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.
This deployment guide is designed to work in combination with the Vault Reference Architecture and Consul Deployment Guide. 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 the Vault Production Hardening guide.
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.
The below setup steps should be completed on all Vault hosts.
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
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
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/
Requires=network-online.target
After=network-online.target
ConditionFileNotEmpty=/etc/vault.d/vault.hcl
[Service]
User=vault
Group=vault
ExecStart=/usr/local/bin/vault server -config=/etc/vault.d/vault.hcl
ExecReload=/bin/kill --signal HUP $MAINPID
KillMode=process
Restart=on-failure
RestartSec=5
[Install]
WantedBy=multi-user.target
The following parameters are set for the [Unit] stanza:
Description- Free-form string describing the vault serviceDocumentation- Link to the vault documentationRequires- Configure a requirement dependency on the network serviceAfter- Configure an ordering dependency on the network service being started before the vault serviceConditionFileNotEmpty- Check for a non-zero sized configuration file before vault is started
The following parameters are set for the [Service] stanza:
User,Group- Run vault as the vault userExecStart- Start vault with theserverargument and path to the configuration fileExecReload- Send vault a HUP signal to trigger a configuration reload in vaultKillMode- Treat vault as a single processRestart- Restart vault unless it returned a clean exit codeRestartSec- Restart vault after 5 seconds of it being considered 'failed'
The following parameters are set for the [Install] stanza:
WantedBy- Creates a weak dependency on vault being started by the multi-user run level
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"}
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
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 UItls_cert_file(string: <required-if-enabled>, reloads-on-SIGHUP)- Must be set when using TLStls_key_file(string: <required-if-enabled>, reloads-on-SIGHUP)- Must be set when using TLS
More information about tcp listener configuration.
~> Vault should always be configured to use TLS to provide secure communication between clients and the Vault cluster. This requires a certificate file and key file be installed on each Linux host running Vault. The certificate file and key file must have permissions allowing the vault user/group to read them.
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"
}
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/vaultin Consul's key-value store
More information about consul storage configuration.
~> Vault should always be configured to use a Consul token with a restrictive ACL policy to read and write from /vault in Consul's key-value store. This follows the principal of least privilege, ensuring Vault is unable to access Consul key-value data stored outside of the /vault path.
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 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.
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
Once running it is important to have a backup and restore strategy for Vault.