Authentication

Semaphore has three ways of establishing who somebody is. They are independent and can all be enabled at once, so the sign-in screen may offer a password form, a directory login, and one button per identity provider.

Method	Who verifies the password	Use it when
Local accounts	Semaphore, against its own database	You have no directory, or you need a break-glass administrator.
LDAP and Active Directory	Your directory server	People already exist in LDAP or AD and you want one set of credentials.
OpenID Connect	Your identity provider	You have single sign-on: Keycloak, Okta, Entra ID, Google, GitHub, and others.

Authentication only answers who the user is. What they are allowed to do is decided separately, by their server role and by their role in each project — see Teams.

How a user record comes to exist

Every person who signs in has a row in the Semaphore database, whichever method they used. A local account is created by an administrator or by semaphore user add. An LDAP or OIDC account is created on first successful sign-in, and Semaphore stores an external identity next to it: the provider ID plus the user ID that provider returned.

That external identity is what later logins match on, which means renaming somebody in the directory does not create a second account. What does need care is the first login of an existing user, where no external identity exists yet. The external_auth_email_matching option decides what happens then:

Value	Behaviour
auto (default)	Link by e-mail, but only for external users that have no identity yet. This adopts accounts created before 2.20 once, and nothing else.
always	Link by e-mail for any external user. Use it when one person signs in through several providers.
never	Never link by e-mail; identities are matched strictly by provider ID.

Local password accounts are never matched by e-mail, in any mode. An OIDC provider that lets a user choose their own e-mail address could otherwise be used to take over an administrator's account.

warning

The provider ID — the key in oidc_providers or ldap_providers — is part of every stored identity. Renaming it orphans the identities that reference it, and those users get new, empty accounts on their next sign-in. Choose it once.

Combining methods

A realistic setup enables single sign-on for people and keeps one local administrator for the day the identity provider is unreachable:

1. Configure the provider and confirm that a real user can sign in through it.
2. Give that user the roles they need.
3. Keep one local administrator account with a strong password and TOTP enabled.
4. Set password_login_disable to stop everyone else from using passwords.

Do those in order. Setting password_login_disable before step 1 works exactly as advertised and locks you out of your own server.

In this section

Page	What it covers
Local accounts	Passwords, TOTP, e-mail one-time codes, session lifetime, and disabling password login.
LDAP and Active Directory	Binding to a directory, search filters, attribute mappings, and TLS.
OpenID Connect	Provider configuration, claim expressions, IdP-initiated login, and twelve worked provider examples.

Where to start

A new installation already has the local administrator created during setup, so start with Local accounts to secure it, then add OpenID Connect or LDAP for everyone else.