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This page explains the cockroach init , which you use to perform a one-time initialization of a new multi-node cluster. For a full tutorial of the cluster startup and initialization process, see one of the tutorials.
When starting a single-node cluster with , you do not need to use the cockroach init command.

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Synopsis

Perform a one-time initialization of a cluster:
View help:

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Flags

The cockroach init command supports the following client connection and logging flags.
cockroach init must target one of the nodes that was listed with when starting the cluster. Otherwise, the command will not initialize the cluster correctly.

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Client connection

FlagDescription
--urlA to use instead of the other arguments. To convert a connection URL to the syntax that works with your client driver, run .

Env Variable: COCKROACH_URL
Default: no URL
--hostThe server host and port number to connect to. This can be the address of any node in the cluster.

Env Variable: COCKROACH_HOST
Default: localhost:26257
--port

-p		The server port to connect to. Note: The port number can also be specified via --host.

Env Variable: COCKROACH_PORT
Default: 26257
--user

-u		The that will own the client session.

Env Variable: COCKROACH_USER
Default: root
--insecureUse an insecure connection.

Env Variable: COCKROACH_INSECURE
Default: false
--cert-principal-mapA comma-separated list of <cert-principal:<db-principal mappings. This allows mapping the principal in a cert to a DB principal such as node or root or any SQL user. This is intended for use in situations where the certificate management system places restrictions on the Subject.CommonName or SubjectAlternateName fields in the certificate (e.g., disallowing a CommonName like node or root). If multiple mappings are provided for the same <cert-principal, the last one specified in the list takes precedence. A principal not specified in the map is passed through as-is via the identity function. A cert is allowed to authenticate a DB principal if the DB principal name is contained in the mapped CommonName or DNS-type SubjectAlternateName fields.
--certs-dirThe path to the containing the CA and client certificates and client key.

Env Variable: COCKROACH_CERTS_DIR
Default: ${HOME}/.cockroach-certs/
--cluster-nameThe cluster name to use to verify the cluster’s identity. If the cluster has a cluster name, you must include this flag. For more information, see .
--disable-cluster-name-verificationDisables the cluster name check for this command. This flag must be paired with --cluster-name. For more information, see .
See for details.

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Logging

By default, this command logs messages to stderr. This includes events with WARNING and higher. If you need to troubleshoot this command’s behavior, you can .

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Examples

Usage of cockroach init assumes that nodes have already been started with and are waiting to be initialized as a new cluster. For a more detailed tutorial, see one of the tutorials.

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Initialize a Cluster on a Node’s Machine

  1. SSH to the machine where the node has been started. This must be a node that was listed with when starting the cluster.
  2. Make sure the client.root.crt and client.root.key files for the root user are on the machine.
  3. Run the cockroach init command with the --certs-dir flag set to the directory containing the ca.crt file and the files for the root user, and with the --host flag set to the address of the current node:
    At this point, all the nodes complete startup and print helpful details to the , such as the CockroachDB version, the URL for the DB Console, and the SQL URL for clients.
  4. SSH to the machine where the node has been started. This must be a node that was listed with when starting the cluster.
  5. Run the cockroach init command with the --host flag set to the address of the current node:
    At this point, all the nodes complete startup and print helpful details to the , such as the CockroachDB version, the URL for the DB Console, and the SQL URL for clients.

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Initialize a cluster from another machine

  1. on a machine separate from the node.
  2. Create a certs directory and copy the CA certificate and the client certificate and key for the root user into the directory.
  3. Run the cockroach init command with the --certs-dir flag set to the directory containing the ca.crt file and the files for the root user, and with the --host flag set to the address of the node. This must be a node that was listed with when starting the cluster:
    At this point, all the nodes complete startup and print helpful details to the , such as the CockroachDB version, the URL for the DB Console, and the SQL URL for clients.
  4. on a machine separate from the node.
  5. Run the cockroach init command with the --host flag set to the address of the node. This must be a node that was listed with when starting the cluster:
    At this point, all the nodes complete startup and print helpful details to the , such as the CockroachDB version, the URL for the DB Console, and the SQL URL for clients.

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See also