ITSI "suite_redirect" page fails to load with shows "oops" for non admin users

[yannK]

ITSI menus send the users to "suite_redirect" page, that also fails to load with shows "oops" for non admin users Usually after an ITSI Upgrade (observed on 4.9 and later), on a Search-Head cluster.

[JLange]

Adding this because we ran into a similar problem (not the same upgrade version), but were able to resolve the issue. 

KVStore wasn't liking our certificates so we stopped splunk, removed the server.pem file and the $SPLUNK_HOME/var/lib/splunk/kvstore/mongo/mongod.lock, and started Splunk. KVStore didn't like our cert and it fixed our issue. Hopefully it helps anyone else stumbling across this thread. 

[yannK · Accepted solution]

see known bug ITSI-20605

Check the roles: are all the users impacted or are only non-admin roles impacted?
Check the web_service.log in index=_internal, do you see errors like that or different views or management views.

An unknown view name "homeview" is referenced in the navigation definition for "itsi".

Check the app metadata permissions for those views.
Example: in ../etc/apps/itsi/metadata/local.meta, look for the view "homeview"
Check which roles have read and write permissions, If only the admin can, there it's the root cause.
Compare to the default permissions in ../etc/apps/itsi/metadata/default.meta

A corrupted permissions stanza will look like that, you see no roles in the brackets :

access = delete : [ ], read : [ ], write : [ ]

Resolution

Clean the .../etc/apps/itsi/metadata/local.meta
Removed all stanzas impacted, as they were conflicting with the definition is default.meta
If the instance is a Search-head cluster, you will have to fix is on all Search Head, and restart.