Knowledge Base

How to set up SSL communcation when running Neo4j within a Docker Container

Neo4j 3.2 added a Unified SSL Framework to setup secure connections for Bolt, HTTPS and Intra-Cluster Encryption. Details on this framework can be found at:

Setting up secure Bolt and HTTPS communications when running Neo4j within a Docker Container requires some specific steps and configuration settings.

The below steps assume the processes outlined in the above documentation link have been followed. In addition, public certificates and private keys have already been created.

The steps listed below are for example purposes only. It must be made sure these are suitable for the environment before deployment.

The configuration steps for Neo4j 3.5 and Neo4j 4.x are different. Both are listed below.

Neo4j 4.x

1. Create Neo4j Scope Directory Structure

Neo4j 4.x requires directories are created with a specific structure. The following is an example for https and bolt scopes

├── bolt
│   ├── revoked
│   └── trusted
└── https
    ├── revoked
    └── trusted

Create the above directory structure in $HOME/neo4j. It is possible to use any directory of your choice, making sure to adjust the below paths accordingly.

2. Copy SSL Certificates and Correct Permissions

A copy of the public certificate and private key files will need to be placed in each scopes directory. The public key will also need to be copied into the respective scopes trusted directory.

Once copied, the directory and file layout in $HOME/neo4j/ssl should look like the following:

├── bolt
│   ├── private.key
│   ├── public.crt
│   ├── revoked
│   └── trusted
│       └── public.crt
└── https
    ├── private.key
    ├── public.crt
    ├── revoked
    └── trusted
        └── public.crt

The container will run Neo4j as user neo4j. The uid and gid is 7474. Use the following command to adjust the permissions on the ssl directory:

sudo chgrp -R 7474 $HOME/neo4j/ssl && \
sudo chmod -R g+rx $HOME/neo4j/ssl

3. Configure Neo4j

There are two approaches for configuring Neo4j running as a Docker container: externalize neo4j.conf using Docker host volumes, OR configure Docker environment variables. You should only choose one of the approaches (not both)

Externalize neo4j.conf

It is possible to use a Docker host volume to mount a neo4j.conf file. This is achieved by mounting into the container’s /conf directory.

Create a conf directory and neo4.conf file in $HOME/neo4j

mkdir $HOME/neo4j/conf && \
touch $HOME/neo4j/conf/neo4j.conf

Insert the following configuration into neo4j.conf making sure to substitute with the required DNS name for the server/ application.

# Bolt SSL configuration

# Https SSL configuration

The above will be mounted at deployment using --volume=$HOME/neo4j/conf:/conf

Docker Environment Variables

The following collection of Docker environment variables can be used instead of the above Docker host volume configuration. These should be specified at deployment making sure to substitute with the required DNS name for the server/ application.

--env \
--env NEO4J_dbms_ssl_policy_bolt_enabled=true \
--env NEO4J_dbms_ssl_policy_bolt_base__directory=certificates/bolt \
--env NEO4J_dbms_ssl_policy_bolt_private__key=private.key \
--env NEO4J_dbms_ssl_policy_bolt_public__certificate=public.crt \
--env NEO4J_dbms_ssl_policy_bolt_client__auth=NONE \
--env NEO4J_dbms_connector_bolt_tls__level=REQUIRED \
--env NEO4J_dbms_connector_https_enabled=true \
--env NEO4J_dbms_ssl_policy_https_enabled=true \
--env NEO4J_dbms_ssl_policy_https_base__directory=certificates/https \
--env NEO4J_dbms_ssl_policy_https_private__key=private.key \
--env NEO4J_dbms_ssl_policy_https_public__certificate=public.crt \
--env NEO4J_dbms_ssl_policy_https_client__auth=NONE \

4. Run Neo4j

With a host volume for neo4j.conf, the following command will deploy Neo4j 4.3.2:

docker run --name=neo4j-4.3.2 \
--publish=7474:7474 --publish=7687:7687 --publish=7473:7473 \
--volume=$HOME/neo4j/ssl:/ssl \
--volume=$HOME/neo4j/conf:/conf \
--env NEO4J_dbms_memory_pagecache_size=512m \

Neo4j 3.5

Add Docker Volume for storing of Certs

The Neo4j Docker image exposes a /ssl volume for mounting a directory on the host machine for storage of the certs:


In the above example, a local folder ($HOME/neo4j/ssl) will be used to store the cert and key.

Setup Configuration Settings within Neo4j to use above /ssl Volume

The Neo4j Docker container allows for use of a /conf volumn so that you are able to setup configuration settings in a Neo4j.conf file:


Using the above setting, we can modify the settings in a the Neo4j.conf file and place that file in the $HOME/neo4j/conf folder.

Alternatively, Environment variables can be used to set the configuration settings, as outlined here:

To configure secure Bolt and HTTPs communication, the following configuration parameters are required:

  • bolt.ssl_policy=client_policy

  • https.ssl_policy=client_policy

  • dbms.ssl.policy.client_policy.base_directory=/ssl/client_policy

  • dbms.ssl.policy.client_policy.client_auth=NONE

A key note here is that base_directory setting starts with /ssl - this will be mapped to the mounted drive and look for client_policy directory in the $HOME/neo4j/ssl folder.

Copy Cert/Key to Host Folders

With the above settings, the following folder structure and files on the host will be required:


If the key/crt files are named something other then the default, the following settings will be required:


Sample Docker Run Command

The following is a sample Command to start the Docker container with the above settings:

$ docker run --publish=7473:7473 --publish=7687:7687 --volume=$HOME/neo4j/ssl:/ssl  --volume=$HOME/neo4j/conf:/conf --env=NEO4J_ACCEPT_LICENSE_AGREEMENT=yes neo4j:3.4-enterprise