Troubleshooting SCIM

This section contains possible solutions for problems you might encounter.

How come I can’t add a user after I removed them?

As outlined in the Blocking access section, when you remove a user, they are removed from the group. However, their account is not deleted.

When the user is added back to the SCIM app, GitLab cannot create a new user because the user already exists.

Solution: Have a user sign in directly to GitLab, then manually link their account.

How do I diagnose why a user is unable to sign in

Ensure that the user has been added to the SCIM app.

If you receive “User is not linked to a SAML account”, then most likely the user already exists in GitLab. Have the user follow the User access and linking setup instructions.

The Identity (extern_uid) value stored by GitLab is updated by SCIM whenever id or externalId changes. Users cannot sign in unless the GitLab Identity (extern_uid) value matches the NameId sent by SAML.

This value is also used by SCIM to match users on the id, and is updated by SCIM whenever the id or externalId values change.

It is important that this SCIM id and SCIM externalId are configured to the same value as the SAML NameId. SAML responses can be traced using debugging tools, and any errors can be checked against our SAML troubleshooting docs.

How do I verify user’s SAML NameId matches the SCIM externalId

Admins can use the Admin Area to list SCIM identities for a user.

Group owners can see the list of users and the externalId stored for each user in the group SAML SSO Settings page.

A possible alternative is to use the SCIM API to manually retrieve the externalId we have stored for users, also called the external_uid or NameId.

To see how the external_uid compares to the value returned as the SAML NameId, you can have the user use a SAML Tracer.

Update or fix mismatched SCIM externalId and SAML NameId

Whether the value was changed or you need to map to a different field, ensure id, externalId, and NameId all map to the same field.

If the GitLab externalId doesn’t match the SAML NameId, it needs to be updated in order for the user to sign in. Ideally your identity provider is configured to do such an update, but in some cases it may be unable to do so, such as when looking up a user fails due to an ID change.

Be cautious if you revise the fields used by your SCIM identity provider, typically id and externalId. We use these IDs to look up users. If the identity provider does not know the current values for these fields, that provider may create duplicate users.

If the externalId for a user is not correct, and also doesn’t match the SAML NameID, you can address the problem in the following ways:

  • You can have users unlink and relink themselves, based on the “SAML authentication failed: User has already been taken” section.
  • You can unlink all users simultaneously, by removing all users from the SAML app while provisioning is turned on.
  • It may be possible to use the SCIM API to manually correct the externalId stored for users to match the SAML NameId. To look up a user, you need to know the desired value that matches the NameId as well as the current externalId.

It is important not to update these to incorrect values, since this causes users to be unable to sign in. It is also important not to assign a value to the wrong user, as this causes users to get signed into the wrong account.

I need to change my SCIM app

Individual users can follow the instructions in the “SAML authentication failed: User has already been taken” section.

Alternatively, users can be removed from the SCIM app which de-links all removed users. Sync can then be turned on for the new SCIM app to link existing users.

The SCIM app is throwing "User has already been taken","status":409 error message

Changing the SAML or SCIM configuration or provider can cause the following problems:

ProblemSolution
SAML and SCIM identity mismatch.First verify that the user’s SAML NameId matches the SCIM externalId and then update or fix the mismatched SCIM externalId and SAML NameId.
SCIM identity mismatch between GitLab and the identity provider SCIM app.You can confirm whether you’re hitting the error because of your SCIM identity mismatch between your SCIM app and GitLab.com by using SCIM API which shows up in the id key and compares it with the user externalId in the SCIM app. You can use the same SCIM API to update the SCIM id for the user on GitLab.com.

Search Rails logs for SCIM requests

GitLab.com administrators can search for SCIM requests in the api_json.log using the pubsub-rails-inf-gprd-* index in Kibana. Use the following filters based on the SCIM API:

  • json.path: /scim/v2/groups/<group-path>
  • json.params.value: <externalId>

In a relevant log entry, the json.params.value shows the values of SCIM parameters GitLab receives. These values can be used to verify if SCIM parameters configured in an identity provider’s SCIM app are communicated to GitLab as intended. For example, we can use these values as a definitive source on why an account was provisioned with a certain set of details. This information can help where an account was SCIM provisioned with details that appear to be incongruent with what might have been configured within an identity provider’s SCIM app.

Azure

How do I verify my SCIM configuration is correct?

Review the following:

  • Ensure that the SCIM value for id matches the SAML value for NameId.
  • Ensure that the SCIM value for externalId matches the SAML value for NameId.

Review the following SCIM parameters for sensible values:

  • userName
  • displayName
  • emails[type eq "work"].value

Testing Azure connection: invalid credentials

When testing the connection, you may encounter an error: You appear to have entered invalid credentials. Please confirm you are using the correct information for an administrative account. If Tenant URL and secret token are correct, check whether your group path contains characters that may be considered invalid JSON primitives (such as .). Removing such characters from the group path typically resolves the error.

(Field) can’t be blank sync error

When checking the Audit Events for the Provisioning, you can sometimes see the error Namespace can't be blank, Name can't be blank, and User can't be blank.

This is likely caused because not all required fields (such as first name and last name) are present for all users being mapped.

As a workaround, try an alternate mapping:

  1. Follow the Azure mapping instructions from above.
  2. Delete the name.formatted target attribute entry.
  3. Change the displayName source attribute to have name.formatted target attribute.

Failed to match an entry in the source and target systems Group ‘Group-Name’

Group provisioning in Azure can fail with the Failed to match an entry in the source and target systems Group 'Group-Name' error message, and the error response can include a HTML result of the GitLab URL https://gitlab.com/users/sign_in.

This error is harmless and occurs because Group provisioning was turned on but GitLab SCIM integration does not support it nor require it. To remove the error, follow the instructions in the Azure configuration guide to disable the option Synchronize Azure Active Directory Groups to AppName.