I installed Tomcat and Tomcat Manager on a remote server as per the instructions on this post.
After adding it I successfully accessed the manager on http://IP_ADDRESS:8080/manager/html
Then I used the war file upload option to try to deploy the war file on it but it gives the following exception.
FAIL - Deploy Upload Failed, Exception: Cannot find operation isServiced
Just looked this up. Broken in Tomcat versions M19 and 8.5.13. Fixed in upcoming versions M20 and in 8.5.14. http://bz.apache.org/bugzilla/show_bug.cgi?id=60949. So you can roll back to M18 or 8.5.12 for now.
Sachi, I had the same issue, I was working with Tomcat 9 M19 and just went back to Tomcat 9 M18 and everything worked well again.
I was using Netbeans to develop my code when I landed with the same error. I was using Tomcat 9.0.0.M19. I followed the suggestion provided by Dan and Jon above and changed my server path in Netbeans to point to the previous version of Tomcat i.e. 9.0.0.M18 and things started working.
You can download the previous version from http://archive.apache.org/dist/tomcat/tomcat-9/v9.0.0.M18/bin/
For MAC I downloaded http://archive.apache.org/dist/tomcat/tomcat-9/v9.0.0.M18/bin/apache-tomcat-9.0.0.M18.tar.gz
This should work.