This section will handle the Logs of CRM and Tomcat
Step 1. The Logs! Where are they and how do we use them. We can use both the CRM logs which reside in [CRM install directory]/[CRM instance]/logs. However the less known, Tomcat logs are located in a different folder [CRM install directory]/[CRM instance]/tomcat/logs. Here you can find the catalina, localhost and localhost_access logs. There are a few others, but you will mainly look at these for your errors. When looking for errors, the start of a log line should be, "SEVERE:" or when looking at the access log, anything that is not a code 200, so basically a 401, 404, 500...any of those will be related to a tomcat issue.
Best practice is to delete the logs and let Tomcat create new ones when troubleshooting. If the logs do not want to delete -> due to Tomcat running, then you can open them and select all and clear them out and hit save. This should create nice blank logs to work with.
Here are examples of what a server error would look like
SEVERE: The web application [/crmj] created a ThreadLocal...
An access log error would look something like this
127.0.0.1 - - [24/Nov/2019:23:00:06 +0200] "GET /crmj/$service/getCallLists HTTP/1.1" 401 983
As you can see the 401 at the back tells us that the response code is 401, which means tomcat is getting an unauthorized response. This can be fixed by looking at the IIS settings for sdata, covered later in the steps.
Lets move on to Step 2