Debian 7

What database are you using?
Do you use automatic population of host inventory?

Please attach an output of this sql statement:

select type, length(type) from host_inventory where type like '%GS-4012S%';

Seems problem with trailing or leading spaces. These can be received by automatic population of host inventory.

DB type: mysql; Use autodiscovery;

mysql> select type, length(type) from host_inventory where type like '%GS-4012F%';
+----------+--------------+
| type     | length(type) |
+----------+--------------+
| GS-4012F |            8 |
+----------+--------------+
1 row in set (0.00 sec)

Sorry for a delay.

The issue still reproducible with such data (without spaces)? I can reproduce it on my environment only with inventory data with trailing spaces.

Yes. Still reproduce. I have hosts > 1000, may be inventory work only with first 1000 hosts?

I'm analyze SQL queries and saw

SELECT h.hostid,h.name,h.status FROM hosts h WHERE h.flags IN (0,4) AND h.status IN (0,1) AND h.hostid IN ( SELECT hin.hostid FROM host_inventory hin) LIMIT 1001 OFFSET 0

It is a duplicate of ZBX-4633.