Steps to reproduce:

1. Upgrade ZabbixServer from 6.0.6 to 7.0.8

Result:

The autoregister process inserts many records in the table autoreg_host, the same host is inserted thousands of times, after two days the table hace 1600000 records. Obviously, the same host is inserted many times in the table.

When the ZabbixServer is restarted tries to register all the host inserted in the table autoreg_host, this action takes a lot of time to complete.

Expected:
Each host should be inserted just one time in the table autoreg_host.