Hi @Henry_Cen,
Good news! This should be fixed by this PR:
Note that the 1.0rc1 release did not support upgrading from a previously existing Kong cluster (as noted in the release notes):
Kong 1.0 (rc1) available for download
This release candidate does not support an upgrade from an existing Kong cluster (yet). Kong 1.0.0rc1 should be installed on a fresh cluster.
Another good news: 1.0rc2 (coming out later this day) will support upgrades from 0.14 clusters 
Best,