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WAF error in some labs/classrooms but not all

WAF error in some labs/classrooms but not all

by Tim Alderson -
Number of replies: 4

I am getting reports of various faculty getting a WAF error when trying to access WW via D2L and LTI.

This is not happening in all labs/classrooms, and all seems to work fine from personal machines. My main concern is with the student labs.

We have used D2L+LTI for several years without issue. We did upgrade to 2.16 this summer. 

Issue occurs with various browsers, and only with LTI (instructor can login via WW login page fine).

No response yet from our IT folks as they are swamped with term starting up. I just thought I would post in case someone else has encountered this issue and has a fix or suggestion.  

Thanks in advance for any suggestions.


In reply to Tim Alderson

Re: WAF error in some labs/classrooms but not all

by Glenn Rice -

What are the cookie settings for WeBWorK on your server? That is usually the problem with LTI authentication.

In reply to Glenn Rice

Re: WAF error in some labs/classrooms but not all

by Tim Alderson -

Thank you for the suggestion. I will check out these settings when on site on Monday.

In reply to Tim Alderson

Re: WAF error in some labs/classrooms but not all

by Tim Alderson -

Problem resolved!

Turns out the issue was caused by one of AV, IPS or WAF on the subnet involved. Later this week (hopefully tomorrow) we will try adding back the services one at a time to see which was causing the problem.  

For reference, here is a screenshot of the error message

WAF error message