--- stage: Systems group: Distribution info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/product/ux/technical-writing/#assignments --- # Tutorial: Install and secure a single node GitLab instance **(FREE SELF)** In this tutorial you will learn how to install and securely configure a single node GitLab instance that can accommodate up to [1,000 users](../../administration/reference_architectures/1k_users.md). To install a single node GitLab instance and configure it to be secure: 1. [Secure the server](#secure-the-server) 1. [Install GitLab](#install-gitlab) 1. [Configure GitLab](#configure-gitlab) 1. [Next steps](#next-steps) ## Before you begin - A domain name, and a correct [setup of DNS](https://docs.gitlab.com/omnibus/settings/dns.html). - A Debian-based server with the following minimum specs: - 8 vCPU - 7.2 GB memory - Enough hard drive space for all your repositories. Read more about the [storage requirements](../../install/requirements.md). ## Secure the server Before installing GitLab, start by configuring your server to be a bit more secure. ### Configure the firewall You need to open ports 22 (SSH), 80 (HTTP), and 443 (HTTPS). You can do this by either using your cloud provider's console, or at the server level. In this example, you'll configure the firewall using [`ufw`](https://wiki.ubuntu.com/UncomplicatedFirewall). You'll deny access to all ports, allow ports 80 and 443, and finally, rate limit access to port 22. `ufw` can deny connections from an IP address that has attempted to initiate 6 or more connections in the last 30 seconds. 1. Install `ufw`: ```shell sudo apt install ufw ``` 1. Enable and start the `ufw` service: ```shell sudo systemctl enable --now ufw ``` 1. Deny all other ports except the required ones: ```shell sudo ufw default deny sudo ufw allow http sudo ufw allow https sudo ufw limit ssh/tcp ``` 1. Finally, activate the settings. The following needs to run only once, the first time you install the package. Answer yes (`y`) when prompted: ```shell sudo ufw enable ``` 1. Verify that the rules are present: ```shell $ sudo ufw status Status: active To Action From -- ------ ---- 80/tcp ALLOW Anywhere 443 ALLOW Anywhere 22/tcp LIMIT Anywhere 80/tcp (v6) ALLOW Anywhere (v6) 443 (v6) ALLOW Anywhere (v6) 22/tcp (v6) LIMIT Anywhere (v6) ``` ### Configure the SSH server To further secure your server, configure SSH to accept public key authentication, and disable some features that are potential security risks. 1. Open `/etc/ssh/sshd_config` with your editor and make sure the following are present: ```plaintext PubkeyAuthentication yes PasswordAuthentication yes UsePAM yes UseDNS no AllowTcpForwarding no X11Forwarding no PrintMotd no PermitTunnel no # Allow client to pass locale environment variables AcceptEnv LANG LC_* # override default of no subsystems Subsystem sftp /usr/lib/openssh/sftp-server # Protocol adjustments, these would be needed/recommended in a FIPS or # FedRAMP deployment, and use only strong and proven algorithm choices Protocol 2 Ciphers aes128-ctr,aes192-ctr,aes256-ctr HostKeyAlgorithms ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521 KexAlgorithms ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521 Macs hmac-sha2-256,hmac-sha2-512 ``` 1. Save the file and restart the SSH server: ```shell sudo systemctl restart ssh ``` If restarting SSH fails, check that you don't have any duplicate entries in `/etc/ssh/sshd_config`. ### Ensure only authorized users are using SSH for Git access Next, ensure that users cannot pull down projects using SSH unless they have a valid GitLab account that can perform Git operations over SSH. To ensure that only authorized users are using SSH for Git access: 1. Add the following to your `/etc/ssh/sshd_config` file: ```plaintext # Ensure only authorized users are using Git AcceptEnv GIT_PROTOCOL ``` 1. Save the file and restart the SSH server: ```shell sudo systemctl restart ssh ``` ### Make some kernel adjustments Kernel adjustments do not completely eliminate the threat of an attack, but they add an extra layer of security. 1. Open a new file with your editor under `/etc/sysctl.d`, for example `/etc/sysctl.d/99-gitlab-hardening.conf`, and add the following. NOTE: The naming and source directory decide the order of processing, which is important because the last parameter processed might override earlier ones. ```plaintext ## ## The following help mitigate out of bounds, null pointer dereference, heap and ## buffer overflow bugs, use-after-free etc from being exploited. It does not 100% ## fix the issues, but seriously hampers exploitation. ## # Default is 65536, 4096 helps mitigate memory issues used in exploitation vm.mmap_min_addr=4096 # Default is 0, randomize virtual address space in memory, makes vuln exploitation # harder kernel.randomize_va_space=2 # Restrict kernel pointer access (for example, cat /proc/kallsyms) for exploit assistance kernel.kptr_restrict=2 # Restrict verbose kernel errors in dmesg kernel.dmesg_restrict=1 # Restrict eBPF kernel.unprivileged_bpf_disabled=1 net.core.bpf_jit_harden=2 # Prevent common use-after-free exploits vm.unprivileged_userfaultfd=0 ## Networking tweaks ## ## ## Prevent common attacks at the IP stack layer ## # Prevent SYNFLOOD denial of service attacks net.ipv4.tcp_syncookies=1 # Prevent time wait assassination attacks net.ipv4.tcp_rfc1337=1 # IP spoofing/source routing protection net.ipv4.conf.all.rp_filter=1 net.ipv4.conf.default.rp_filter=1 net.ipv6.conf.all.accept_ra=0 net.ipv6.conf.default.accept_ra=0 net.ipv4.conf.all.accept_source_route=0 net.ipv4.conf.default.accept_source_route=0 net.ipv6.conf.all.accept_source_route=0 net.ipv6.conf.default.accept_source_route=0 # IP redirection protection net.ipv4.conf.all.accept_redirects=0 net.ipv4.conf.default.accept_redirects=0 net.ipv4.conf.all.secure_redirects=0 net.ipv4.conf.default.secure_redirects=0 net.ipv6.conf.all.accept_redirects=0 net.ipv6.conf.default.accept_redirects=0 net.ipv4.conf.all.send_redirects=0 net.ipv4.conf.default.send_redirects=0 ``` 1. On the next server reboot, the values will be loaded automatically. To load them immediately: ```shell sudo sysctl --system ``` Great work, you've completed the steps to secure your server! Now you're ready to install GitLab. ## Install GitLab Now that your server is set up, install GitLab: 1. Install and configure the necessary dependencies: ```shell sudo apt update sudo apt install -y curl openssh-server ca-certificates perl locales ``` 1. Configure the system language: 1. Edit `/etc/locale.gen` and make sure `en_US.UTF-8` is uncommented. 1. Regenerate the languages: ```shell sudo locale-gen ``` 1. Add the GitLab package repository and install the package: ```shell curl "https://packages.gitlab.com/install/repositories/gitlab/gitlab-ee/script.deb.sh" | sudo bash ``` To see the contents of the script, visit . 1. Install the GitLab package. Provide a strong password with `GITLAB_ROOT_PASSWORD` and replace the `EXTERNAL_URL` with your own. Don't forget to include `https` in the URL, so that a Let's Encrypt certificate is issued. ```shell sudo GITLAB_ROOT_PASSWORD="strong password" EXTERNAL_URL="https://gitlab.example.com" apt install gitlab-ee ``` To learn more about the Let's Encrypt certificate or even use your own, read how to [configure GitLab with TLS](https://docs.gitlab.com/omnibus/settings/ssl/). If the password you set wasn't picked up, read more about [resetting the root account password](../../security/reset_user_password.md). 1. After a few minutes, GitLab is installed. Sign in using the URL you set up in `EXTERNAL_URL`. Use `root` as the username and the password you set up in `GITLAB_ROOT_PASSWORD`. Now it's time to configure GitLab! ## Configure GitLab GitLab comes with some sane default configuration options. In this section, we will change them to add more functionality, and make GitLab more secure. For some of the options you'll use the Admin Area UI, and for some of them you'll edit `/etc/gitlab/gitlab.rb`, the GitLab configuration file. ### Configure NGINX NGINX is used to serve up the web interface used to access the GitLab instance. For more information about configuring NGINX to be more secure, read about [hardening NGINX](../../security/hardening_configuration_recommendations.md#nginx). ### Configure emails Next, you'll set up and configure an email service. Emails are important for verifying new sign ups, resetting passwords, and notifying you of GitLab activity. #### Configure SMTP In this tutorial, you'll set up an [SMTP](https://docs.gitlab.com/omnibus/settings/smtp.html) server and use the [Mailgun](https://mailgun.com) SMTP provider. First, start by creating an encrypted file that will contain the login credentials, and then configure SMTP for the Linux package: 1. Create a YAML file (for example `smtp.yaml`) that contains the credentials for the SMTP server. Your SMTP password must not contain any string delimiters used in Ruby or YAML (for example, `'`) to avoid unexpected behavior during the processing of configuration settings. ```shell user_name: '' password: '' ``` 1. Encrypt the file: ```shell cat smtp.yaml | sudo gitlab-rake gitlab:smtp:secret:write ``` By default, the encrypted file is stored under `/var/opt/gitlab/gitlab-rails/shared/encrypted_configuration/smtp.yaml.enc`. 1. Remove the YAML file: ```shell rm -f smtp.yaml ``` 1. Edit `/etc/gitlab/gitlab.rb` and set up the rest of the SMTP settings. Make sure `gitlab_rails['smtp_user_name']` and `gitlab_rails['smtp_password']` are **not** present, as we've already set them up as encrypted. ```ruby gitlab_rails['smtp_enable'] = true gitlab_rails['smtp_address'] = "smtp.mailgun.org" # or smtp.eu.mailgun.org gitlab_rails['smtp_port'] = 587 gitlab_rails['smtp_authentication'] = "plain" gitlab_rails['smtp_enable_starttls_auto'] = true gitlab_rails['smtp_domain'] = "" ``` 1. Save the file and reconfigure GitLab: ```shell sudo gitlab-ctl reconfigure ``` You should now be able to send emails. To test that the configuration worked: 1. Enter the Rails console: ```shell sudo gitlab-rails console ``` 1. Run the following command at the console prompt to make GitLab send a test email: ```irb Notify.test_email('', 'Message Subject', 'Message Body').deliver_now ``` If you're unable to send emails, see the [SMTP troubleshooting section](https://docs.gitlab.com/omnibus/settings/smtp.html#troubleshooting). #### Enable the email verification Account email verification provides an additional layer of GitLab account security. When some conditions are met, for example, if there are three or more failed sign-in attempts in 24 hours, an account is locked. This feature is behind a feature flag. To enable it: 1. Enter the Rails console: ```shell sudo gitlab-rails console ``` 1. Enable the feature flag: ```ruby Feature.enable(:require_email_verification) ``` 1. Check if it's enabled (should return `true`): ```ruby Feature.enabled?(:require_email_verification) ``` For more information, read about [account email verification](../../security/email_verification.md). #### Sign outgoing email with S/MIME Notification emails sent by GitLab can be signed with [S/MIME](https://en.wikipedia.org/wiki/S/MIME) for improved security. A single pair of key and certificate files must be provided: - Both files must be PEM-encoded. - The key file must be unencrypted so that GitLab can read it without user intervention. - Only RSA keys are supported. - Optional. You can provide a bundle of Certificate Authority (CA) certs (PEM-encoded) to include on each signature. This is typically an intermediate CA. 1. Buy your certificate from a CA. 1. Edit `/etc/gitlab/gitlab.rb` and adapt the file paths: ```ruby gitlab_rails['gitlab_email_smime_enabled'] = true gitlab_rails['gitlab_email_smime_key_file'] = '/etc/gitlab/ssl/gitlab_smime.key' gitlab_rails['gitlab_email_smime_cert_file'] = '/etc/gitlab/ssl/gitlab_smime.crt' ``` 1. Save the file and reconfigure GitLab: ```shell sudo gitlab-ctl reconfigure ``` For more information, read about [signing outgoing email with S/MIME](../../administration/smime_signing_email.md). ## Next steps In this tutorial, you learned how to set up your server to be more secure, how to install GitLab, and how to configure GitLab to meet some security standards. Some [other steps](../../security/hardening_application_recommendations.md) you can take to secure GitLab include: - Disabling sign ups. By default, a new GitLab instance has sign up enabled by default. If you don't plan to make your GitLab instance public, you should to disable sign ups. - Allowing or denying sign ups using specific email domains. - Setting a minimum password length limit for new users. - Enforcing two-factor authentication for all users. There are many other things you can configure apart from hardening your GitLab instance, like configuring your own runners to leverage the CI/CD features that GitLab has to offer, or properly backing up your instance. You can read more about the [steps to take after the installation](../../install/next_steps.md).