--- layout: docs page_title: Zookeeper - Storage Backends - Configuration sidebar_title: Zookeeper description: The Zookeeper storage backend is used to persist Vault's data in Zookeeper. --- # Zookeeper Storage Backend The Zookeeper storage backend is used to persist Vault's data in [Zookeeper][zk]. - **High Availability** – the Zookeeper storage backend supports high availability. - **Community Supported** – the Zookeeper storage backend is supported by the community. While it has undergone review by HashiCorp employees, they may not be as knowledgeable about the technology. If you encounter problems with them, you may be referred to the original author. ```hcl storage "zookeeper" { address = "localhost:2181" path = "vault/" } ``` ## `zookeeper` Parameters - `address` `(string: "localhost:2181")` – Specifies the addresses of the Zookeeper instances as a comma-separated list. - `path` `(string: "vault/")` – Specifies the path in Zookeeper where data will be stored. The following optional settings can be used to configure zNode ACLs: ~> **Warning!** If neither `auth_info` nor `znode_owner` are set, the backend will not authenticate with Zookeeper and will set the `OPEN_ACL_UNSAFE` ACL on all nodes. In this scenario, anyone connected to Zookeeper could change Vault’s znodes and, potentially, take Vault out of service. - `auth_info` `(string: "")` – Specifies an authentication string in Zookeeper AddAuth format. For example, `digest:UserName:Password` could be used to authenticate as user `UserName` using password `Password` with the `digest` mechanism. - `znode_owner` `(string: "")` – If specified, Vault will always set all permissions (CRWDA) to the ACL identified here via the Schema and User parts of the Zookeeper ACL format. The expected format is `schema:user-ACL-match`, for example: ```text # Access for user "UserName" with corresponding digest "HIDfRvTv623G==" digest:UserName:HIDfRvTv623G== ``` ```text # Access from localhost only ip:127.0.0.1 ``` ```text # Access from any host on the 70.95.0.0 network (Zookeeper 3.5+) ip:70.95.0.0/16 ``` - `tls_enabled` `(bool: false)` – Specifies if TLS communication with the Zookeeper backend has to be enabled. - `tls_ca_file` `(string: "")` – Specifies the path to the CA certificate file used for Zookeeper communication. Multiple CA certificates can be provided in the same file. - `tls_cert_file` `(string: "")` (optional) – Specifies the path to the client certificate for Zookeeper communication. - `tls_key_file` `(string: "")` – Specifies the path to the private key for Zookeeper communication. - `tls_min_version` `(string: "tls12")` – Specifies the minimum TLS version to use. Accepted values are `"tls10"`, `"tls11"`, `"tls12"` or `"tls13"`. - `tls_skip_verify` `(bool: false)` – Disable verification of TLS certificates. Using this option is highly discouraged. - `tls_verify_ip` `(bool: false)` - This property comes into play only when 'tls_skip_verify' is set to false. When 'tls_verify_ip' is set to 'true', the zookeeper server's IP is verified in the presented certificates CN/SAN entry. When set to 'false' the server's DNS name is verified in the certificates CN/SAN entry. ## `zookeeper` Examples ### Custom Address and Path This example shows configuring Vault to communicate with a Zookeeper installation running on a custom port and to store data at a custom path. ```hcl storage "zookeeper" { address = "localhost:3253" path = "my-vault-data/" } ``` ### zNode Vault User Only This example instructs Vault to set an ACL on all of its zNodes which permit access only to the user "vaultUser". As per Zookeeper's ACL model, the digest value in `znode_owner` must match the user in `znode_owner`. ```hcl storage "zookeeper" { znode_owner = "digest:vaultUser:raxgVAfnDRljZDAcJFxznkZsExs=" auth_info = "digest:vaultUser:abc" } ``` ### zNode Localhost Only This example instructs Vault to only allow access from localhost. As this is the `ip` no `auth_info` is required since Zookeeper uses the address of the client for the ACL check. ```hcl storage "zookeeper" { znode_owner = "ip:127.0.0.1" } ``` ### zNode connection over TLS. This example instructs Vault to connect to Zookeeper using the provided TLS configuration. The host verification will happen with the presented certificate using the servers IP because 'tls_verify_ip' is set to true. ```hcl storage "zookeeper" { address = "host1.com:5200,host2.com:5200,host3.com:5200" path = "vault_path_on_zk/" znode_owner = "digest:vault_user:digestvalueforpassword=" auth_info = "digest:vault_user:thisisthepassword" redirect_addr = "http://localhost:8200" tls_verify_ip = "true" tls_enabled= "true" tls_min_version= "tls12" tls_cert_file = "/path/to/the/cert/file/zkcert.pem" tls_key_file = "/path/to/the/key/file/zkkey.pem" tls_skip_verify= "false" tls_ca_file= "/path/to/the/ca/file/ca.pem" } ``` [zk]: https://zookeeper.apache.org/