Configure Vault for Storing Secrets

HashiCorp’s Vault is a popular solution for storing secrets. While F5 NGINX Management Suite provides encryption-at-rest for secrets stored on disk, if you have an existing Vault installation, you may prefer to store all secrets in one place. NGINX Management Suite provides a driver you can use to connect to existing Vault installations and store secrets.

Before You Begin

To complete the steps in this guide, you need the following:

• A working understanding of Vault and its operations
• A running version of Vault 1.8.8 or later

Create Periodic Service Tokens

Access to a vault requires a renewable token.

Note:
If you attempt to use the vault’s Root Token, NGINX Management Suite will not be able to start the secrets driver, as that token is not renewable.

To create a periodic service token for NGINX Management Suite, take the following steps:

1. Use the Vault user interface to create a new policy.

   The “default” policy has no access to store or retrieve secrets, and the root policy is too broad. We recommend creating a policy called nms_secrets with these capabilities:

   path "secret/*" {
     capabilities = ["create", "read", "update", "delete", "list"]
   }
   

2. Create an initial service token that will last so long as it’s renewed on time until it’s manually revoked. We recommend a period of 24 hours, which is used in the following example. NGINX Management Suite will always attempt to renew tokens before expiring, so shorter times also work.

   To create a token, take the following step, substituting your vault’s Root Token for $VAULT_ROOT_TOKEN and your vault’s address for $VAULT_ADDR:

   curl -X POST --header "X-Vault-Token: $VAULT_ROOT_TOKEN" \
     --data '{"policies": "nms_secrets", "period": "24h"}' \
     $VAULT_ADDR/v1/auth/token/create | jq -r ".auth.client_token" > periodic_token.txt
   

3. Verify your token works:

   curl --header "X-Vault-Token: $(cat periodic_token.txt)" \
     $VAULT_ADDR/v1/auth/token/lookup-self | jq .data
   

4. If everything looks good, stop the nms-core service and configure NGINX Management Suite to use your token:

   sudo systemctl stop nms-core
   sudo NMS_VAULT_TOKEN=$(cat periodic_token.txt) nms-core secret vault-token
   sudo systemctl restart nms-core
   

Start Using Vault to Store Secrets

1. To use the new token on the NGINX Management Suite server, open the /etc/nms/nms.conf file for editing.

2. Update the secrets section indented under core to tell NGINX Management Suite how to handle secrets.

   For example, an internal development installation of Vault might use:

   secrets:
     # change driver to "local" if you want to stop using vault
     driver: vault
     config:
       # local file path for stored secrets when using the local driver
       path: /var/lib/nms/secrets
       # key_file is required for local driver
       key_file: /var/lib/nms/secrets/key
       # vault address for when using the vault driver
       address: http://127.0.0.1:8200/v1
       # isolation is used to store secrets in a specific namespace and prefix to better restrict access rights
       # on the local file system or shared vault server.
       isolation:
         namespace: secret
         prefix: secureString
   

3. Save the changes and close the file.

4. Restart the NGINX Management Suite services to start using Vault to store secrets:

   sudo systemctl restart nms
   

Switching between Vault and Local Encryption

After you’ve set up Vault to store your secrets, you can easily switch between local encryption and Vault as desired.

Switch to Local Encryption

To switch from using Vault to local disk encryption, take the following steps:

1. Stop NGINX Management Suite to ensure exclusive access to the secrets:

   sudo systemctl stop nms
   

2. Run the following command to migrate secrets from Vault to your local disk:

   sudo nms-core secret migrate-secrets-to-local
   

3. Update the core/secrets/driver line from /etc/nms/nms.conf, which you added in the previous section, to say driver: local.

4. Restart NGINX Management Suite:

   sudo systemctl start nms
   

Switch to Vault

To switch from using local encryption back to Vault, take the following steps:

1. Stop NGINX Management Suite to ensure exclusive access to the secrets:

   sudo systemctl stop nms
   

2. Run the following command to migrate secrets from your local disk to Vault:

   sudo nms-core secret migrate-secrets-to-vault
   

3. Update the core/secrets/driver line from /etc/nms/nms.conf, which you added in the previous section, to say driver: vault.

4. Restart NGINX Management Suite:

   sudo systemctl start nms
   

Troubleshooting