Work bench has been giving this error for a week now, I see many others are experiencing the same issue. Looking for a update or any new information. UNKNOWN ERROR: read error on connection to ec2-34-194-152-137.compute-1.amazonaws.com:6379
I got the same trouble, I found fake solution about revoking your name on connected Apps on stackexchange, but it didn't work for me. I'm desperately looking for a solution but I keep finding posts mentioning the same problem or posts about how Workbench isn't supported by SF officialy which I already know but it doesn't help...
AN ACTUAL SOLUTION is : Use the Heroku App instead : https://foxworkbench.herokuapp.com/