Invalid Request error on GUI login - suspecting MnT Restriction issue

[Breen]

Hello! I've been having some login issues when logging into the ISE GUI. After logging in, I get the message: 

"Oops. Something went wrong

Invalid request.

Request not processed - Bad input.
Please notify your administrator. If you are the administrator check your log file.

You may proceed to Login page."

I have previously cleared the cookies/cache of my browser to fix this, but that seems to have stopped working/been a coincidence. 

I suspect that the issue comes from enabling MnT Access Restriction on our pre-production deployment, as that was a recent change.

No issues with the CLI, and no issues spotted with "show application status ise".

Would anyone have any further insight or a resolution to this please?

[Rob Ingram]

@Breen what version of ISE are you running? Have you checked https://bst.cisco.com/bugsearch/bug/CSCvq29336

[Breen]

Hi, unfortunately I can't be specific regarding versions, but I don't see any issues with our Live Logs like the ones you've linked to - this seems isolated to logging into the GUI.

[Rob Ingram]

@Breen do you mean you enabled restricted MnT access from specific IP addresses? If you've locked yourself out, ISE provides a 'safe mode' startup option that can bypass IP access restrictions, try that. If that fails, log a call with TAC.

[Aref Alsouqi]

As @Rob Ingram mentioned, you can remove the IP restrictions by starting ISE with "safe" keyword and then login into the environment and remove those IP addresses. However, applying restrictions to MnT shouldn't affect your accesses to the PAN or to the admin portal, but you can give it a try and see if it helps.

Configure IP Access Restriction in ISE - Cisco