I’m upgrading my zabbix  to a clean install on a new Centos8.4 machine (MariaDB).
After import old sql，restart zabbix-server ,Web page can open but can’t login,watch zabbix log
tail -f /var/log/zabbix/zabbix_server.log

9332:20181010:174337.188 [Z3005] query failed: [1050] Table 'tag_filter' already exists [create table tag_filter (
`tag_filterid` bigint unsigned not null,
`usrgrpid` bigint unsigned not null,
`groupid` bigint unsigned not null,
`tag` varchar(255) default '' not null,
`value` varchar(255) default '' not null,
primary key (tag_filterid)

Fix:
Login mysql

use zabbix;
drop table tag_filter;