This page shows you how to 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.
To deploy a free CockroachDB Cloud cluster instead of running CockroachDB yourself, see the Quickstart.
Before you begin
Requirements
You must have CockroachDB installed locally. This is necessary for generating and managing your deployment's certificates.
You must have SSH access to each machine. This is necessary for distributing and starting CockroachDB binaries.
Your network configuration must allow TCP communication on the following ports:
26257
for intra-cluster and client-cluster communication8080
to expose your DB Console
Carefully review the Production Checklist, including supported hardware and software, and the recommended Topology Patterns.
Do not run multiple node processes on the same VM or machine. This defeats CockroachDB's replication and causes the system to be a single point of failure. Instead, start each node on a separate VM or machine.
To start a node with multiple disks or SSDs, you can use either of these approaches:
- Configure the disks or SSDs as a single RAID volume, then pass the RAID volume to the
--store
flag when starting thecockroach
process on the node. - Provide a separate
--store
flag for each disk when starting thecockroach
process on the node. For more details about stores, see Start a Node.
Warning:If you start a node with multiple--store
flags, it is not possible to scale back down to only using a single store on the node. Instead, you must decommission the node and start a new node with the updated--store
.- Configure the disks or SSDs as a single RAID volume, then pass the RAID volume to the
When starting each node, use the
--locality
flag to describe the node's location, for example,--locality=region=west,zone=us-west-1
. The key-value pairs should be ordered from most to least inclusive, and the keys and order of key-value pairs must be the same on all nodes.When deploying in a single availability zone:
- To be able to tolerate the failure of any 1 node, use at least 3 nodes with the
default
3-way replication factor. In this case, if 1 node fails, each range retains 2 of its 3 replicas, a majority. - To be able to tolerate 2 simultaneous node failures, use at least 5 nodes and increase the
default
replication factor for user data to 5. The replication factor for important internal data is 5 by default, so no adjustments are needed for internal data. In this case, if 2 nodes fail at the same time, each range retains 3 of its 5 replicas, a majority.
- To be able to tolerate the failure of any 1 node, use at least 3 nodes with the
When deploying across multiple availability zones:
- To be able to tolerate the failure of 1 entire AZ in a region, use at least 3 AZs per region and set
--locality
on each node to spread data evenly across regions and AZs. In this case, if 1 AZ goes offline, the 2 remaining AZs retain a majority of replicas. - To ensure that ranges are split evenly across nodes, use the same number of nodes in each AZ. This is to avoid overloading any nodes with excessive resource consumption.
- To be able to tolerate the failure of 1 entire AZ in a region, use at least 3 AZs per region and set
When deploying across multiple regions:
- To be able to tolerate the failure of 1 entire region, use at least 3 regions.
Recommendations
Decide how you want to access your DB Console:
Access Level Description Partially open Set a firewall rule to allow only specific IP addresses to communicate on port 8080
.Completely open Set a firewall rule to allow all IP addresses to communicate on port 8080
.Completely closed Set a firewall rule to disallow all communication on port 8080
. In this case, a machine with SSH access to a node could use an SSH tunnel to access the DB Console.If all of your CockroachDB nodes and clients will run on Droplets in a single region, consider using private networking.
Step 1. Create Droplets
Create Droplets for each node you plan to have in your cluster. If you plan to run a sample workload against the cluster, create a separate Droplet for that workload.
Run at least 3 nodes to ensure survivability.
Use any droplets except standard droplets with only 1 GB of RAM, which is below our minimum requirement. All Digital Ocean droplets use SSD storage.
For more details, see Hardware Recommendations and Cluster Topology.
Step 2. Synchronize clocks
CockroachDB requires moderate levels of clock synchronization to preserve data consistency. For this reason, when a node detects that its clock is out of sync with at least half of the other nodes in the cluster by 80% of the maximum offset allowed (500ms by default), it spontaneously shuts down. This avoids the risk of consistency anomalies, but it's best to prevent clocks from drifting too far in the first place by running clock synchronization software on each node.
ntpd
should keep offsets in the single-digit milliseconds, so that software is featured here, but other methods of clock synchronization are suitable as well.
SSH to the first machine.
Disable
timesyncd
, which tends to be active by default on some Linux distributions:$ sudo timedatectl set-ntp no
Verify that
timesyncd
is off:$ timedatectl
Look for
Network time on: no
orNTP enabled: no
in the output.Install the
ntp
package:$ sudo apt-get install ntp
Stop the NTP daemon:
$ sudo service ntp stop
Sync the machine's clock with Google's NTP service:
$ sudo ntpd -b time.google.com
To make this change permanent, in the
/etc/ntp.conf
file, remove or comment out any lines starting withserver
orpool
and add the following lines:server time1.google.com iburst server time2.google.com iburst server time3.google.com iburst server time4.google.com iburst
Restart the NTP daemon:
$ sudo service ntp start
Note:We recommend Google's NTP service because it handles "smearing" the leap second. If you use a different NTP service that doesn't smear the leap second, be sure to configure client-side smearing in the same way on each machine. See the Production Checklist for details.
Verify that the machine is using a Google NTP server:
$ sudo ntpq -p
The active NTP server will be marked with an asterisk.
Repeat these steps for each machine where a CockroachDB node will run.
Step 3. 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?ready=1
. This health endpoint ensures that load balancers do not direct traffic to nodes that are live but not ready to receive requests.
- 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 4. 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 DB Console
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 5. Generate certificates
You can use cockroach cert
commands, openssl
commands, or Auto TLS cert generation (alpha) to generate security certificates. This section features the cockroach cert
commands.
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 addresses and common names for machines running load balancers.
- A client key pair for the
root
user. You'll use this to run a sample workload against the cluster as well as somecockroach
client commands from your local machine.
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 the load balancer instances:
$ 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> \ <other common names for load balancer instances> \ --certs-dir=certs \ --ca-key=my-safe-directory/ca.key
Upload the CA certificate and node certificate and key to the first node:
$ ssh <username>@<node1 address> "mkdir certs"
$ scp certs/ca.crt \ certs/node.crt \ certs/node.key \ <username>@<node1 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 named
node.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 the load balancer instances:
$ 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> \ <other common names for load balancer instances> \ --certs-dir=certs \ --ca-key=my-safe-directory/ca.key
Upload the CA certificate and node certificate and key to the second node:
$ ssh <username>@<node2 address> "mkdir certs"
$ scp certs/ca.crt \ certs/node.crt \ certs/node.key \ <username>@<node2 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
Upload the CA certificate and client certificate and key to the machine where you will run a sample workload:
$ ssh <username>@<workload address> "mkdir certs"
$ scp certs/ca.crt \ certs/client.root.crt \ certs/client.root.key \ <username>@<workload address>:~/certs
In later steps, you'll also use the
root
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.
On accessing the DB Console in a later step, your browser will consider the CockroachDB-created certificate invalid and you’ll need to click through a warning message to get to the UI. You can avoid this issue by using a certificate issued by a public CA.
Step 6. Start nodes
You can start the nodes manually or automate the process using systemd.
For each initial node of your cluster, complete the following steps:
After completing these steps, nodes will not yet be live. They will complete the startup process and join together to form a cluster as soon as the cluster is initialized in the next step.
Visit Releases and download the full binary of CockroachDB to the node.
On the node, follow the instructions to install CockroachDB.
Run the
cockroach start
command:$ cockroach start \ --certs-dir=certs \ --advertise-addr=<node1 address> \ --join=<node1 address>,<node2 address>,<node3 address> \ --cache=.25 \ --max-sql-memory=.25 \ --background
This command primes the node to start, using the following flags:
Flag Description --certs-dir
Specifies the directory where you placed the ca.crt
file and thenode.crt
andnode.key
files for the node.--advertise-addr
Specifies the IP address/hostname and port to tell other nodes to use. The port number can be omitted, in which case it defaults to 26257
.
This value must route to an IP address the node is listening on (with--listen-addr
unspecified, the node listens on all IP addresses).
In some networking scenarios, you may need to use--advertise-addr
and/or--listen-addr
differently. For more details, see Networking.--join
Identifies the address of 3-5 of the initial nodes of the cluster. These addresses should match the addresses that the target nodes are advertising. --cache
--max-sql-memory
Increases the node's cache size to 25% of available system memory to improve read performance. The capacity for in-memory SQL processing defaults to 25% of system memory but can be raised, if necessary, to increase the number of simultaneous client connections allowed by the node as well as the node's capacity for in-memory processing of rows when using ORDER BY
,GROUP BY
,DISTINCT
, joins, and window functions. For more details, see Cache and SQL Memory Size.--background
Starts the node in the background so you gain control of the terminal to issue more commands. When deploying across multiple datacenters, or when there is otherwise high latency between nodes, it is recommended to set
--locality
as well. For more details, see Locality.For other flags not explicitly set, the command uses default values. For example, the node stores data in
--store=cockroach-data
and binds DB Console HTTP requests to--http-addr=<node1 address>:8080
. To set these options manually, see Start a Node.
Repeat these steps for each additional node that you want in your cluster.
For each initial node of your cluster, complete the following steps:
After completing these steps, nodes will not yet be live. They will complete the startup process and join together to form a cluster as soon as the cluster is initialized in the next step.
SSH to the machine where you want the node to run. Ensure you are logged in as the
root
user.Download the CockroachDB archive for Linux, and extract the binary:
$ curl https://binaries.cockroachdb.com/cockroach-v23.2.16.linux-amd64.tgz \ | tar -xz
Copy the binary into the
PATH
:$ cp -i cockroach-v23.2.16.linux-amd64/cockroach /usr/local/bin/
If you get a permissions error, prefix the command with
sudo
.CockroachDB uses custom-built versions of the GEOS libraries. Copy these libraries to the location where CockroachDB expects to find them:
$ mkdir -p /usr/local/lib/cockroach
$ cp -i cockroach-v23.2.16.linux-amd64/lib/libgeos.so /usr/local/lib/cockroach/
$ cp -i cockroach-v23.2.16.linux-amd64/lib/libgeos_c.so /usr/local/lib/cockroach/
If you get a permissions error, prefix the command with
sudo
.Create the Cockroach directory:
$ mkdir /var/lib/cockroach
Create a Unix user named
cockroach
:$ useradd cockroach
Move the
certs
directory to thecockroach
directory.$ mv certs /var/lib/cockroach/
Change the ownership of the
cockroach
directory to the usercockroach
:$ chown -R cockroach /var/lib/cockroach
Download the sample configuration template and save the file in the
/etc/systemd/system/
directory:curl -o securecockroachdb.service https://raw.githubusercontent.com/cockroachdb/docs/main/src/current/_includes/v23.2/prod-deployment/securecockroachdb.service
Alternatively, you can create the file yourself and copy the script into it:
[Unit] Description=Cockroach Database cluster node Requires=network.target [Service] Type=notify WorkingDirectory=/var/lib/cockroach ExecStart=/usr/local/bin/cockroach start --certs-dir=certs --advertise-addr=<node1 address> --join=<node1 address>,<node2 address>,<node3 address> --cache=.25 --max-sql-memory=.25 TimeoutStopSec=300 Restart=always RestartSec=10 StandardOutput=syslog StandardError=syslog SyslogIdentifier=cockroach User=cockroach [Install] WantedBy=default.target
In the sample configuration template, specify values for the following flags:
Flag Description --advertise-addr
Specifies the IP address/hostname and port to tell other nodes to use. The port number can be omitted, in which case it defaults to 26257
.
This value must route to an IP address the node is listening on (with--listen-addr
unspecified, the node listens on all IP addresses).
In some networking scenarios, you may need to use--advertise-addr
and/or--listen-addr
differently. For more details, see Networking.--join
Identifies the address of 3-5 of the initial nodes of the cluster. These addresses should match the addresses that the target nodes are advertising. When deploying across multiple datacenters, or when there is otherwise high latency between nodes, it is recommended to set
--locality
as well. For more details, see Locality.For other flags not explicitly set, the command uses default values. For example, the node stores data in
--store=cockroach-data
and binds DB Console HTTP requests to--http-addr=localhost:8080
. To set these options manually, see Start a Node.Start the CockroachDB cluster:
$ systemctl start securecockroachdb
Configure
systemd
to start CockroachDB automatically after a reboot:systemctl enable securecockroachdb
Repeat these steps for each additional node that you want in your cluster.
systemd
handles node restarts in case of node failure. To stop a node without systemd
restarting it, run systemctl stop securecockroachdb
Step 7. Initialize the cluster
On your local machine, run the cockroach init
command to complete the node startup process and have them join together as a cluster:
$ cockroach init --certs-dir=certs --host=<address of any node on --join list>
After running this command, each node prints helpful details to the standard output, such as the CockroachDB version, the URL for the DB Console, and the SQL URL for clients.
Step 8. Test the cluster
CockroachDB replicates and distributes data behind-the-scenes and uses a Gossip protocol to enable each node to locate data across the cluster. Once a cluster is live, any node can be used as a SQL gateway.
When using a load balancer, you should issue commands directly to the load balancer, which then routes traffic to the nodes.
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 address of the load balancer:$ cockroach sql --certs-dir=certs --host=<address of load balancer>
Create a
securenodetest
database:> CREATE DATABASE securenodetest;
View the cluster's databases, which will include
securenodetest
:> SHOW DATABASES;
+--------------------+ | Database | +--------------------+ | crdb_internal | | information_schema | | securenodetest | | pg_catalog | | system | +--------------------+ (5 rows)
Use
\q
to exit the SQL shell.
Step 9. Run a sample workload
CockroachDB comes with a number of built-in workloads for simulating client traffic. This step features CockroachDB's version of the TPC-C workload.
Be sure that you have configured your network to allow traffic from the application to the load balancer. In this case, you will run the sample workload on one of your machines. The traffic source should therefore be the internal (private) IP address of that machine.
For comprehensive guidance on benchmarking CockroachDB with TPC-C, refer to Performance Benchmarking.
SSH to the machine where you want to run the sample TPC-C workload.
This should be a machine that is not running a CockroachDB node, and it should already have a
certs
directory containingca.crt
,client.root.crt
, andclient.root.key
files.Download the CockroachDB archive for Linux, and extract the binary:
$ curl https://binaries.cockroachdb.com/cockroach-v23.2.16.linux-amd64.tgz \ | tar -xz
Copy the binary into the
PATH
:$ cp -i cockroach-v23.2.16.linux-amd64/cockroach /usr/local/bin/
If you get a permissions error, prefix the command with
sudo
.Use the
cockroach workload
command to load the initial schema and data, pointing it at the IP address of the load balancer:$ cockroach workload init tpcc \ 'postgresql://root@<IP ADDRESS OF LOAD BALANCER>:26257/tpcc?sslmode=verify-full&sslrootcert=certs/ca.crt&sslcert=certs/client.root.crt&sslkey=certs/client.root.key'
Use the
cockroach workload
command to run the workload for 10 minutes:$ cockroach workload run tpcc \ --duration=10m \ 'postgresql://root@<IP ADDRESS OF LOAD BALANCER>:26257/tpcc?sslmode=verify-full&sslrootcert=certs/ca.crt&sslcert=certs/client.root.crt&sslkey=certs/client.root.key'
You'll see per-operation statistics print to standard output every second:
_elapsed___errors__ops/sec(inst)___ops/sec(cum)__p50(ms)__p95(ms)__p99(ms)_pMax(ms) 1s 0 1443.4 1494.8 4.7 9.4 27.3 67.1 transfer 2s 0 1686.5 1590.9 4.7 8.1 15.2 28.3 transfer 3s 0 1735.7 1639.0 4.7 7.3 11.5 28.3 transfer 4s 0 1542.6 1614.9 5.0 8.9 12.1 21.0 transfer 5s 0 1695.9 1631.1 4.7 7.3 11.5 22.0 transfer 6s 0 1569.2 1620.8 5.0 8.4 11.5 15.7 transfer 7s 0 1614.6 1619.9 4.7 8.1 12.1 16.8 transfer 8s 0 1344.4 1585.6 5.8 10.0 15.2 31.5 transfer 9s 0 1351.9 1559.5 5.8 10.0 16.8 54.5 transfer 10s 0 1514.8 1555.0 5.2 8.1 12.1 16.8 transfer ...
After the specified duration (10 minutes in this case), the workload will stop and you'll see totals printed to standard output:
_elapsed___errors_____ops(total)___ops/sec(cum)__avg(ms)__p50(ms)__p95(ms)__p99(ms)_pMax(ms)__result 600.0s 0 823902 1373.2 5.8 5.5 10.0 15.2 209.7
Tip:For more
tpcc
options, usecockroach workload run tpcc --help
. For details about other workloads built into thecockroach
binary, usecockroach workload --help
.To monitor the load generator's progress, open the DB Console by pointing a browser to the address in the
admin
field in the standard output of any node on startup.Since the load generator is pointed at the load balancer, the connections will be evenly distributed across nodes. To verify this, click Metrics on the left, select the SQL dashboard, and then check the SQL Connections graph. You can use the Graph menu to filter the graph for specific nodes.
Step 10. Monitor the cluster
Despite CockroachDB's various built-in safeguards against failure, it is critical to actively monitor the overall health and performance of a cluster running in production and to create alerting rules that promptly send notifications when there are events that require investigation or intervention.
For details about available monitoring options and the most important events and metrics to alert on, see Monitoring and Alerting.
Step 11. Scale the cluster
You can start the nodes manually or automate the process using systemd.
For each additional node you want to add to the cluster, complete the following steps:
SSH to the machine where you want the node to run.
Download the CockroachDB archive for Linux, and extract the binary:
curl -o cockroach-v23.2.16.linux-amd64.tgz https://binaries.cockroachdb.com/cockroach-v23.2.16.linux-amd64.tgz; tar xzvf cockroach-v23.2.16.linux-amd64.tgz
Copy the binary into the
PATH
:$ cp -i cockroach-v23.2.16.linux-amd64/cockroach /usr/local/bin/
If you get a permissions error, prefix the command with
sudo
.Run the
cockroach start
command, passing the new node's address as the--advertise-addr
flag and pointing--join
to the three existing nodes (also include--locality
if you set it earlier).$ cockroach start \ --certs-dir=certs \ --advertise-addr=<node4 address> \ --join=<node1 address>,<node2 address>,<node3 address> \ --cache=.25 \ --max-sql-memory=.25 \ --background
Update your load balancer to recognize the new node.
For each additional node you want to add to the cluster, complete the following steps:
SSH to the machine where you want the node to run. Ensure you are logged in as the
root
user.Download the CockroachDB archive for Linux, and extract the binary:
$ curl https://binaries.cockroachdb.com/cockroach-v23.2.16.linux-amd64.tgz \ | tar -xz
Copy the binary into the
PATH
:$ cp -i cockroach-v23.2.16.linux-amd64/cockroach /usr/local/bin/
If you get a permissions error, prefix the command with
sudo
.Create the Cockroach directory:
$ mkdir /var/lib/cockroach
Create a Unix user named
cockroach
:$ useradd cockroach
Move the
certs
directory to thecockroach
directory.$ mv certs /var/lib/cockroach/
Change the ownership of the
cockroach
directory to the usercockroach
:$ chown -R cockroach /var/lib/cockroach
Download the sample configuration template:
curl -o securecockroachdb.service https://raw.githubusercontent.com/cockroachdb/docs/master/_includes/v23.2/prod-deployment/securecockroachdb.service
Alternatively, you can create the file yourself and copy the script into it:
[Unit] Description=Cockroach Database cluster node Requires=network.target [Service] Type=notify WorkingDirectory=/var/lib/cockroach ExecStart=/usr/local/bin/cockroach start --certs-dir=certs --advertise-addr=<node1 address> --join=<node1 address>,<node2 address>,<node3 address> --cache=.25 --max-sql-memory=.25 TimeoutStopSec=300 Restart=always RestartSec=10 StandardOutput=syslog StandardError=syslog SyslogIdentifier=cockroach User=cockroach [Install] WantedBy=default.target
Save the file in the
/etc/systemd/system/
directory.Customize the sample configuration template for your deployment:
Specify values for the following flags in the sample configuration template:
Flag Description --advertise-addr
Specifies the IP address/hostname and port to tell other nodes to use. The port number can be omitted, in which case it defaults to 26257
.
This value must route to an IP address the node is listening on (with--listen-addr
unspecified, the node listens on all IP addresses).
In some networking scenarios, you may need to use--advertise-addr
and/or--listen-addr
differently. For more details, see Networking.--join
Identifies the address of 3-5 of the initial nodes of the cluster. These addresses should match the addresses that the target nodes are advertising. Repeat these steps for each additional node that you want in your cluster.
Step 12. 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 load balancer, not to a CockroachDB node.
- Take backups of your data.
You may also want to adjust the way the cluster replicates data. For example, by default, a multi-node cluster replicates all data 3 times; you can change this replication factor or create additional rules for replicating individual databases and tables differently. For more information, see Replication Controls.
When running a cluster of 5 nodes or more, it's safest to increase the replication factor for important internal data to 5, even if you do not do so for user data. For the cluster as a whole to remain available, the ranges for this internal data must always retain a majority of their replicas.