Restart machine, getting CRJAZ1394E when trying login to JTS, LDAP used

HI

This is another phenomenon related to JTS+LDAP user authentication.
The tool is normally working fine till we restarted the machine.

We restarted machine and then start Rhapsody DM which is running on Tomcat with LDAP authentication applied.
Users with "JazzUsers" group assigned got below error when trying to login JTS or other Jazz Application page.
>>HTTP Status 403 - CRJAZ1394E The "xxxxx" user ID cannot connect to
>>the repository because it is not assigned to a repository group that
>>has permissions to access the repository.

We checked the user profile in JTS and we could see "JazzUsers" is checked on so we don't understand why the tool still report above error.

Then we tried to restart Tomcat, and found the issue just gone without changing any configuration files.
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Do you ever see the similar phenomenon?
What could be the possible cause here?
What could be the differences for restarting machine other than restarting Tomcat server?
When the console mentioned the server is started, does it mean the LDAP group mapping info has been completed read into memory?

Regards