = \"write\" } session \"\" { policy = \"write\" } "
}' http://127.0.0.1:8500/v1/acl/create

The response includes the UUID you will use as the token parameter value in Vault's storage stanza configuration. An example response:

{ "ID": "fe3b8d40-0ee0-8783-6cc2-ab1aa9bb16c1" }

» Step 5: Configure Vault

Vault uses documented sane defaults so only non-default values must be set in the configuration file.

Create a configuration file at /etc/vault.d/vault.hcl:

sudo mkdir --parents /etc/vault.d
sudo touch /etc/vault.d/vault.hcl
sudo chown --recursive vault:vault /etc/vault.d
sudo chmod 640 /etc/vault.d/vault.hcl

» Listener stanza

The listener stanza configures the addresses and ports on which Vault will respond to requests.

Add the below configuration to the Vault configuration file:

listener "tcp" {
  address       = "0.0.0.0:8200"
  tls_cert_file = "/path/to/fullchain.pem"
  tls_key_file  = "/path/to/privkey.pem"
}

The following parameters are set for the tcp listener stanza:

  • address (string: "127.0.0.1:8200") – Changing from the loopback address to allow external access to the Vault UI
  • tls_cert_file (string: <required-if-enabled>, reloads-on-SIGHUP) - Must be set when using TLS
  • tls_key_file (string: <required-if-enabled>, reloads-on-SIGHUP) - Must be set when using TLS

More information about tcp listener configuration.

» Seal stanza

This is an ENTERPRISE feature.

If you are deploying Vault Enterprise, you can include seal stanza configuration to specify the seal type to use for additional data protection, such as using HSM or Cloud KMS solutions to encrypt and decrypt the Vault master key. This stanza is optional, and if this is not configured, Vault will use the Shamir algorithm to cryptographically split the master key.

If you are deploying Vault Enterprise, you should review the seal configuration section of our documentation.

An example PKCS #11 compatible HSM example is:

seal "pkcs11" {
  lib            = "/usr/vault/lib/libCryptoki2_64.so"
  slot           = "0"
  pin            = "AAAA-BBBB-CCCC-DDDD"
  key_label      = "vault-hsm-key"
  hmac_key_label = "vault-hsm-hmac-key"
}

» Storage stanza

The storage stanza configures the storage backend, which represents the location for the durable storage of Vault's data.

Add the below configuration to the Vault configuration file:

storage "consul" {
  token = "{{ consul_token }}"
}

The following parameters are set for the consul storage stanza:

  • token (string: "") - Specify the Consul ACL token with permission to read and write from /vault in Consul's key-value store

More information about consul storage configuration.

» Telemetry stanza

The telemetry stanza specifies various configurations for Vault to publish metrics to upstream systems.

If you decide to configure Vault to publish telemtery data, you should review the telemetry configuration section of our documentation.

» Vault UI

Vault features a web-based user interface, allowing you to easily create, read, update, and delete secrets, authenticate, unseal, and more using a graphical user interface, rather than the CLI or API.

Vault should not be deployed in a public internet facing environment, so enabling the Vault UI is typically of benefit to provide a more familiar experience to administrators who are not as comfortable working on the command line, or who do not have alternative access.

Optionally, add the below configuration to the Vault configuration file to enable the Vault UI:

ui = true

More information about configuring the Vault UI.

» Step 6: Start Vault

Enable and start Vault using the systemctl command responsible for controlling systemd managed services. Check the status of the vault service using systemctl.

sudo systemctl enable vault
sudo systemctl start vault
sudo systemctl status vault

» Help and Reference

This deployment guide is designed to work in combination with Vault Reference Architecture. Although not a strict requirement to follow the Vault Reference Architecture, please ensure you are familiar with the overall architecture design; for example installing Vault on multiple physical or virtual (with correct anti-affinity) hosts for high-availability and using Consul for the HA and storage backend.

During the installation of Vault you should also review and apply the recommendations provided in Vault Production Hardening.