## WeBWorK Problems

### LTI authentication failed through Canvas Part 2

by tim Payer -
Number of replies: 2
Greetings,

Last week I had a complete successful test of my Webwork to Canvas LTI connection in two separated courses: humboldt-math1059am and humboldt-stat109.

Today while checking another problems set, the LTI is not working.

Specifically the error message reported is:

Unable to update LMS grade. Error: Can't connect to canvas.humboldt.edu:443 at /opt/webwork/webwork2/lib/WeBWorK/Authen/LTIAdvanced/SubmitGrade.pm line 283.

Would this indicate a problem on the Webwork side or Canvas side?

Any help is most appreciated.

Tim

### Re: LTI authentication failed through Canvas Part 2

by Danny Glin -
As you can see by the message, the issue is with the grade passback. If the message is correct, it means that the WeBWorK server couldn't establish a https connection to the Canvas server, which could be for a number of reasons: the Canvas server was temporarily unavailable, there was a network issue between the two servers, or something was blocking the connection from WeBWorK to Canvas.

If this worked previously, then it's possible that this is intermittent. It's also possible that something changed such as a firewall blocking the traffic. Are you aware of any changes in Canvas?

Of course this is all predicated on the error message being an accurate description of what went wrong.