Steps to reproduce:

1. Configure discovery action (Device uniqueness criteria: IP address)
2. Discovery action to link template and add host to group, so no adding of interfaces/hosts
3. Configure host.interfaces[#].details.dns on some discovered hots
4. Run with no problem
5. Read 7.0.17 release notes and upgrade notes
6. Upgrade from 7.0.16 to 7.0.17

Result:

• host.interfaces[#].details.dns updated from reverse DNS on all discovered hosts
• original DNS value lost without warning

Expected:
Warning about potential data loss from new feature in release notes.

Caused by ZBX-25545 just like ZBX-26792.