Failed update from 18.03

I tried to update from 18.03 to 19 and the update failed. The server is unusable. Is there anywhere I can get the ISO for 18.03 to restore the server?

I dont know about the ISO, but there is a parameter to load and install a specific version of wazo with the install script:

If you set up a virtual machine with your desired linux distribution and install wazo with this script, you can create an ISO for yourself. Just remember to configure the ethernet adapters (I think there is cloud configuration packages for that)

Thank you for the suggestion. I will try.