Gerrit Primary-Replica

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

Architecture

Five templates are provided in this example:

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

Networking

• Single VPC:
• CIDR: 10.0.0.0/16
• Single Availability Zone
• 1 public Subnets:
• CIDR: 10.0.0.0/24
• 1 public NLB exposing:
• Gerrit primary HTTP on port 8080
• Gerrit primary SSH on port 29418
• 1 public NLB exposing:
• Gerrit replica HTTP on port 8081
• Gerrit replica 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 primary and replica
• 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

Logging

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

Monitoring

• 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.

Environment

Configuration values affecting deployment environment and cluster properties

• SERVICE_PRIMARY_STACK_NAME: Optional. Name of the primary service stack. gerrit-service-primary by default.
• SERVICE_REPLICA_STACK_NAME: Optional. Name of the replica service stack. gerrit-service-replica by default.
• DASHBOARD_STACK_NAME : Optional. Name of the dashboard stack. gerrit-dashboard by default.
• PRIMARY_SUBDOMAIN: Optional. Name of the primary sub domain. gerrit-primary-demo by default.
• REPLICA_SUBDOMAIN: Optional. Name of the replica sub domain. gerrit-replica-demo by default.
• GERRIT_PRIMARY_INSTANCE_ID: Optional. Identifier for the Gerrit primary instance. “gerrit-primary-replica-PRIMARY” by default.
• GERRIT_REPLICA_INSTANCE_ID: Optional. Identifier for the Gerrit replica instance. “gerrit-primary-replica-REPLICA” by default.
• GERRIT_VOLUME_ID : Optional. Id of an extisting EBS volume. If empty, a new volume for Gerrit data will be created
• GERRIT_VOLUME_SNAPSHOT_ID : Optional. Ignored if GERRIT_VOLUME_ID is not empty. Id of the EBS volume snapshot used to create new EBS volume for Gerrit data.
• GERRIT_VOLUME_SIZE_IN_GIB: Optional. The size of the Gerrit data volume, in GiBs. 10 by default.

NOTE: if you are planning to run the monitoring stack, set the PRIMARY_MAX_COUNT 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 primary instance this way:

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

Similarly for the replica:

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

Gerrit primary instance ports:

• HTTP 8080
• SSH 29418

Gerrit replica instance ports:

• HTTP 9080
• SSH 39418

Docker

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