I was not been able to login to the magento2 backend even if I provided correct username and password combination. Google took me over to here. But it appears to be for older version of magento. But similar solution worked.
Open app/code/core/Mage/Core/Model/Session/Abstract.php and comment line 139-141. And the issue is solved. I haven’t yet looked at the possible undesirable implications of this change, but locally having this is not big of an issue. I recommend not using this solution in production
