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Why am I asked for a password to enter the admin section?
This is by design in Jira and Confluence and is called Secure Admin sessions. If you would like users to be able to enter the admin section without entering their passwords, Atlassian has a way of disabling secure administrator sessions this (WebSudo).
Guide for disabling in Jira:
https://confluence.atlassian.com/adminjiraserver073/configuring-secure-administrator-sessions-861254024.html
In Confluence, please navigate to the address <your_confluence_url>/admin/viewsecurityconfig.action and turn off the value “Secure administrator sessions”.
In version 5.1.0 of Kantega SSO re-login via a SAML or OIDC based Identity Provider has been added to perform websudo (see below image).
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User Directories
How are Kerberos users mapped to accounts in User Directories?
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