CDS can use several authentication backends:
All backends can be enabled at the same time, ie. a user can authenticate both with GitHub, GitLab, Ldap or with local authentication at the same time.
Edit the toml configuration file:
[api.auth.local]
enabled = true
signupDisabled = true
signupAllowedDomains
[api.auth.local]
enabled = true
# Allow signup from selected domains only - comma separated. Example: your-domain.com,another-domain.com
# signupAllowedDomains = ""
signupDisabled = false