gitlab-org--gitlab-foss/doc/security/two_factor_authentication.md

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---
type: howto
stage: Manage
group: Authentication and Authorization
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
---
# Enforce two-factor authentication **(FREE)**
Two-factor authentication (2FA) provides an additional level of security to your
users' GitLab account. When enabled, users are prompted for a code generated by an application in
addition to supplying their username and password to sign in.
Read more about [two-factor authentication (2FA)](../user/profile/account/two_factor_authentication.md)
## Enforce 2FA for all users **(FREE SELF)**
Users on GitLab can enable it without any administrator's intervention. If you
want to enforce everyone to set up 2FA, you can choose from two different ways:
- Enforce on next login.
- Suggest on next login, but allow a grace period before enforcing.
After the configured grace period has elapsed, users can sign in but
cannot leave the 2FA configuration area at `/-/profile/two_factor_auth`.
To enable 2FA for all users:
1. On the top bar, select **Main menu > Admin**.
1. On the left sidebar, select **Settings > General** (`/admin/application_settings/general`).
1. Expand the **Sign-in restrictions** section, where you can configure both.
If you want 2FA enforcement to take effect during the next sign-in attempt,
change the grace period to `0`.
### Disable 2FA enforcement through Rails console
Using the [Rails console](../administration/operations/rails_console.md), enforcing 2FA for
all user can be disabled. Connect to the Rails console and run:
```ruby
Gitlab::CurrentSettings.update!('require_two_factor_authentication': false)
```
## Enforce 2FA for all users in a group **(FREE)**
> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/24965) in GitLab 12.0, 2FA settings for a group are also applied to subgroups.
Prerequisites:
- You must have the Maintainer or Owner role for the group.
To enforce 2FA only for certain groups:
1. On the top bar, select **Main menu > Groups** and find your group.
1. On the left sidebar, select **Settings > General**.
1. Expand **Permissions and group features**.
1. Select **All users in this group must set up two-factor authentication**.
1. Select **Save changes**.
You can also specify a grace period in the **Delay 2FA enforcement** option.
If you want to enforce 2FA only for certain groups, you can enable it in the
group settings and specify a grace period as above.
The following are important notes about 2FA:
- Projects belonging to a 2FA-enabled group that
[is shared](../user/project/members/share_project_with_groups.md)
with a 2FA-disabled group will *not* require members of the 2FA-disabled group to use
2FA for the project. For example, if project *P* belongs to 2FA-enabled group *A* and
is shared with 2FA-disabled group *B*, members of group *B* can access project *P*
without 2FA. To ensure this scenario doesn't occur,
[prevent sharing of projects](../user/group/access_and_permissions.md#prevent-a-project-from-being-shared-with-groups)
for the 2FA-enabled group.
- If you add additional members to a project within a group or subgroup that has
2FA enabled, 2FA is **not** required for those individually added members.
- If there are multiple 2FA requirements (for example, group + all users, or multiple
groups) the shortest grace period is used.
- It is possible to prevent subgroups from setting up their own 2FA requirements:
1. Go to the top-level group's **Settings > General**.
1. Expand the **Permissions and group features** section.
1. Uncheck the **Allow subgroups to set up their own two-factor authentication rule** field.
This action causes all subgroups with 2FA requirements to stop requiring that from their members.
- Access tokens are not required to provide a second factor for authentication because they are API-based.
Tokens generated before 2FA is enforced remain valid.
## Disable 2FA **(FREE SELF)**
WARNING:
Disabling 2FA for users does not disable the [enforce 2FA for all users](#enforce-2fa-for-all-users)
or [enforce 2FA for all users in a group](#enforce-2fa-for-all-users-in-a-group)
settings. You must also disable any enforced 2FA settings so users aren't asked to set up 2FA again
when they next sign in to GitLab.
WARNING:
This is a permanent and irreversible action. Users must reactivate 2FA to use it again.
### For a single user
To disable 2FA for non-administrator users, we recommend using the [API endpoint](../api/users.md#disable-two-factor-authentication)
instead of the Rails console.
Using the [Rails console](../administration/operations/rails_console.md), 2FA for a single user can be disabled.
Connect to the Rails console and run:
```ruby
admin = User.find_by_username('<USERNAME>')
user_to_disable = User.find_by_username('<USERNAME>')
TwoFactor::DestroyService.new(admin, user: user_to_disable).execute
```
### For all users
There may be some special situations where you want to disable 2FA for everyone
even when forced 2FA is disabled. There is a Rake task for that:
```shell
# Omnibus installations
sudo gitlab-rake gitlab:two_factor:disable_for_all_users
# Installations from source
sudo -u git -H bundle exec rake gitlab:two_factor:disable_for_all_users RAILS_ENV=production
```
## 2FA for Git over SSH operations **(PREMIUM)**
> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/270554) in GitLab 13.7.
> - [Moved](https://gitlab.com/gitlab-org/gitlab/-/issues/299088) from GitLab Free to GitLab Premium in 13.9.
> - It's deployed behind a feature flag, disabled by default.
> - Push notification support [introduced](https://gitlab.com/gitlab-org/gitlab-shell/-/issues/506) in GitLab 15.3.
FLAG:
On self-managed GitLab, by default this feature is not available. To make it available, ask an administrator to [enable the feature flag](../administration/feature_flags.md) named `two_factor_for_cli`. On GitLab.com, this feature is not available. The feature is not ready for production use. This feature flag also affects [session duration for Git Operations when 2FA is enabled](../user/admin_area/settings/account_and_limit_settings.md#customize-session-duration-for-git-operations-when-2fa-is-enabled).
Two-factor authentication can be enforced for Git over SSH operations. However, we recommend using
[ED25519_SK](../user/ssh.md#ed25519_sk-ssh-keys) or [ECDSA_SK](../user/ssh.md#ecdsa_sk-ssh-keys) SSH keys instead.
To perform one-time password (OTP) verification, run:
```shell
ssh git@<hostname> 2fa_verify
```
Then authenticate by either:
- Entering the correct OTP.
- In GitLab 15.3 and later, responding to a device push notification if
[FortiAuthenticator is enabled](../user/profile/account/two_factor_authentication.md#enable-one-time-password-using-fortiauthenticator).
After successful authentication, you can perform Git over SSH operations for 15 minutes (default) with the associated
SSH key.
### Security limitation
2FA does not protect users with compromised *private* SSH keys.
Once an OTP is verified, anyone can run Git over SSH with that private SSH key for
the configured [session duration](../user/admin_area/settings/account_and_limit_settings.md#customize-session-duration-for-git-operations-when-2fa-is-enabled).
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