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Support Article

SAMLAuth Service displays 400 Error



SAMLAuth Service generates an error and unable to log in to the application using Single Sign-On (SSO) URL.

Error Messages

Error 400

Error in the server logs:

org.apache.coyote.http11.AbstractHttp11Processor process

INFO: Error parsing HTTP request header

Note: further occurrences of HTTP header parsing errors will be logged at DEBUG level.

java.lang.IllegalArgumentException: Request header is too large 
at org.apache.coyote.http11.InternalAprInputBuffer.fill( 
at org.apache.coyote.http11.InternalAprInputBuffer.parseHeader( 
at org.apache.coyote.http11.InternalAprInputBuffer.parseHeaders( 
at org.apache.coyote.http11.AbstractHttp11Processor.process( 
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process( 
at java.util.concurrent.ThreadPoolExecutor.runWorker( 
at java.util.concurrent.ThreadPoolExecutor$ 
at org.apache.tomcat.util.threads.TaskThread$ 

Steps to Reproduce

  1. Create an SSO authentication.
  2. Log in to the application.

Root Cause

The error occurred since the HTTP Request header was large.


As a local-change, increase the HTTP Header size from the Server end.

Published December 2, 2021

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