This page shows you how to manually deploy a secure multi-node CockroachDB cluster on Digital Ocean, using Digital Ocean's managed load balancing service to distribute client traffic.
If you are only testing CockroachDB, or you are not concerned with protecting network communication with TLS encryption, you can use an insecure cluster instead. Select Insecure above for instructions.
Requirements
Locally, you must have CockroachDB installed, which you’ll use to generate and manage your deployment’s certificates.
In Digitial Ocean, you must have SSH access to each Droplet with root or sudo privileges. This is necessary for distributing binaries and starting CockroachDB.
Recommendations
For guidance on cluster topology, clock synchronization, and file descriptor limits, see Recommended Production Settings.
Set up your Droplets using private networking.
Decide how you want to access your Admin UI:
- Only from specific IP addresses, which requires you to set firewall rules to allow communication on port
8080
(documented on this page). - Using an SSH tunnel, which requires you to use
--http-host=localhost
when starting your nodes.
- Only from specific IP addresses, which requires you to set firewall rules to allow communication on port
Step 1. Create Droplets
Create Droplets with private networking for each node you plan to have in your cluster. We recommend:
- Running at least 3 nodes to ensure survivability.
- Selecting the same continent for all of your Droplets for best performance.
Step 2. Set up load balancing
Each CockroachDB node is an equally suitable SQL gateway to your cluster, but to ensure client performance and reliability, it's important to use load balancing:
Performance: Load balancers spread client traffic across nodes. This prevents any one node from being overwhelmed by requests and improves overall cluster performance (queries per second).
Reliability: Load balancers decouple client health from the health of a single CockroachDB node. In cases where a node fails, the load balancer redirects client traffic to available nodes.
Digital Ocean offers fully-managed load balancers to distribute traffic between Droplets.
- Create a Digital Ocean Load Balancer. Be sure to:
- Set forwarding rules to route TCP traffic from the load balancer's port 26257 to port 26257 on the node Droplets.
- Configure health checks to use HTTP port 8080 and path
/health
.
- Note the provisioned IP Address for the load balancer. You'll use this later to test load balancing and to connect your application to the cluster.
Step 3. Configure your network
Set up a firewall for each of your Droplets, allowing TCP communication on the following two ports:
- 26257 (
tcp:26257
) for inter-node communication (i.e., working as a cluster), for applications to connect to the load balancer, and for routing from the load balancer to nodes - 8080 (
tcp:8080
) for exposing your Admin UI
For guidance, you can use Digital Ocean's guide to configuring firewalls based on the Droplet's OS:
- Ubuntu and Debian can use
ufw
. - FreeBSD can use
ipfw
. - Fedora can use
iptables
. - CoreOS can use
iptables
. - CentOS can use
firewalld
.
Step 4. Generate certificates
Locally, you'll need to create the following certificates and keys:
- A certificate authority (CA) key pair (
ca.crt
andca.key
). - A node key pair for each node, issued to its IP addresses and any common names the machine uses, as well as to the IP address provisioned for the Digital Ocean Load Balancer.
- A client key pair for the
root
user.
Install CockroachDB on your local machine, if you haven't already.
Create two directories:
$ mkdir certs
$ mkdir my-safe-directory
certs
: You'll generate your CA certificate and all node and client certificates and keys in this directory and then upload some of the files to your nodes.my-safe-directory
: You'll generate your CA key in this directory and then reference the key when generating node and client certificates. After that, you'll keep the key safe and secret; you will not upload it to your nodes.
Create the CA certificate and key:
$ cockroach cert create-ca \ --certs-dir=certs \ --ca-key=my-safe-directory/ca.key
Create the certificate and key for the first node, issued to all common names you might use to refer to the node as well as to addresses provisioned for the Digital Ocean Load Balancer:
<node internal IP address>
, which is the node Droplet's Private IP.<node external IP address>
, which is the node Droplet's ipv4 address.<node hostname>
, which is the node Droplet's Name.<other common names for node>
, which include any domain names you point to the node Droplet.localhost
and127.0.0.1
<load balancer IP address>
, which is the Digital Ocean Load Balancer's provisioned IP Address.<load balancer hostname>
, which is the Digital Ocean Load Balancer's Name.
$ cockroach cert create-node \ <node1 internal IP address> \ <node1 external IP address> \ <node1 hostname> \ <other common names for node1> \ localhost \ 127.0.0.1 \ <load balancer IP address> \ <load balancer hostname> \ --certs-dir=certs \ --ca-key=my-safe-directory/ca.key
Upload certificates to the first node:
# Create the certs directory: $ ssh <username>@<node1 external IP address> "mkdir certs"
# Upload the CA certificate and node certificate and key: $ scp certs/ca.crt \ certs/node.crt \ certs/node.key \ <username>@<node1 external IP address>:~/certs
Delete the local copy of the node certificate and key:
$ rm certs/node.crt certs/node.key
Note:This is necessary because the certificates and keys for additional nodes will also be namednode.crt
andnode.key
As an alternative to deleting these files, you can run the nextcockroach cert create-node
commands with the--overwrite
flag.Create the certificate and key for the second node, issued to all common names you might use to refer to the node as well as to addresses provisioned for the Digital Ocean Load Balancer:
$ cockroach cert create-node \ <node2 internal IP address> \ <node2 external IP address> \ <node2 hostname> \ <other common names for node2> \ localhost \ 127.0.0.1 \ <load balancer IP address> \ <load balancer hostname> \ --certs-dir=certs \ --ca-key=my-safe-directory/ca.key
Upload certificates to the second node:
# Create the certs directory: $ ssh <username>@<node2 external IP address> "mkdir certs"
# Upload the CA certificate and node certificate and key: $ scp certs/ca.crt \ certs/node.crt \ certs/node.key \ <username>@<node2 external IP address>:~/certs
Repeat steps 6 - 8 for each additional node.
Create a client certificate and key for the
root
user:$ cockroach cert create-client \ root \ --certs-dir=certs \ --ca-key=my-safe-directory/ca.key
Tip:In later steps, you'll use theroot
user's certificate to runcockroach
client commands from your local machine. If you might also want to runcockroach
client commands directly on a node (e.g., for local debugging), you'll need to copy theroot
user's certificate and key to that node as well.
Step 5. Start the first node
SSH to your Droplet:
$ ssh <username>@<node1 external IP address>
Install the latest CockroachDB binary:
# Get the latest CockroachDB tarball. $ curl https://binaries.cockroachdb.com/cockroach-v1.0.7.linux-amd64.tgz
# Extract the binary. $ tar -xzf cockroach-v1.0.7.linux-amd64.tgz \ --strip=1 cockroach-v1.0.7.linux-amd64/cockroach
# Move the binary. $ sudo mv cockroach /usr/local/bin/
Start a new CockroachDB cluster with a single node, specifying the location of certificates and the address at which other nodes can reach it:
$ cockroach start --background \ --certs-dir=certs \ --advertise-host=<node1 internal IP address>
Step 6. Add nodes to the cluster
At this point, your cluster is live and operational but contains only a single node. Next, scale your cluster by setting up additional nodes that will join the cluster.
SSH to your Droplet:
$ ssh <username>@<additional node external IP address>
Install the latest CockroachDB binary:
# Get the latest CockroachDB tarball. $ curl https://binaries.cockroachdb.com/cockroach-v1.0.7.linux-amd64.tgz
# Extract the binary. $ tar -xzf cockroach-v1.0.7.linux-amd64.tgz \ --strip=1 cockroach-v1.0.7.linux-amd64/cockroach
# Move the binary. $ sudo mv cockroach /usr/local/bin/
Start a new node that joins the cluster using the first node's internal IP address:
$ cockroach start --background \ --certs-dir=certs \ --advertise-host=<node internal IP address> \ --join=<node1 internal IP address>:26257
Repeat these steps for each Droplet you want to use as a node.
Step 7. Test your cluster
CockroachDB replicates and distributes data for you behind-the-scenes and uses a Gossip protocol to enable each node to locate data across the cluster.
To test this, use the built-in SQL client locally as follows:
On your local machine, connect the built-in SQL client to node 1, with the
--host
flag set to the address of node 1 and security flags pointing to the CA cert and the client cert and key:$ cockroach sql \ --certs-dir=certs \ --host=<node1 address>
Create a
securenodetest
database:> CREATE DATABASE securenodetest;
Use CTRL-D, CTRL-C, or
\q
to exit the SQL shell.Connect the built-in SQL client to node 2, with the
--host
flag set to the address of node 2 and security flags pointing to the CA cert and the client cert and key:$ cockroach sql \ --certs-dir=certs \ --host=<node2 address>
View the cluster's databases, which will include
securenodetest
:> SHOW DATABASES;
+--------------------+ | Database | +--------------------+ | crdb_internal | | information_schema | | securenodetest | | pg_catalog | | system | +--------------------+ (5 rows)
Use CTRL-D, CTRL-C, or
\q
to exit the SQL shell.
Step 8. Test load balancing
The Digital Ocean Load Balancer created in step 2 can serve as the client gateway to the cluster. Instead of connecting directly to a CockroachDB node, clients can connect to the load balancer, which will then redirect the connection to a CockroachDB node.
To test this, use the built-in SQL client locally as follows:
On your local machine, launch the built-in SQL client, with the
--host
flag set to the load balancer's IP address and security flags pointing to the CA cert and the client cert and key:$ cockroach sql \ --certs-dir=certs \ --host=<load balancer IP address>
View the cluster's databases:
> SHOW DATABASES;
+--------------------+ | Database | +--------------------+ | crdb_internal | | information_schema | | securenodetest | | pg_catalog | | system | +--------------------+ (5 rows)
As you can see, the load balancer redirected the query to one of the CockroachDB nodes.
Check which node you were redirected to:
> SELECT node_id FROM crdb_internal.node_build_info LIMIT 1;
+---------+ | node_id | +---------+ | 3 | +---------+ (1 row)
Use CTRL-D, CTRL-C, or
\q
to exit the SQL shell.
Step 9. Monitor the cluster
View your cluster's Admin UI by going to https://<any node's external IP address>:8080
.
On this page, verify that the cluster is running as expected:
Click View nodes list on the right to ensure that all of your nodes successfully joined the cluster.
Also check the Replicas column. If you have nodes with 0 replicas, it's possible you didn't properly set the
--advertise-host
flag to the Droplet's internal IP address. This prevents the node from receiving replicas and working as part of the cluster.Click the Databases tab on the left to verify that
securenodetest
is listed.
Step 10. Use the database
Now that your deployment is working, you can:
- Implement your data model.
- Create users and grant them privileges.
- Connect your application. Be sure to connect your application to the Digital Ocean Load Balancer, not to a CockroachDB node.