Error "Request-URI Too long" Publishing Via Connection with Okta SAML

Issue

When publishing a workbook from Tableau Desktop to Tableau Server where Okta SAML authentication is enabled, the following error occurs:

Request-URI Too Long
The requested URL's length exceeds the capacity limit for this server.

Environment

Tableau Desktop 10.5
Tableau Server 10.5
Okta SAML

Resolution

Configure the SAML IdP to use a redirect URL with 255 or fewer characters.

If this error is experienced after enabling multi-factored authentication (also known as MFA or 2FA), Okta Support will need to make a change on the IdP side to add the feature flag "HANDLE_MULTIPLE_VALUES_IN_REDIRECT_URL". This flag will allow Okta to handle Tableau Desktop's redirects during multi-factor authentication.

Alternatively, disable SAML for use from Tableau Desktop.
Open a command prompt as an administrator and navigate to the Tableau Server bin directory, located by default at C:\Program Files\Tableau\Tableau Server\<version>\bin. Then run the following commands:

tabadmin stop
tabdmin set wgserver.authentication.desktop_nosaml true
tabadmin config
tabadmin start

Cause

The Okta IdP is using a session redirect link to retrieve the session cookie, and the URL is too long for the internal web connection used by Tableau Desktop. See the section on "Retrieving a session cookie by visiting a session redirect link" at Session cookie in Okta's documentation. The limitation is similar to the one documented for Internet Explorer.