Problem with Traffic for all vlan's

I install librenms on the server and that’s network NIC set ip : .
in other side , in switch cisco 2960 one port that plug to server is Trunk because I need passed two vlan with this range ip : —> vlan 20 ( for Servers ) —> vlan 10 ( for switches )
in vlan 20 i have Internet . when port’s switch in Mode Access and vlan 20 . Other servers and client have ping librenms server ( ) but when port’s switch in Mode Trunk will be disconnected ping’s all devices.
who to fix this problem ?
Should I install dot1q protocol for linux centos ?