Gerrit Master-Slave

This set of Templates provide all the components to deploy a single Gerrit master and a single Gerrit slave in ECS


Five templates are provided in this example:

  • cf-cluster: define the ECS cluster and the networking stack
  • cf-service-master: define the service stack running Gerrit master
  • cf-service-slave: define the service stack running Gerrit slave
  • cf-dns-route: define the DNS routing for the service
  • cf-dashboard: define the CloudWatch dashboard for the services


  • Single VPC:
  • CIDR:
  • Single Availability Zone
  • 1 public Subnets:
  • CIDR:
  • 1 public NLB exposing:
  • Gerrit master HTTP on port 8080
  • Gerrit master SSH on port 29418
  • 1 public NLB exposing:
  • Gerrit slave HTTP on port 8081
  • Gerrit slave SSH on port 39418
  • SSH agent on port 1022
  • Git daemon on port 9418
  • 1 Internet Gateway
  • 2 type A alias DNS entry, for Gerrit master and slave
  • A SSL certificate available in AWS Certificate Manager

Data persistency

  • EBS volumes for:
    • Indexes
    • Caches
    • Data
    • Git repositories

Deployment type

  • Latest Gerrit version deployed using the official Docker image
  • Application deployed in ECS on a single EC2 instance


  • Gerrit error_log is exported in a Log Group in CloudWatch
  • Other Gerrit logs still need to be exported


  • Standard CloudWatch monitoring metrics for each component
  • Application level CloudWatch monitoring can be enabled as described here
  • Optionally Prometheus and Grafana stack (see here)

How to run it

0 - Prerequisites

Follow the steps described in the Prerequisites section

1 - Configuration

Please refer to the configuration docs to understand how to set up the configuration and what common configuration values are needed. On top of that, you might set the additional parameters, specific for this recipe.


Configuration values affecting deployment environment and cluster properties

  • SERVICE_MASTER_STACK_NAME: Optional. Name of the master service stack. gerrit-service-master by default.
  • SERVICE_SLAVE_STACK_NAME: Optional. Name of the slave service stack. gerrit-service-slave by default.
  • DASHBOARD_STACK_NAME : Optional. Name of the dashboard stack. gerrit-dashboard by default.
  • MASTER_SUBDOMAIN: Optional. Name of the master sub domain. gerrit-master-demo by default.
  • SLAVE_SUBDOMAIN: Optional. Name of the slave sub domain. gerrit-slave-demo by default.
  • CLUSTER_DESIRED_CAPACITY: Optional. Number of EC2 instances composing the cluster. 1 by default.
  • GERRIT_MASTER_INSTANCE_ID: Optional. Identifier for the Gerrit master instance. “gerrit-master-slave-MASTER” by default.
  • GERRIT_SLAVE_INSTANCE_ID: Optional. Identifier for the Gerrit slave instance. “gerrit-master-slave-SLAVE” by default.

NOTE: if you are planning to run the monitoring stack, set the CLUSTER_DESIRED_CAPACITY value to at least 2. The resources provided by a single EC2 instance won't be enough for all the services that will be ran*

  • PROMETHEUS_SUBDOMAIN: Optional. Prometheus subdomain. For example: <AWS_PREFIX>-prometheus
  • GRAFANA_SUBDOMAIN: Optional. Grafana subdomain. For example: <AWS_PREFIX>-grafana

2 - Deploy

  • Create the cluster, services and DNS routing stacks:
make [AWS_REGION=a-valid-aws-region] [AWS_PREFIX=some-cluster-prefix] create-all

The optional AWS_REGION and AWS_REFIX allow you to define where it will be deployed and what it will be named.

It might take several minutes to build the stack. You can monitor the creations of the stacks in CloudFormation

  • NOTE: the creation of the cluster needs an EC2 key pair are useful when you need to connect to the EC2 instances for troubleshooting purposes. The key pair is automatically generated and stored in a pem file on the current directory. To use when ssh-ing into your instances as follow: ssh -i cluster-keys.pem ec2-user@<ec2_instance_ip>

Cleaning up

make [AWS_REGION=a-valid-aws-region] [AWS_PREFIX=some-cluster-prefix] delete-all

The optional AWS_REGION and AWS_REFIX allow you to specify exactly which stack you target for deletion.

Note that this will not delete:

  • Secrets stored in Secret Manager
  • SSL certificates
  • ECR repositories

Access your Gerrit instances

Get the URL of your Gerrit master instance this way:

aws cloudformation describe-stacks \
  --stack-name <SERVICE_MASTER_STACK_NAME> \
  | grep -A1 '"OutputKey": "CanonicalWebUrl"' \
  | grep OutputValue \
  | cut -d'"' -f 4

Similarly for the slave:

aws cloudformation describe-stacks \
  --stack-name <SERVICE_SLAVE_STACK_NAME> \
  | grep -A1 '"OutputKey": "CanonicalWebUrl"' \
  | grep OutputValue \
  | cut -d'"' -f 4

Gerrit master instance ports:

  • HTTP 8080
  • SSH 29418

Gerrit slave instance ports:

  • HTTP 9080
  • SSH 39418


Refer to the Docker section for information on how to setup docker or how to publish images