--- stage: Enablement group: Distribution info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments --- # Reference architecture: up to 2,000 users **(FREE SELF)** This page describes GitLab reference architecture for up to 2,000 users. For a full list of reference architectures, see [Available reference architectures](index.md#available-reference-architectures). > - **Supported users (approximate):** 2,000 > - **High Availability:** No. For a highly-available environment, you can > follow a modified [3K reference architecture](3k_users.md#supported-modifications-for-lower-user-counts-ha). > - **Estimated Costs:** [See cost table](index.md#cost-to-run) > - **Cloud Native Hybrid:** [Yes](#cloud-native-hybrid-reference-architecture-with-helm-charts-alternative) > - **Validation and test results:** The Quality Engineering team does [regular smoke and performance tests](index.md#validation-and-test-results) to ensure the reference architectures remain compliant > - **Test requests per second (RPS) rates:** API: 40 RPS, Web: 4 RPS, Git (Pull): 4 RPS, Git (Push): 1 RPS > - **[Latest Results](https://gitlab.com/gitlab-org/quality/performance/-/wikis/Benchmarks/Latest/2k)** | Service | Nodes | Configuration | GCP | AWS | Azure | |------------------------------------------|--------|-------------------------|-----------------|--------------|----------| | Load balancer3 | 1 | 2 vCPU, 1.8 GB memory | `n1-highcpu-2` | `c5.large` | `F2s v2` | | PostgreSQL1 | 1 | 2 vCPU, 7.5 GB memory | `n1-standard-2` | `m5.large` | `D2s v3` | | Redis2 | 1 | 1 vCPU, 3.75 GB memory | `n1-standard-1` | `m5.large` | `D2s v3` | | Gitaly | 1 | 4 vCPU, 15 GB memory | `n1-standard-4` | `m5.xlarge` | `D4s v3` | | GitLab Rails | 2 | 8 vCPU, 7.2 GB memory | `n1-highcpu-8` | `c5.2xlarge` | `F8s v2` | | Monitoring node | 1 | 2 vCPU, 1.8 GB memory | `n1-highcpu-2` | `c5.large` | `F2s v2` | | Object storage4 | n/a | n/a | n/a | n/a | n/a | | NFS server (non-Gitaly) | 1 | 4 vCPU, 3.6 GB memory | `n1-highcpu-4` | `c5.xlarge` | `F4s v2` | 1. Can be optionally run on reputable third-party external PaaS PostgreSQL solutions. [Google Cloud SQL](https://cloud.google.com/sql/docs/postgres/high-availability#normal) and [Amazon RDS](https://aws.amazon.com/rds/) are known to work, however Azure Database for PostgreSQL is **not recommended** due to [performance issues](https://gitlab.com/gitlab-org/quality/reference-architectures/-/issues/61). Consul is primarily used for PostgreSQL high availability so can be ignored when using a PostgreSQL PaaS setup. However it is also used optionally by Prometheus for Omnibus auto host discovery. 2. Can be optionally run as reputable third-party external PaaS Redis solutions. Google Memorystore and AWS Elasticache are known to work. 3. Can be optionally run as reputable third-party load balancing services (LB PaaS). AWS ELB is known to work. 4. Should be run on reputable third-party object storage (storage PaaS) for cloud implementations. Google Cloud Storage and AWS S3 are known to work. NOTE: For all PaaS solutions that involve configuring instances, it is strongly recommended to implement a minimum of three nodes in three different availability zones to align with resilient cloud architecture practices. ```plantuml @startuml 2k skinparam linetype ortho card "**External Load Balancer**" as elb #6a9be7 collections "**GitLab Rails** x3" as gitlab #32CD32 card "**Prometheus + Grafana**" as monitor #7FFFD4 card "**Gitaly**" as gitaly #FF8C00 card "**PostgreSQL**" as postgres #4EA7FF card "**Redis**" as redis #FF6347 cloud "**Object Storage**" as object_storage #white elb -[#6a9be7]-> gitlab elb -[#6a9be7]--> monitor gitlab -[#32CD32]--> gitaly gitlab -[#32CD32]--> postgres gitlab -[#32CD32]-> object_storage gitlab -[#32CD32]--> redis monitor .[#7FFFD4]u-> gitlab monitor .[#7FFFD4]-> gitaly monitor .[#7FFFD4]-> postgres monitor .[#7FFFD4,norank]--> redis monitor .[#7FFFD4,norank]u--> elb @enduml ``` ## Requirements Before starting, you should take note of the following requirements / guidance for this reference architecture. ### Supported CPUs This reference architecture was built and tested on Google Cloud Platform (GCP) using the [Intel Xeon E5 v3 (Haswell)](https://cloud.google.com/compute/docs/cpu-platforms) CPU platform. On different hardware you may find that adjustments, either lower or higher, are required for your CPU or node counts. For more information, see our [Sysbench](https://github.com/akopytov/sysbench)-based [CPU benchmarks](https://gitlab.com/gitlab-org/quality/performance/-/wikis/Reference-Architectures/GCP-CPU-Benchmarks). ### Supported infrastructure As a general guidance, GitLab should run on most infrastructure such as reputable Cloud Providers (AWS, GCP, Azure) and their services, or self managed (ESXi) that meet both the specs detailed above, as well as any requirements in this section. However, this does not constitute a guarantee for every potential permutation. Be aware of the following specific call outs: - [Azure Database for PostgreSQL](https://docs.microsoft.com/en-us/azure/postgresql/#:~:text=Azure%20Database%20for%20PostgreSQL%20is,high%20availability%2C%20and%20dynamic%20scalability.) is [not recommended](https://gitlab.com/gitlab-org/quality/reference-architectures/-/issues/61) due to known performance issues or missing features. - [Azure Blob Storage](https://docs.microsoft.com/en-us/azure/storage/blobs/) is recommended to be configured with [Premium accounts](https://docs.microsoft.com/en-us/azure/storage/blobs/storage-blob-block-blob-premium) to ensure consistent performance. ## Setup components To set up GitLab and its components to accommodate up to 2,000 users: 1. [Configure the external load balancing node](#configure-the-external-load-balancer) to handle the load balancing of the GitLab application services nodes. 1. [Configure PostgreSQL](#configure-postgresql), the database for GitLab. 1. [Configure Redis](#configure-redis). 1. [Configure Gitaly](#configure-gitaly), which provides access to the Git repositories. 1. [Configure the main GitLab Rails application](#configure-gitlab-rails) to run Puma, Workhorse, GitLab Shell, and to serve all frontend requests (which include UI, API, and Git over HTTP/SSH). 1. [Configure Prometheus](#configure-prometheus) to monitor your GitLab environment. 1. [Configure the object storage](#configure-the-object-storage) used for shared data objects. 1. [Configure Advanced Search](#configure-advanced-search) (optional) for faster, more advanced code search across your entire GitLab instance. 1. [Configure NFS](#configure-nfs-optional) (optional, and not recommended) to have shared disk storage service as an alternative to Gitaly or object storage. ## Configure the external load balancer In a multi-node GitLab configuration, you'll need a load balancer to route traffic to the application servers. The specifics on which load balancer to use or its exact configuration is beyond the scope of GitLab documentation. We assume that if you're managing multi-node systems like GitLab, you already have a load balancer of choice and that the routing methods used are distributing calls evenly between all nodes. Some load balancer examples include HAProxy (open-source), F5 Big-IP LTM, and Citrix Net Scaler. This documentation outline the ports and protocols needed for use with GitLab. This architecture has been tested and validated with [HAProxy](https://www.haproxy.org/) as the load balancer. Although other load balancers with similar feature sets could also be used, those load balancers have not been validated. The next question is how you will handle SSL in your environment. There are several different options: - [The application node terminates SSL](#application-node-terminates-ssl). - [The load balancer terminates SSL without backend SSL](#load-balancer-terminates-ssl-without-backend-ssl) and communication is not secure between the load balancer and the application node. - [The load balancer terminates SSL with backend SSL](#load-balancer-terminates-ssl-with-backend-ssl) and communication is *secure* between the load balancer and the application node. ### Application node terminates SSL Configure your load balancer to pass connections on port 443 as `TCP` instead of `HTTP(S)`. This will pass the connection unaltered to the application node's NGINX service, which has the SSL certificate and listens to port 443. For details about managing SSL certificates and configuring NGINX, see the [NGINX HTTPS documentation](https://docs.gitlab.com/omnibus/settings/nginx.html#enable-https). ### Load balancer terminates SSL without backend SSL Configure your load balancer to use the `HTTP(S)` protocol instead of `TCP`. The load balancer will be responsible for both managing SSL certificates and terminating SSL. Due to communication between the load balancer and GitLab not being secure, you'll need to complete some additional configuration. For details, see the [NGINX proxied SSL documentation](https://docs.gitlab.com/omnibus/settings/nginx.html#supporting-proxied-ssl). ### Load balancer terminates SSL with backend SSL Configure your load balancers (or single balancer, if you have only one) to use the `HTTP(S)` protocol rather than `TCP`. The load balancers will be responsible for the managing SSL certificates for end users. Traffic will be secure between the load balancers and NGINX in this scenario, and there's no need to add a configuration for proxied SSL. However, you'll need to add a configuration to GitLab to configure SSL certificates. For details about managing SSL certificates and configuring NGINX, see the [NGINX HTTPS documentation](https://docs.gitlab.com/omnibus/settings/nginx.html#enable-https). ### Readiness checks Ensure the external load balancer only routes to working services with built in monitoring endpoints. The [readiness checks](../../user/admin_area/monitoring/health_check.md) all require [additional configuration](../monitoring/ip_whitelist.md) on the nodes being checked, otherwise, the external load balancer will not be able to connect. ### Ports The basic load balancer ports you should use are described in the following table: | Port | Backend Port | Protocol | | ------- | ------------ | ------------------------ | | 80 | 80 | HTTP (*1*) | | 443 | 443 | TCP or HTTPS (*1*) (*2*) | | 22 | 22 | TCP | - (*1*): [Web terminal](../../ci/environments/index.md#web-terminals-deprecated) support requires your load balancer to correctly handle WebSocket connections. When using HTTP or HTTPS proxying, your load balancer must be configured to pass through the `Connection` and `Upgrade` hop-by-hop headers. For details, see the [web terminal](../integration/terminal.md) integration guide. - (*2*): When using the HTTPS protocol for port 443, you'll need to add an SSL certificate to the load balancers. If you need to terminate SSL at the GitLab application server, use the TCP protocol. If you're using GitLab Pages with custom domain support you will need some additional port configurations. GitLab Pages requires a separate virtual IP address. Configure DNS to point the `pages_external_url` from `/etc/gitlab/gitlab.rb` to the new virtual IP address. For more information, see the [GitLab Pages documentation](../pages/index.md). | Port | Backend Port | Protocol | | ------- | ------------- | --------- | | 80 | Varies (*1*) | HTTP | | 443 | Varies (*1*) | TCP (*2*) | - (*1*): The backend port for GitLab Pages depends on the `gitlab_pages['external_http']` and `gitlab_pages['external_https']` settings. For details, see the [GitLab Pages documentation](../pages/index.md). - (*2*): Port 443 for GitLab Pages must use the TCP protocol. Users can configure custom domains with custom SSL, which wouldn't be possible if SSL was terminated at the load balancer. #### Alternate SSH Port Some organizations have policies against opening SSH port 22. In this case, it may be helpful to configure an alternate SSH hostname that instead allows users to use SSH over port 443. An alternate SSH hostname requires a new virtual IP address compared to the previously described GitLab HTTP configuration. Configure DNS for an alternate SSH hostname, such as `altssh.gitlab.example.com`: | LB Port | Backend Port | Protocol | | ------- | ------------ | -------- | | 443 | 22 | TCP |
## Configure PostgreSQL In this section, you'll be guided through configuring an external PostgreSQL database to be used with GitLab. ### Provide your own PostgreSQL instance If you're hosting GitLab on a cloud provider, you can optionally use a managed service for PostgreSQL. A reputable provider or solution should be used for this. [Google Cloud SQL](https://cloud.google.com/sql/docs/postgres/high-availability#normal) and [Amazon RDS](https://aws.amazon.com/rds/) are known to work, however Azure Database for PostgreSQL is **not recommended** due to [performance issues](https://gitlab.com/gitlab-org/quality/reference-architectures/-/issues/61). If you use a cloud-managed service, or provide your own PostgreSQL: 1. Set up PostgreSQL according to the [database requirements document](../../install/requirements.md#database). 1. Create a `gitlab` username with a password of your choice. The `gitlab` user needs privileges to create the `gitlabhq_production` database. 1. Configure the GitLab application servers with the appropriate details. This step is covered in [Configuring the GitLab Rails application](#configure-gitlab-rails). See [Configure GitLab using an external PostgreSQL service](../postgresql/external.md) for further configuration steps. ### Standalone PostgreSQL using Omnibus GitLab 1. SSH in to the PostgreSQL server. 1. [Download and install](https://about.gitlab.com/install/) the Omnibus GitLab package of your choice. Be sure to follow _only_ installation steps 1 and 2 on the page. 1. Generate a password hash for PostgreSQL. This assumes you will use the default username of `gitlab` (recommended). The command will request a password and confirmation. Use the value that is output by this command in the next step as the value of `POSTGRESQL_PASSWORD_HASH`. ```shell sudo gitlab-ctl pg-password-md5 gitlab ``` 1. Edit `/etc/gitlab/gitlab.rb` and add the contents below, updating placeholder values appropriately. - `POSTGRESQL_PASSWORD_HASH` - The value output from the previous step - `APPLICATION_SERVER_IP_BLOCKS` - A space delimited list of IP subnets or IP addresses of the GitLab application servers that will connect to the database. Example: `%w(123.123.123.123/32 123.123.123.234/32)` ```ruby # Disable all components except PostgreSQL related ones roles(['postgres_role']) # Set the network addresses that the exporters used for monitoring will listen on node_exporter['listen_address'] = '0.0.0.0:9100' postgres_exporter['listen_address'] = '0.0.0.0:9187' postgres_exporter['dbname'] = 'gitlabhq_production' postgres_exporter['password'] = 'POSTGRESQL_PASSWORD_HASH' # Set the PostgreSQL address and port postgresql['listen_address'] = '0.0.0.0' postgresql['port'] = 5432 # Replace POSTGRESQL_PASSWORD_HASH with a generated md5 value postgresql['sql_user_password'] = 'POSTGRESQL_PASSWORD_HASH' # Replace APPLICATION_SERVER_IP_BLOCK with the CIDR address of the application node postgresql['trust_auth_cidr_addresses'] = %w(127.0.0.1/32 APPLICATION_SERVER_IP_BLOCK) # Prevent database migrations from running on upgrade automatically gitlab_rails['auto_migrate'] = false ``` 1. Copy the `/etc/gitlab/gitlab-secrets.json` file from the first Omnibus node you configured and add or replace the file of the same name on this server. If this is the first Omnibus node you are configuring then you can skip this step. 1. [Reconfigure GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure) for the changes to take effect. 1. Note the PostgreSQL node's IP address or hostname, port, and plain text password. These will be necessary when configuring the [GitLab application server](#configure-gitlab-rails) later. Advanced [configuration options](https://docs.gitlab.com/omnibus/settings/database.html) are supported and can be added if needed. ## Configure Redis In this section, you'll be guided through configuring an external Redis instance to be used with GitLab. ### Provide your own Redis instance Redis version 5.0 or higher is required, as this is what ships with Omnibus GitLab packages starting with GitLab 13.0. Older Redis versions do not support an optional count argument to SPOP which is now required for [Merge Trains](../../ci/pipelines/merge_trains.md). In addition, GitLab makes use of certain commands like `UNLINK` and `USAGE` which were introduced only in Redis 4. Managed Redis from cloud providers such as AWS ElastiCache will work. If these services support high availability, be sure it is not the Redis Cluster type. Note the Redis node's IP address or hostname, port, and password (if required). These will be necessary when configuring the [GitLab application servers](#configure-gitlab-rails) later. ### Standalone Redis using Omnibus GitLab The Omnibus GitLab package can be used to configure a standalone Redis server. The steps below are the minimum necessary to configure a Redis server with Omnibus: 1. SSH in to the Redis server. 1. [Download and install](https://about.gitlab.com/install/) the Omnibus GitLab package of your choice. Be sure to follow _only_ installation steps 1 and 2 on the page. 1. Edit `/etc/gitlab/gitlab.rb` and add the contents: ```ruby ## Enable Redis roles(["redis_master_role"]) redis['bind'] = '0.0.0.0' redis['port'] = 6379 redis['password'] = 'SECRET_PASSWORD_HERE' gitlab_rails['enable'] = false # Set the network addresses that the exporters used for monitoring will listen on node_exporter['listen_address'] = '0.0.0.0:9100' redis_exporter['listen_address'] = '0.0.0.0:9121' redis_exporter['flags'] = { 'redis.addr' => 'redis://0.0.0.0:6379', 'redis.password' => 'SECRET_PASSWORD_HERE', } ``` 1. Copy the `/etc/gitlab/gitlab-secrets.json` file from the first Omnibus node you configured and add or replace the file of the same name on this server. If this is the first Omnibus node you are configuring then you can skip this step. 1. [Reconfigure Omnibus GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure) for the changes to take effect. 1. Note the Redis node's IP address or hostname, port, and Redis password. These will be necessary when [configuring the GitLab application servers](#configure-gitlab-rails) later. Advanced [configuration options](https://docs.gitlab.com/omnibus/settings/redis.html) are supported and can be added if needed. ## Configure Gitaly [Gitaly](../gitaly/index.md) server node requirements are dependent on data size, specifically the number of projects and those projects' sizes. NOTE: The Reference Architecture specs have been designed with good headroom in mind but for Gitaly, increased specs or switching to Gitaly Cluster may be required for notably large data sets or load. Due to Gitaly having notable input and output requirements, we strongly recommend that all Gitaly nodes use solid-state drives (SSDs). These SSDs should have a throughput of at least 8,000 input/output operations per second (IOPS) for read operations and 2,000 IOPS for write operations. These IOPS values are initial recommendations, and may be adjusted to greater or lesser values depending on the scale of your environment's workload. If you're running the environment on a Cloud provider, refer to their documentation about how to configure IOPS correctly. Be sure to note the following items: - The GitLab Rails application shards repositories into [repository storage paths](../repository_storage_paths.md). - A Gitaly server can host one or more storage paths. - A GitLab server can use one or more Gitaly server nodes. - Gitaly addresses must be specified to be correctly resolvable for *all* Gitaly clients. - Gitaly servers must not be exposed to the public internet, as Gitaly's network traffic is unencrypted by default. The use of a firewall is highly recommended to restrict access to the Gitaly server. Another option is to [use TLS](#gitaly-tls-support). NOTE: The token referred to throughout the Gitaly documentation is an arbitrary password selected by the administrator. This token is unrelated to tokens created for the GitLab API or other similar web API tokens. The following procedure describes how to configure a single Gitaly server named `gitaly1.internal` with the secret token `gitalysecret`. We assume your GitLab installation has two repository storages: `default` and `storage1`. To configure the Gitaly server, on the server node you want to use for Gitaly: 1. [Download and install](https://about.gitlab.com/install/) the Omnibus GitLab package of your choice. Be sure to follow _only_ installation steps 1 and 2 on the page, and _do not_ provide the `EXTERNAL_URL` value. 1. Edit the Gitaly server node's `/etc/gitlab/gitlab.rb` file to configure storage paths, enable the network listener, and to configure the token: ```ruby # /etc/gitlab/gitlab.rb # Gitaly and GitLab use two shared secrets for authentication, one to authenticate gRPC requests # to Gitaly, and a second for authentication callbacks from GitLab-Shell to the GitLab internal API. # The following two values must be the same as their respective values # of the GitLab Rails application setup gitaly['auth_token'] = 'gitalysecret' gitlab_shell['secret_token'] = 'shellsecret' # Avoid running unnecessary services on the Gitaly server postgresql['enable'] = false redis['enable'] = false puma['enable'] = false sidekiq['enable'] = false gitlab_workhorse['enable'] = false prometheus['enable'] = false alertmanager['enable'] = false grafana['enable'] = false gitlab_exporter['enable'] = false gitlab_kas['enable'] = false nginx['enable'] = false # Prevent database migrations from running on upgrade automatically gitlab_rails['auto_migrate'] = false # Configure the gitlab-shell API callback URL. Without this, `git push` will # fail. This can be your 'front door' GitLab URL or an internal load # balancer. gitlab_rails['internal_api_url'] = 'https://gitlab.example.com' # Gitaly gitaly['enable'] = true # Make Gitaly accept connections on all network interfaces. You must use # firewalls to restrict access to this address/port. # Comment out following line if you only want to support TLS connections gitaly['listen_addr'] = "0.0.0.0:8075" gitaly['prometheus_listen_addr'] = "0.0.0.0:9236" # Set the network addresses that the exporters used for monitoring will listen on node_exporter['listen_address'] = '0.0.0.0:9100' git_data_dirs({ 'default' => { 'path' => '/var/opt/gitlab/git-data' }, 'storage1' => { 'path' => '/mnt/gitlab/git-data' }, }) ``` 1. Copy the `/etc/gitlab/gitlab-secrets.json` file from the first Omnibus node you configured and add or replace the file of the same name on this server. If this is the first Omnibus node you are configuring then you can skip this step. 1. [Reconfigure GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure) for the changes to take effect. 1. Confirm that Gitaly can perform callbacks to the internal API: ```shell sudo /opt/gitlab/embedded/bin/gitaly-hooks check /var/opt/gitlab/gitaly/config.toml ``` ### Gitaly TLS support Gitaly supports TLS encryption. To be able to communicate with a Gitaly instance that listens for secure connections you will need to use `tls://` URL scheme in the `gitaly_address` of the corresponding storage entry in the GitLab configuration. You will need to bring your own certificates as this isn't provided automatically. The certificate, or its certificate authority, must be installed on all Gitaly nodes (including the Gitaly node using the certificate) and on all client nodes that communicate with it following the procedure described in [GitLab custom certificate configuration](https://docs.gitlab.com/omnibus/settings/ssl.html#install-custom-public-certificates). NOTE: The self-signed certificate must specify the address you use to access the Gitaly server. If you are addressing the Gitaly server by a hostname, you can either use the Common Name field for this, or add it as a Subject Alternative Name. If you are addressing the Gitaly server by its IP address, you must add it as a Subject Alternative Name to the certificate. [gRPC does not support using an IP address as Common Name in a certificate](https://github.com/grpc/grpc/issues/2691). It's possible to configure Gitaly servers with both an unencrypted listening address (`listen_addr`) and an encrypted listening address (`tls_listen_addr`) at the same time. This allows you to do a gradual transition from unencrypted to encrypted traffic, if necessary. To configure Gitaly with TLS: 1. Create the `/etc/gitlab/ssl` directory and copy your key and certificate there: ```shell sudo mkdir -p /etc/gitlab/ssl sudo chmod 755 /etc/gitlab/ssl sudo cp key.pem cert.pem /etc/gitlab/ssl/ sudo chmod 644 key.pem cert.pem ``` 1. Copy the cert to `/etc/gitlab/trusted-certs` so Gitaly will trust the cert when calling into itself: ```shell sudo cp /etc/gitlab/ssl/cert.pem /etc/gitlab/trusted-certs/ ``` 1. Edit `/etc/gitlab/gitlab.rb` and add: ```ruby gitaly['tls_listen_addr'] = "0.0.0.0:9999" gitaly['certificate_path'] = "/etc/gitlab/ssl/cert.pem" gitaly['key_path'] = "/etc/gitlab/ssl/key.pem" ``` 1. Delete `gitaly['listen_addr']` to allow only encrypted connections. 1. Save the file and [reconfigure GitLab](../restart_gitlab.md#omnibus-gitlab-reconfigure). ## Configure GitLab Rails This section describes how to configure the GitLab application (Rails) component. In our architecture, we run each GitLab Rails node using the Puma webserver, and have its number of workers set to 90% of available CPUs, with four threads. For nodes running Rails with other components, the worker value should be reduced accordingly. We've determined that a worker value of 50% achieves a good balance, but this is dependent on workload. On each node perform the following: 1. If you're [using NFS](#configure-nfs-optional): 1. If necessary, install the NFS client utility packages using the following commands: ```shell # Ubuntu/Debian apt-get install nfs-common # CentOS/Red Hat yum install nfs-utils nfs-utils-lib ``` 1. Specify the necessary NFS mounts in `/etc/fstab`. The exact contents of `/etc/fstab` will depend on how you chose to configure your NFS server. See the [NFS documentation](../nfs.md) for examples and the various options. 1. Create the shared directories. These may be different depending on your NFS mount locations. ```shell mkdir -p /var/opt/gitlab/.ssh /var/opt/gitlab/gitlab-rails/uploads /var/opt/gitlab/gitlab-rails/shared /var/opt/gitlab/gitlab-ci/builds /var/opt/gitlab/git-data ``` 1. [Download and install](https://about.gitlab.com/install/) the Omnibus GitLab package of your choice. Be sure to follow _only_ installation steps 1 and 2 on the page. 1. Create or edit `/etc/gitlab/gitlab.rb` and use the following configuration. To maintain uniformity of links across nodes, the `external_url` on the application server should point to the external URL that users will use to access GitLab. This would be the URL of the [load balancer](#configure-the-external-load-balancer) which will route traffic to the GitLab application server: ```ruby external_url 'https://gitlab.example.com' # Gitaly and GitLab use two shared secrets for authentication, one to authenticate gRPC requests # to Gitaly, and a second for authentication callbacks from GitLab-Shell to the GitLab internal API. # The following two values must be the same as their respective values # of the Gitaly setup gitlab_rails['gitaly_token'] = 'gitalysecret' gitlab_shell['secret_token'] = 'shellsecret' git_data_dirs({ 'default' => { 'gitaly_address' => 'tcp://gitaly1.internal:8075' }, 'storage1' => { 'gitaly_address' => 'tcp://gitaly1.internal:8075' }, 'storage2' => { 'gitaly_address' => 'tcp://gitaly2.internal:8075' }, }) ## Disable components that will not be on the GitLab application server roles(['application_role']) gitaly['enable'] = false nginx['enable'] = true ## PostgreSQL connection details gitlab_rails['db_adapter'] = 'postgresql' gitlab_rails['db_encoding'] = 'unicode' gitlab_rails['db_host'] = '10.1.0.5' # IP/hostname of database server gitlab_rails['db_password'] = 'DB password' ## Redis connection details gitlab_rails['redis_port'] = '6379' gitlab_rails['redis_host'] = '10.1.0.6' # IP/hostname of Redis server gitlab_rails['redis_password'] = 'Redis Password' # Set the network addresses that the exporters used for monitoring will listen on node_exporter['listen_address'] = '0.0.0.0:9100' gitlab_workhorse['prometheus_listen_addr'] = '0.0.0.0:9229' sidekiq['listen_address'] = "0.0.0.0" # Set number of Sidekiq threads per queue process to the recommend number of 10 sidekiq['max_concurrency'] = 10 puma['listen'] = '0.0.0.0' # Add the monitoring node's IP address to the monitoring whitelist and allow it to # scrape the NGINX metrics. Replace placeholder `monitoring.gitlab.example.com` with # the address and/or subnets gathered from the monitoring node gitlab_rails['monitoring_whitelist'] = ['