Exadata Password policy is automatically changed back after setting it

I've got an SR with Oracle on this, but as usual they are as helpful as... :(

We have since some time an Exadata machine and last week all of a sudden the passwords for all accounts on all storage cells were expired. This was unexpected, as we had defined and implemented a password policy that included no automatic password expiry. As a side-effect, since everything is PAM enabled, all cron jobs failed (the storage cells run a few out of the box) and no alert was raised through the OEM Exadata plugin.

On closer investigation it turned out that the password policy on all accounts had been returned to the default settings. I changed them back to what we require them to be, and observed that within some 2 hours the policies were reset again. It has been satisfactorily established that no-one logged on in the mean time so this must be done by some regular process. Of course, we cannot allow ghost processes to disable part of the functionality of the storage cells, so we need to stop this automatic changing of password policies from occurring.

I've searched in all the usual places, but nothing stands out as the culprit.. Suggestions are welcome

Thanks,

Tony

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