gitlab-org--gitlab-foss/doc/install/aws/index.md

---
type: howto
---

# Installing GitLab HA on Amazon Web Services (AWS)

DANGER: **Danger:** This guide is under review and the steps below will be revised and updated in due time. For more detail, please see [this epic](https://gitlab.com/groups/gitlab-org/-/epics/912).

This page offers a walkthrough of a common HA (Highly Available) configuration
for GitLab on AWS. You should customize it to accommodate your needs.

NOTE: **Note**
For organizations with 300 users or less, the recommended AWS installation method is to launch an EC2 single box [Omnibus Installation](https://about.gitlab.com/install/) and implement a snapshot strategy for backing up the data.

## Introduction

GitLab on AWS can leverage many of the services that are already
configurable with GitLab High Availability (HA). These services offer a great deal of
flexibility and can be adapted to the needs of most companies, while enabling the
automation of both vertical and horizontal scaling.

In this guide, we'll go through a basic HA setup where we'll start by
configuring our Virtual Private Cloud and subnets to later integrate
services such as RDS for our database server and ElastiCache as a Redis
cluster to finally manage them within an auto scaling group with custom
scaling policies.

## Requirements

In addition to having a basic familiarity with [AWS](https://docs.aws.amazon.com/) and [Amazon EC2](https://docs.aws.amazon.com/ec2/), you will need:

- [An AWS account](https://console.aws.amazon.com/console/home)
- [To create or upload an SSH key](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-key-pairs.html)
  to connect to the instance via SSH
- A domain name for the GitLab instance
- An SSL/TLS certificate to secure your domain. If you do not already own one, you can provision a free public SSL/TLS certificate through [AWS Certificate Manager](https://aws.amazon.com/certificate-manager/)(ACM) for use with the [Elastic Load Balancer](#load-balancer) we'll create.

NOTE: **Note:** It can take a few hours to validate a certificate provisioned through ACM. To avoid delays later, request your certificate as soon as possible.

## Architecture

Below is a diagram of the recommended architecture.

![AWS architecture diagram](img/aws_ha_architecture_diagram.png)

## AWS costs

Here's a list of the AWS services we will use, with links to pricing information:

- **EC2**: GitLab will deployed on shared hardware which means
  [on-demand pricing](https://aws.amazon.com/ec2/pricing/on-demand/)
  will apply. If you want to run it on a dedicated or reserved instance,
  consult the [EC2 pricing page](https://aws.amazon.com/ec2/pricing/) for more
  information on the cost.
- **S3**: We will use S3 to store backups, artifacts, LFS objects, etc. See the
  [Amazon S3 pricing](https://aws.amazon.com/s3/pricing/).
- **ELB**: A Classic Load Balancer will be used to route requests to the
  GitLab instances. See the [Amazon ELB pricing](https://aws.amazon.com/elasticloadbalancing/pricing/).
- **RDS**: An Amazon Relational Database Service using PostgreSQL will be used
  to provide a High Availability database configuration. See the
  [Amazon RDS pricing](https://aws.amazon.com/rds/postgresql/pricing/).
- **ElastiCache**: An in-memory cache environment will be used to provide a
  High Availability Redis configuration. See the
  [Amazon ElastiCache pricing](https://aws.amazon.com/elasticache/pricing/).

NOTE: **Note:** Please note that while we will be using EBS for storage, we do not recommend using EFS as it may negatively impact GitLab's performance. You can review the [relevant documentation](../../administration/high_availability/nfs.md#avoid-using-awss-elastic-file-system-efs) for more details.

## Creating an IAM EC2 instance role and profile

To minimize the permissions of the user, we'll create a new [IAM](https://docs.aws.amazon.com/IAM/latest/UserGuide/introduction.html)
role with limited access:

1. Navigate to the IAM dashboard <https://console.aws.amazon.com/iam/home> and
   click **Create role**.
1. Create a new role by selecting **AWS service > EC2**, then click
   **Next: Permissions**.
1. Choose **AmazonEC2FullAccess** and **AmazonS3FullAccess**, then click **Next: Review**.
1. Give the role the name `GitLabAdmin` and click **Create role**.

## Configuring the network

We'll start by creating a VPC for our GitLab cloud infrastructure, then
we can create subnets to have public and private instances in at least
two [Availability Zones (AZs)](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-regions-availability-zones.html). Public subnets will require a Route Table keep and an associated
Internet Gateway.

### Creating the Virtual Private Cloud (VPC)

We'll now create a VPC, a virtual networking environment that you'll control:

1. Navigate to <https://console.aws.amazon.com/vpc/home>.
1. Select **Your VPCs** from the left menu and then click **Create VPC**.
   At the "Name tag" enter `gitlab-vpc` and at the "IPv4 CIDR block" enter
   `10.0.0.0/16`. If you don't require dedicated hardware, you can leave
   "Tenancy" as default. Click **Yes, Create** when ready.

   ![Create VPC](img/create_vpc.png)

### Subnets

Now, let's create some subnets in different Availability Zones. Make sure
that each subnet is associated to the VPC we just created and
that CIDR blocks don't overlap. This will also
allow us to enable multi AZ for redundancy.

We will create private and public subnets to match load balancers and
RDS instances as well:

1. Select **Subnets** from the left menu.
1. Click **Create subnet**. Give it a descriptive name tag based on the IP,
   for example `gitlab-public-10.0.0.0`, select the VPC we created previously,
   and at the IPv4 CIDR block let's give it a 24 subnet `10.0.0.0/24`:

   ![Create subnet](img/create_subnet.png)

1. Follow the same steps to create all subnets:

   | Name tag                  | Type    | Availability Zone | CIDR block    |
   | ------------------------- | ------- | ----------------- | ------------- |
   | `gitlab-public-10.0.0.0`  | public  | `us-west-2a`      | `10.0.0.0/24` |
   | `gitlab-private-10.0.1.0` | private | `us-west-2a`      | `10.0.1.0/24` |
   | `gitlab-public-10.0.2.0`  | public  | `us-west-2b`      | `10.0.2.0/24` |
   | `gitlab-private-10.0.3.0` | private | `us-west-2b`      | `10.0.3.0/24` |

### Create NAT Gateways

Instances deployed in our private subnets need to connect to the internet for updates, but should not be reachable from the public internet. To achieve this, we'll make use of [NAT Gateways](https://docs.aws.amazon.com/vpc/latest/userguide/vpc-nat-gateway.html) deployed in each of our public subnets:

1. Navigate to the VPC dashboard and click on **NAT Gateways** in the left menu bar.
1. Click **Create NAT Gateway** and complete the following:
   1. **Subnet**: Select `gitlab-public-10.0.0.0` from the dropdown.
   1. **Elastic IP Allocation ID**: Enter an existing Elastic IP or click **Allocate Elastic IP address** to allocate a new IP to your NAT gateway.
   1. Add tags if needed.
   1. Click **Create NAT Gateway**.

Create a second NAT gateway but this time place it in the second public subnet, `gitlab-public-10.0.2.0`.

### Internet Gateway

Now, still on the same dashboard, go to Internet Gateways and
create a new one:

1. Select **Internet Gateways** from the left menu.
1. Click **Create internet gateway**, give it the name `gitlab-gateway` and
   click **Create**.
1. Select it from the table, and then under the **Actions** dropdown choose
   "Attach to VPC".

   ![Create gateway](img/create_gateway.png)

1. Choose `gitlab-vpc` from the list and hit **Attach**.

### Route Tables

#### Public Route Table

We need to create a route table for our public subnets to reach the internet via the internet gateway we created in the previous step.

On the VPC dashboard:

1. Select **Route Tables** from the left menu.
1. Click **Create Route Table**.
1. At the "Name tag" enter `gitlab-public` and choose `gitlab-vpc` under "VPC".
1. Click **Create**.

We now need to add our internet gateway as a new target and have
it receive traffic from any destination.

1. Select **Route Tables** from the left menu and select the `gitlab-public`
   route to show the options at the bottom.
1. Select the **Routes** tab, click **Edit routes > Add route** and set `0.0.0.0/0`
   as the destination. In the target column, select the `gitlab-gateway` we created previously.
   Hit **Save routes** once done.

Next, we must associate the **public** subnets to the route table:

1. Select the **Subnet Associations** tab and click **Edit subnet associations**.
1. Check only the public subnets and click **Save**.

#### Private Route Tables

We also need to create two private route tables so that instances in each private subnet can reach the internet via the NAT gateway in the corresponding public subnet in the same availability zone.

1. Follow the same steps as above to create two private route tables. Name them `gitlab-public-a` and `gitlab-public-b` respectively.
1. Next, add a new route to each of the private route tables where the destination is `0.0.0.0/0` and the target is one of the NAT gateways we created earlier.
   1. Add the NAT gateway we created in `gitlab-public-10.0.0.0` as the target for the new route in the `gitlab-public-a` route table.
   1. Similarly, add the NAT gateway in `gitlab-public-10.0.2.0` as the target for the new route in the `gitlab-public-b`.
1. Lastly, associate each private subnet with a private route table.
   1. Associate `gitlab-private-10.0.1.0` with `gitlab-public-a`.
   1. Associate `gitlab-private-10.0.3.0` with `gitlab-public-b`.

## Load Balancer

On the EC2 dashboard, look for Load Balancer in the left navigation bar:

1. Click the **Create Load Balancer** button.
   1. Choose the **Classic Load Balancer**.
   1. Give it a name (we'll use `gitlab-loadbalancer`) and for the **Create LB Inside** option, select `gitlab-vpc` from the dropdown menu.
   1. In the **Listeners** section, set HTTP port 80, HTTPS port 443, and TCP port 22 for both load balancer and instance protocols and ports.
   1. In the **Select Subnets** section, select both public subnets from the list.
1. Click **Assign Security Groups** and select **Create a new security group**, give it a name
   (we'll use `gitlab-loadbalancer-sec-group`) and description, and allow both HTTP and HTTPS traffic
   from anywhere (`0.0.0.0/0, ::/0`).
1. Click **Configure Security Settings** and select an SSL/TLS certificate from ACM or upload a certificate to IAM.
1. Click **Configure Health Check** and set up a health check for your EC2 instances.
   1. For **Ping Protocol**, select HTTP.
   1. For **Ping Port**, enter 80.
   1. For **Ping Path**, enter `/explore`. (We use `/explore` as it's a public endpoint that does
   not require authorization.)
   1. Keep the default **Advanced Details** or adjust them according to your needs.
1. Click **Add EC2 Instances** but, as we don't have any instances to add yet, come back
to your load balancer after creating your GitLab instances and add them.
1. Click **Add Tags** and add any tags you need.
1. Click **Review and Create**, review all your settings, and click **Create** if you're happy.

After the Load Balancer is up and running, you can revisit your Security
Groups to refine the access only through the ELB and any other requirements
you might have.

### Configure DNS for Load Balancer

On the Route 53 dashboard, click **Hosted zones** in the left navigation bar:

1. Select an existing hosted zone or, if you do not already have one for your domain, click **Create Hosted Zone**, enter your domain name, and click **Create**.
1. Click **Create Record Set** and provide the following values:
    1. **Name:** Use the domain name (the default value) or enter a subdomain.
    1. **Type:** Select **A - IPv4 address**.
    1. **Alias Target:** Find the **ELB Classic Load Balancers** section and select the classic load balancer we created earlier.
    1. **Routing Policy:** We'll use **Simple** but you can choose a different policy based on your use case.
    1. **Evaluate Target Health:** We'll set this to **No** but you can choose to have the load balancer route traffic based on target health.
    1. Click **Create**.
1. Update your DNS records with your domain registrar. The steps for doing this vary depending on which registrar you use and is beyond the scope of this guide.

## PostgreSQL with RDS

For our database server we will use Amazon RDS which offers Multi AZ
for redundancy. Let's start by creating a subnet group and then we'll
create the actual RDS instance.

### RDS Subnet Group

1. Navigate to the RDS dashboard and select **Subnet Groups** from the left menu.
1. Click on **Create DB Subnet Group**.
1. Under **Subnet group details**, enter a name (we'll use `gitlab-rds-group`), a description, and choose the `gitlab-vpc` from the VPC dropdown.
1. Under **Add subnets**, click **Add all the subnets related to this VPC** and remove the public ones, we only want the **private subnets**. In the end, you should see `10.0.1.0/24` and `10.0.3.0/24` (as we defined them in the [subnets section](#subnets)).
1. Click **Create** when ready.

   ![RDS Subnet Group](img/rds_subnet_group.png)

### RDS Security Group

We need a security group for our database that will allow inbound traffic from the instances we'll deploy in our `gitlab-loadbalancer-sec-group` later on:

1. From the EC2 dashboard, select **Security Groups** from the left menu bar.
1. Click **Create security group**.
1. Give it a name (we'll use `gitlab-rds-sec-group`), a description, and select the `gitlab-vpc` from the **VPC** dropdown.
1. In the **Inbound rules** section, click **Add rule** and add a **PostgreSQL** rule, and set the "Custom" source as the `gitlab-loadbalancer-sec-group` we created earlier. The default PostgreSQL port is `5432`, which we'll also use when creating our database below.
1. When done, click **Create security group**.

### Create the database

Now, it's time to create the database:

1. Select **Databases** from the left menu and click **Create database**.
1. Select **Standard Create** for the database creation method.
1. Select **PostgreSQL** as the database engine and select **PostgreSQL 10.9-R1** from the version dropdown menu (check the [database requirements](../../install/requirements.md#postgresql-requirements) to see if there are any updates on this for your chosen version of GitLab).
1. Since this is a production server, let's choose **Production** from the **Templates** section.
1. Under **Settings**, set a DB instance identifier, a master username, and a master password. We'll use `gitlab-db-ha`, `gitlab`, and a very secure password respectively. Make a note of these as we'll need them later.
1. For the DB instance size, select **Standard classes** and select an instance size that meets your requirements from the dropdown menu. We'll use a `db.m4.large` instance.
1. Under **Storage**, configure the following:
   1. Select **Provisioned IOPS (SSD)** from the storage type dropdown menu. Provisioned IOPS (SSD) storage is best suited for HA (though you can choose General Purpose (SSD) to reduce the costs). Read more about it at [Storage for Amazon RDS](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_Storage.html).
   1. Allocate storage and set provisioned IOPS. We'll use the minimum values, `100` and `1000`, respectively.
   1. Enable storage autoscaling (optional) and set a maximum storage threshold.
1. Under **Availability & durability**, select **Create a standby instance** to have a standby RDS instance provisioned in a different Availability Zone. Read more at [High Availability (Multi-AZ)](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Concepts.MultiAZ.html).
1. Under **Connectivity**, configure the following:
   1. Select the VPC we created earlier (`gitlab-vpc`) from the **Virtual Private Cloud (VPC)** dropdown menu.
   1. Expand the **Additional connectivity configuration** section and select the subnet group (`gitlab-rds-group`) we created earlier.
   1. Set public accessibility to **No**.
   1. Under **VPC security group**, select **Choose existing** and select the `gitlab-rds-sec-group` we create above from the dropdown.
   1. Leave the database port as the default `5432`.
1. For **Database authentication**, select **Password authentication**.
1. Expand the **Additional configuration** section and complete the following:
   1. The initial database name. We'll use `gitlabhq_production`.
   1. Configure your preferred backup settings.
   1. The only other change we'll make here is to disable auto minor version updates under **Maintenance**.
   1. Leave all the other settings as is or tweak according to your needs.
   1. Once you're happy, click **Create database**.

Now that the database is created, let's move on to setting up Redis with ElastiCache.

## Redis with ElastiCache

ElastiCache is an in-memory hosted caching solution. Redis maintains its own
persistence and is used for certain types of the GitLab application.

### Redis Subnet Group

1. Navigate to the ElastiCache dashboard from your AWS console.
1. Go to **Subnet Groups** in the left menu, and create a new subnet group.
   Make sure to select our VPC and its [private subnets](#subnets). Click
   **Create** when ready.

   ![ElastiCache subnet](img/ec_subnet.png)

### Create a Redis Security Group

1. Navigate to the EC2 dashboard.
1. Select **Security Groups** from the left menu.
1. Click **Create security group** and fill in the details. Give it a name (we'll use `gitlab-redis-sec-group`),
   add a description, and choose the VPC we created previously
1. In the **Inbound rules** section, click **Add rule** and add a **Custom TCP** rule, set port `6379`, and set the "Custom" source as the `gitlab-loadbalancer-sec-group` we created earlier.
1. When done, click **Create security group**.

### Create the Redis Cluster

1. Navigate back to the ElastiCache dashboard.
1. Select **Redis** on the left menu and click **Create** to create a new
   Redis cluster. Do not enable **Cluster Mode** as it is [not supported](../../administration/high_availability/redis.md#provide-your-own-redis-instance-core-only). Even without cluster mode on, you still get the
   chance to deploy Redis in multiple availability zones.
1. In the settings section:
   1. Give the cluster a name (`gitlab-redis`) and a description.
   1. For the version, select the latest of `5.0` series (e.g., `5.0.6`).
   1. Leave the port as `6379` since this is what we used in our Redis security group above.
   1. Select the node type (at least `cache.t3.medium`, but adjust to your needs) and the number of replicas.
1. In the advanced settings section:
   1. Select the multi-AZ auto-failover option.
   1. Select the subnet group we created previously.
   1. Manually select the preferred availability zones, and under "Replica 2"
      choose a different zone than the other two.

      ![Redis availability zones](img/ec_az.png)

1. In the security settings, edit the security groups and choose the
   `gitlab-redis-sec-group` we had previously created.
1. Leave the rest of the settings to their default values or edit to your liking.
1. When done, click **Create**.

## Setting up Bastion Hosts

Since our GitLab instances will be in private subnets, we need a way to connect to these instances via SSH to make configuration changes, perform upgrades, etc. One way of doing this is via a [bastion host](https://en.wikipedia.org/wiki/Bastion_host), sometimes also referred to as a jump box.

TIP: **Tip:** If you do not want to maintain bastion hosts, you can set up [AWS Systems Manager Session Manager](https://docs.aws.amazon.com/systems-manager/latest/userguide/session-manager.html) for access to instances. This is beyond the scope of this document.

### Create Bastion Host A

1. Navigate to the EC2 Dashboard and click on **Launch instance**.
1. Select the **Ubuntu Server 18.04 LTS (HVM)** AMI.
1. Choose an instance type. We'll use a `t2.micro` as we'll only use the bastion host to SSH into our other instances.
1. Click **Configure Instance Details**.
   1. Under **Network**, select the `gitlab-vpc` from the dropdown menu.
   1. Under **Subnet**, select the public subnet we created earlier (`gitlab-public-10.0.0.0`).
   1. Double check that under **Auto-assign Public IP** you have **Use subnet setting (Enable)** selected.
   1. Leave everything else as default and click **Add Storage**.
1. For storage, we'll leave everything as default and only add an 8GB root volume. We won't store anything on this instance.
1. Click **Add Tags** and on the next screen click **Add Tag**.
   1. We’ll only set `Key: Name` and `Value: Bastion Host A`.
1. Click **Configure Security Group**.
   1. Select **Create a new security group**, enter a **Security group name** (we'll use `bastion-sec-group`), and add a description.
   1. We'll enable SSH access from anywhere (`0.0.0.0/0`). If you want stricter security, specify a single IP address or an IP address range in CIDR notation.
   1. Click **Review and Launch**
1. Review all your settings and, if you're happy, click **Launch**.
1. Acknowledge that you have access to an existing key pair or create a new one. Click **Launch Instance**.

Confirm that you can SSH into the instance:

1. On the EC2 Dashboard, click on **Instances** in the left menu.
1. Select **Bastion Host A** from your list of instances.
1. Click **Connect** and follow the connection instructions.
1. If you are able to connect successfully, let's move on to setting up our second bastion host for redundancy.

### Create Bastion Host B

1. Create an EC2 instance following the same steps as above with the following changes:
   1. For the **Subnet**, select the second public subnet we created earlier (`gitlab-public-10.0.2.0`).
   1. Under the **Add Tags** section, we’ll set `Key: Name` and `Value: Bastion Host B` so that we can easily identify our two instances.
   1. For the security group, select the existing `bastion-sec-group` we created above.

### Use SSH Agent Forwarding

EC2 instances running Linux use private key files for SSH authentication. You'll connect to your bastion host using an SSH client and the private key file stored on your client. Since the private key file is not present on the bastion host, you will not be able to connect to your instances in private subnets.

Storing private key files on your bastion host is a bad idea. To get around this, use SSH agent forwarding on your client. See [Securely Connect to Linux Instances Running in a Private Amazon VPC](https://aws.amazon.com/blogs/security/securely-connect-to-linux-instances-running-in-a-private-amazon-vpc/) for a step-by-step guide on how to use SSH agent forwarding.

## Install GitLab and create custom AMI

We will need a preconfigured, custom GitLab AMI to use in our launch configuration later. As a starting point, we will use the official GitLab AMI to create a GitLab instance. Then, we'll add our custom configuration for PostgreSQL, Redis, and Gitaly. If you prefer, instead of using the official GitLab AMI, you can also spin up an EC2 instance of your choosing and [manually install GitLab](https://about.gitlab.com/install/).

### Install GitLab

From the EC2 dashboard:

1. Click **Launch Instance** and select **Community AMIs** from the left menu.
1. In the search bar, search for `GitLab EE <version>` where `<version>` is the latest version as seen on the [releases page](https://about.gitlab.com/releases/). Select the latest patch release, for example `GitLab EE 12.9.2`.
1. Select an instance type based on your workload. Consult the [hardware requirements](../../install/requirements.md#hardware-requirements) to choose one that fits your needs (at least `c5.xlarge`, which is sufficient to accommodate 100 users).
1. Click **Configure Instance Details**:
   1. In the **Network** dropdown, select `gitlab-vpc`, the VPC we created earlier.
   1. In the **Subnet** dropdown, `select gitlab-private-10.0.1.0` from the list of subnets we created earlier.
   1. Double check that **Auto-assign Public IP** is set to `Use subnet setting (Disable)`.
   1. Click **Add Storage**.
   1. The root volume is 8GiB by default and should be enough given that we won’t store any data there.
1. Click **Add Tags** and add any tags you may need. In our case, we'll only set `Key: Name` and `Value: GitLab`.
1. Click **Configure Security Group**. Check **Select an existing security group** and select the `gitlab-loadbalancer-sec-group` we created earlier.
1. Click **Review and launch** followed by **Launch** if you’re happy with your settings.
1. Finally, acknowledge that you have access to the selected private key file or create a new one. Click **Launch Instances**.

### Add custom configuration

Connect to your GitLab instance via **Bastion Host A** using [SSH Agent Forwarding](#use-ssh-agent-forwarding). Once connected, add the following custom configuration:

#### Install the `pg_trgm` extension for PostgreSQL

From your GitLab instance, connect to the RDS instance to verify access and to install the required `pg_trgm` extension.

To find the host or endpoint, navigate to **Amazon RDS > Databases** and click on the database you created earlier. Look for the endpoint under the **Connectivity & security** tab.

Do not to include the colon and port number:

```shell
sudo /opt/gitlab/embedded/bin/psql -U gitlab -h <rds-endpoint> -d gitlabhq_production
```

At the `psql` prompt create the extension and then quit the session:

```shell
psql (10.9)
Type "help" for help.

gitlab=# CREATE EXTENSION pg_trgm;
gitlab=# \q
```

#### Configure GitLab to connect to PostgreSQL and Redis

1. Edit `/etc/gitlab/gitlab.rb`, find the `external_url 'http://<domain>'` option
   and change it to the `https` domain you will be using.

1. Look for the GitLab database settings and uncomment as necessary. In
   our current case we'll specify the database adapter, encoding, host, name,
   username, and password:

   ```ruby
   # Disable the built-in Postgres
    postgresql['enable'] = false

   # Fill in the connection details
   gitlab_rails['db_adapter'] = "postgresql"
   gitlab_rails['db_encoding'] = "unicode"
   gitlab_rails['db_database'] = "gitlabhq_production"
   gitlab_rails['db_username'] = "gitlab"
   gitlab_rails['db_password'] = "mypassword"
   gitlab_rails['db_host'] = "<rds-endpoint>"
   ```

1. Next, we need to configure the Redis section by adding the host and
   uncommenting the port:

   ```ruby
   # Disable the built-in Redis
   redis['enable'] = false

   # Fill in the connection details
   gitlab_rails['redis_host'] = "<redis-endpoint>"
   gitlab_rails['redis_port'] = 6379
   ```

1. Finally, reconfigure GitLab for the changes to take effect:

   ```shell
   sudo gitlab-ctl reconfigure
   ```

1. You might also find it useful to run a check and a service status to make sure
   everything has been setup correctly:

   ```shell
   sudo gitlab-rake gitlab:check
   sudo gitlab-ctl status
   ```

#### Set up Gitaly

CAUTION: **Caution:** In this architecture, having a single Gitaly server creates a single point of failure. This limitation will be removed once [Gitaly HA](https://gitlab.com/groups/gitlab-org/-/epics/842) is released.

Gitaly is a service that provides high-level RPC access to Git repositories.
It should be enabled and configured on a separate EC2 instance in one of the
[private subnets](#subnets) we configured previously.

Let's create an EC2 instance where we'll install Gitaly:

1. From the EC2 dashboard, click **Launch instance**.
1. Choose an AMI. In this example, we'll select the **Ubuntu Server 18.04 LTS (HVM), SSD Volume Type**.
1. Choose an instance type. We'll pick a **c5.xlarge**.
1. Click **Configure Instance Details**.
   1. In the **Network** dropdown, select `gitlab-vpc`, the VPC we created earlier.
   1. In the **Subnet** dropdown, select `gitlab-private-10.0.1.0` from the list of subnets we created earlier.
   1. Double check that **Auto-assign Public IP** is set to `Use subnet setting (Disable)`.
   1. Click **Add Storage**.
1. Increase the Root volume size to `20 GiB` and change the **Volume Type** to `Provisoned IOPS SSD (io1)`. (This is an arbitrary size. Create a volume big enough for your repository storage requirements.)
   1. For **IOPS** set `1000` (20 GiB x 50 IOPS). You can provision up to 50 IOPS per GiB. If you select a larger volume, increase the IOPS accordingly. Workloads where many small files are written in a serialized manner, like `git`, requires performant storage, hence the choice of `Provisoned IOPS SSD (io1)`.
1. Click on **Add Tags** and add your tags. In our case, we'll only set `Key: Name` and `Value: Gitaly`.
1. Click on **Configure Security Group** and let's **Create a new security group**.
   1. Give your security group a name and description. We'll use `gitlab-gitaly-sec-group` for both.
   1. Create a **Custom TCP** rule and add port `8075` to the **Port Range**. For the **Source**, select the `gitlab-loadbalancer-sec-group`.
1. Click **Review and launch** followed by **Launch** if you're happy with your settings.
1. Finally, acknowledge that you have access to the selected private key file or create a new one. Click **Launch Instances**.

  > **Optional:** Instead of storing configuration _and_ repository data on the root volume, you can also choose to add an additional EBS volume for repository storage. Follow the same guidance as above. See the [Amazon EBS pricing](https://aws.amazon.com/ebs/pricing/).

Now that we have our EC2 instance ready, follow the [documentation to install GitLab and set up Gitaly on its own server](../../administration/gitaly/index.md#running-gitaly-on-its-own-server). Perform the client setup steps from that document on the [GitLab instance we created](#install-gitlab) above.

#### Add Support for Proxied SSL

As we are terminating SSL at our [load balancer](#load-balancer), follow the steps at [Supporting proxied SSL](https://docs.gitlab.com/omnibus/settings/nginx.html#supporting-proxied-ssl) to configure this in `/etc/gitlab/gitlab.rb`.

Remember to run `sudo gitlab-ctl reconfigure` after saving the changes to the `gitlab.rb` file.

#### Disable Let's Encrypt

Since we're adding our SSL certificate at the load balancer, we do not need GitLab's built-in support for Let's Encrypt. Let's Encrypt [is enabled by default](https://docs.gitlab.com/omnibus/settings/ssl.html#lets-encrypt-integration) when using an `https` domain since GitLab 10.7, so we need to explicitly disable it:

1. Open `/etc/gitlab/gitlab.rb` and disable it:

   ```ruby
   letsencrypt['enable'] = false
   ```

1. Save the file and reconfigure for the changes to take effect:

   ```shell
   sudo gitlab-ctl reconfigure
   ```

#### Configure host keys

Ordinarily we would manually copy the contents (primary and public keys) of `/etc/ssh/` on the primary application server to `/etc/ssh` on all secondary servers. This prevents false man-in-the-middle-attack alerts when accessing servers in your High Availability cluster behind a load balancer.

We'll automate this by creating static host keys as part of our custom AMI. As these host keys are also rotated every time an EC2 instance boots up, "hard coding" them into our custom AMI serves as a handy workaround.

On your GitLab instance run the following:

```shell
mkdir /etc/ssh_static
cp -R /etc/ssh/* /etc/ssh_static
```

In `/etc/ssh/sshd_config` update the following:

```bash
  # HostKeys for protocol version 2
  HostKey /etc/ssh_static/ssh_host_rsa_key
  HostKey /etc/ssh_static/ssh_host_dsa_key
  HostKey /etc/ssh_static/ssh_host_ecdsa_key
  HosstKey /etc/ssh_static/ssh_host_ed25519_key
```

#### Amazon S3 object storage

Since we're not using NFS for shared storage, we will use [Amazon S3](https://aws.amazon.com/s3/) buckets to store backups, artifacts, LFS objects, uploads, merge request diffs, container registry images, and more. For instructions on how to configure each of these, please see [Cloud Object Storage](../../administration/high_availability/object_storage.md).

Remember to run `sudo gitlab-ctl reconfigure` after saving the changes to the `gitlab.rb` file.

NOTE: **Note:**
One current feature of GitLab that still requires a shared directory (NFS) is
[GitLab Pages](../../user/project/pages/index.md).
There is [work in progress](https://gitlab.com/gitlab-org/gitlab-pages/issues/196)
to eliminate the need for NFS to support GitLab Pages.

---

That concludes the configuration changes for our GitLab instance. Next, we'll create a custom AMI based on this instance to use for our launch configuration and auto scaling group.

### Create custom AMI

On the EC2 dashboard:

1. Select the `GitLab` instance we [created earlier](#install-gitLab).
1. Click on **Actions**, scroll down to **Image** and click **Create Image**.
1. Give your image a name and description (we'll use `GitLab-Source` for both).
1. Leave everything else as default and click **Create Image**

Now we have a custom AMI that we'll use to create our launch configuration the next step.

## Deploying GitLab inside an auto scaling group

We'll use AWS's wizard to deploy GitLab and then SSH into the instance to
configure the PostgreSQL and Redis connections.

The Auto Scaling Group option is available through the EC2 dashboard on the left
sidebar.

1. Click **Create Auto Scaling group**.
1. Create a new launch configuration.

### Choose the AMI

Choose the AMI:

1. Go to the Community AMIs and search for `GitLab EE <version>`
   where `<version>` the latest version as seen on the
   [releases page](https://about.gitlab.com/releases/).

   ![Choose AMI](img/choose_ami.png)

### Choose an instance type

You should choose an instance type based on your workload. Consult
[the hardware requirements](../requirements.md#hardware-requirements) to choose
one that fits your needs (at least `c5.xlarge`, which is enough to accommodate 100 users):

1. Choose the your instance type.
1. Click **Next: Configure Instance Details**.

### Configure details

In this step we'll configure some details:

1. Enter a name (`gitlab-autoscaling`).
1. Select the IAM role we created.
1. Optionally, enable CloudWatch and the EBS-optimized instance settings.
1. In the "Advanced Details" section, set the IP address type to
   "Do not assign a public IP address to any instances."
1. Click **Next: Add Storage**.

### Add storage

The root volume is 8GB by default and should be enough given that we won't store any data there.

### Configure security group

As a last step, configure the security group:

1. Select the existing load balancer security group we have [created](#load-balancer).
1. Select **Review**.

### Review and launch

Now is a good time to review all the previous settings. When ready, click
**Create launch configuration** and select the SSH key pair with which you will
connect to the instance.

### Create Auto Scaling Group

We are now able to start creating our Auto Scaling Group:

1. Give it a group name.
1. Set the group size to 2 as we want to always start with two instances.
1. Assign it our network VPC and add the **private subnets**.
1. In the "Advanced Details" section, choose to receive traffic from ELBs
   and select our ELB.
1. Choose the ELB health check.
1. Click **Next: Configure scaling policies**.

This is the really great part of Auto Scaling; we get to choose when AWS
launches new instances and when it removes them. For this group we'll
scale between 2 and 4 instances where one instance will be added if CPU
utilization is greater than 60% and one instance is removed if it falls
to less than 45%.

![Auto scaling group policies](img/policies.png)

Finally, configure notifications and tags as you see fit, and create the
auto scaling group.

You'll notice that after we save the configuration, AWS starts launching our two
instances in different AZs and without a public IP which is exactly what
we intended.

## Health check and monitoring with Prometheus

Apart from Amazon's Cloudwatch which you can enable on various services,
GitLab provides its own integrated monitoring solution based on Prometheus.
For more information on how to set it up, visit the
[GitLab Prometheus documentation](../../administration/monitoring/prometheus/index.md)

GitLab also has various [health check endpoints](../..//user/admin_area/monitoring/health_check.md)
that you can ping and get reports.

## GitLab Runners

If you want to take advantage of [GitLab CI/CD](../../ci/README.md), you have to
set up at least one [GitLab Runner](https://docs.gitlab.com/runner/).

Read more on configuring an
[autoscaling GitLab Runner on AWS](https://docs.gitlab.com/runner/configuration/runner_autoscale_aws/).

## Backup and restore

GitLab provides [a tool to backup](../../raketasks/backup_restore.md#creating-a-backup-of-the-gitlab-system)
and restore its Git data, database, attachments, LFS objects, etc.

Some important things to know:

- The backup/restore tool **does not** store some configuration files, like secrets; you'll
  need to [configure this yourself](../../raketasks/backup_restore.md#storing-configuration-files).
- By default, the backup files are stored locally, but you can
  [backup GitLab using S3](../../raketasks/backup_restore.md#using-amazon-s3).
- You can [exclude specific directories form the backup](../../raketasks/backup_restore.md#excluding-specific-directories-from-the-backup).

### Backing up GitLab

To back up GitLab:

1. SSH into your instance.
1. Take a backup:

   ```shell
   sudo gitlab-backup create
   ```

NOTE: **Note**
For GitLab 12.1 and earlier, use `gitlab-rake gitlab:backup:create`.

### Restoring GitLab from a backup

To restore GitLab, first review the [restore documentation](../../raketasks/backup_restore.md#restore),
and primarily the restore prerequisites. Then, follow the steps under the
[Omnibus installations section](../../raketasks/backup_restore.md#restore-for-omnibus-gitlab-installations).

## Updating GitLab

GitLab releases a new version every month on the 22nd. Whenever a new version is
released, you can update your GitLab instance:

1. SSH into your instance
1. Take a backup:

   ```shell
   sudo gitlab-backup create
   ```

NOTE: **Note**
For GitLab 12.1 and earlier, use `gitlab-rake gitlab:backup:create`.

1. Update the repositories and install GitLab:

   ```shell
   sudo apt update
   sudo apt install gitlab-ee
   ```

After a few minutes, the new version should be up and running.

## Conclusion

In this guide, we went mostly through scaling and some redundancy options,
your mileage may vary.

Keep in mind that all Highly Available solutions come with a trade-off between
cost/complexity and uptime. The more uptime you want, the more complex the solution.
And the more complex the solution, the more work is involved in setting up and
maintaining it.

Have a read through these other resources and feel free to
[open an issue](https://gitlab.com/gitlab-org/gitlab/issues/new)
to request additional material:

- [GitLab High Availability](../../administration/high_availability/README.md):
  GitLab supports several different types of clustering and high-availability.
- [Geo replication](../../administration/geo/replication/index.md):
  Geo is the solution for widely distributed development teams.
- [Omnibus GitLab](https://docs.gitlab.com/omnibus/) - Everything you need to know
  about administering your GitLab instance.
- [Upload a license](../../user/admin_area/license.md):
  Activate all GitLab Enterprise Edition functionality with a license.
- [Pricing](https://about.gitlab.com/pricing/): Pricing for the different tiers.

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